ProMelt Snow melting Mats Specifications & Installations Ideas

ProMelt Electric Snow melting Mats

By SunTouch® A division of Watts Water Technologies, Inc.

tired of shoveling your snow out to work? Can’t drive your car to work? Use SunTouch, the snow melting system.

SunTouch ProMelt products are a simple way to eliminate snow and ice from surfaces. This instruction manual is provided as a guide to installing ProMelt Mat and ProMelt Cable, including design considerations, mat and cable installation, control installation, precautions, and surfacing guidelines.

Specifications for ProMelt Mat:

Sizes: Widths 2, 3 feet. Lengths 5 up to 56 feet

Voltages: 120, 208, 240, 277 VAC, 1-phase

Watts: 50 W/sq. ft (170 Btu/h/sq. ft) and 38 W/sq. ft (130 Btu/h/sq. ft)

Maximum heater current: 24 amps

Maximum circuit load: 50 amps

GFCI Class B (ground fault equipment protection) required for each circuit

Listing: ETL Listed for U.S. and Canada under UL 515, IEEE 515.1, and CAN/CSA C22.2 No. 130-03

Listing file number: 3151992

Application: outdoor use only, embedded in concrete, asphalt, sand (see Step 1.1)

Minimum bend radius: 1 inch

Maximum exposure temperature (continuous and storage): 221°F (105°C)

Maximum exposure temperature (short-term for asphalt covering): 285°F (140°C)

Minimum installation temperature: 40°F (4.5°C)

Installation must be performed by qualified personnel, in accordance with local codes, ANSI/NFPA 70 (NEC Article 426) and Section 62 of the CEC Part I.

Specifications for ProMelt Cable:

ProMelt Cable is a complete heating cable consisting of a series resistance heating cable and a single power lead for easy single-point connection. The heating cable length cannot be cut to fit.

Voltages: 120, 208, 240, 277 VAC, 1-phase

Watts: 50 W/sq. ft (170 Btu/h/sq. ft), spaced at 3 inches on-center

38 W/sq. ft (130 Btu/h/sqft), spaced at 4 inches on-center

(Cable is designed to operate at approximately 12.5 W/linear foot of cable at rated voltage.)

Maximum heater current: 24 amps

Maximum circuit load: 50 amps

GFCI Class B (ground fault equipment protection) required for each circuit

Listing: ETL Listed for U.S. and Canada under UL 515, IEEE 515.1, and CAN/CSA C22.2 No. 130-03

Listing file number: 3151992

Application: outdoor use only, embedded in concrete, asphalt, sand (see on this manual)

Minimum bend radius: 1 inch

Maximum exposure temperature (continuous and storage): 221°F (105°C)

Maximum exposure temperature (short-term for asphalt covering): 285°F (140°C)

Minimum installation temperature: 40°F (4.5°C)

WARNING

Installation must be performed by qualified personnel, in accordance with local codes and standards. Read these important warnings and all installation instructions prior to installation. Failure to so do can result in fire, shock, property damage, personal injury and/or death.

NEVER cut or modify the heating cable. The power lead may be cut shorter if necessary, but never removed from the heating cable.

NEVER overlap or cross over the heating cable on itself, or place heating cable closer than 2 inches from another heating cable or power lead cable.

NEVER pull any of the heating cable or factory splices into any conduit.

NEVER attempt to repair a damaged cable. Contact the factory for assistance.

ALWAYS de-energize all circuits before installing or servicing.

ALWAYS completely embed the heating cable and factory splices in concrete, sand, or asphalt.

ALWAYS avoid placing the heating cable any closer than 2 inches from other items such as underground cable or piping to keep from overheating them.

ALWAYS keep ends of the power leads dry before and during installation.

ALWAYS provide ground fault protection (GFCI) for the snow melting system. This may be at the circuit breaker or the control.

ALWAYS pay close attention to voltage and amperage requirements of the circuit breaker, control, and snow melting system.

ALWAYS install in accordance with all local codes and the National Electrical Code (ANSI/ NFPA 70 especially Article 426) and Section 62 of the Canadian Electrical Code (CEC) Part I.

Some Typical ProMelt Installations Ideas

ProMat work well on stairs and Ramps

Driveway with full coverage near garage and “tire track” coverage down driveway.

ProMelt Mats and Cables can be used in combination to fit a variety of areas.

Phase 1: Designing the System

STEP 1.1

Determine general areas where you want to install ProMelt Mat/Cable. Applications include driveways, walkways, patios, permanent ramps, masonry steps and benches, shipping docks, under garage door seals and more. Anywhere outdoors in residential or commercial locations where snow or ice accumulate may be considered, as long as ProMelt is completely embedded in concrete, sand, thick mortar bed, or asphalt.

ProMelt Mat/Cable cannot be installed indoors, in industrial locations, or areas with hazardous classifications. It cannot be used for gutter or pipe freeze protection or roof snowmelt. Do not install the mat/cable on or under non-masonry stairs or decks such as wooden or composite construction.

If installing ProMelt under brick pavers, we recommend installing cables under the entire area. This is because the non heated area will receive melt water that may re-freeze under the pavers causing the pavers to heave in the non-heated area.

If you have an application you are unsure of, please call the factory for advice.

STEP 1.2

Make a drawing and measure the area where you want snow melting to occur. Eliminate those areas where ProMelt cannot be installed, keeping in mind the following obstructions and allowances:

• Mat/Cable cannot be laid within 6 inches of the edges of slabs. In asphalt, this is increased to 12 inches from the edge where no curb is provided.

• Avoid crossing expansion joints in a slab, unless proper technique and protection steps are followed (see Step 3.14).

• Avoid placing the heating cable any closer than 2 inches from other items such as underground cable or piping to keep from overheating them.

• Allow at least 2 inches between adjacent cables, but not more than 4 inches, between adjacent cables or sections of a mat where the mat mesh is cut and turned to fill the area.

• Mat/Cable must be laid such that the surface will not have other obstructions placed on top, capturing heat or allowing potential damage from mounting brackets, bolts, or similar (pedestals, support columns, walls, light posts, or similar)

Also, consider the following precautions:

WARNING: THE HEATING CABLE CANNOT BE CUT TO LENGTH. Order the correct size mat or cable to fit the area. Modifying the heating cable is not allowed and may lead to overheating, damage, and fire hazard.

• The heating cable and factory splices of ProMelt Mat/Cable must be completely embedded in the concrete, sand, or asphalt. Never try to use up excess heating cable in surrounding soil, walls, or other unprotected applications.

• Never overlap the heating cable on itself or place heating cable closer than 2 inches from other heating cable.

• Only the power lead may exit this area. It will be pulled through conduit to protect it up to a junction box.

NEVER pull any of the heating cable or factory splices into any conduit.

See typical installations on above page.

STEP 1.3

Determine where junction box(es) may be placed to receive the ProMelt Mat/Cable power leads. This is important to ensure the mat(s) and/or cable(s) you select fill the area correctly and with the best connection locations.

It is best to locate junction boxes on a wall indoors and within the distance of the power leads on the mat/cable. ProMelt mat/cable comes standard with 20-foot long power leads, but may be custom ordered up to 50 feet long if necessary.

If a junction box must be located outdoors, it is recommended it be installed above grade and be properly Listed for rain tight use outdoors. If it must be installed at or below grade, use properly Listed watertight items and follow box manufacturer guidelines for protection and connection seals.

STEP 1.4 (ProMelt Mat Only)

Select the ProMelt Mat(s) you need. (for ProMelt Cable sizes see following page)

WATTAGE: Decide what heat output is required. Your design must consider weather conditions and how critical it is

to clear the heated area.

Mat with 50 watts per square foot heat output are sufficient to clear most moderate and heavy snowfall rates.

Mat with 38 watts per square foot heat output are sufficient to clear most light to moderate snowfall rates.

SIZE: ProMelt Mat is manufactured in a variety of sizes as shown in Table 1. If the exact size of mat is not found in the Table, select the next smaller mat size.

AMPS and VOLTS: Pay careful attention to the amps to make sure your controls, circuit breaker panel, and wiring will have the proper capacity. Design everything to handle 125 percent of heating mat load:

– 20 amp circuit for load up to 16 amps

– 30 amp circuit for load up to 24 amps

– 40 amp circuit for load up to 32 amps

– 50 amp circuit for load up to 40 amps

– 70 amp circuit for load up to 50 amps

Table 1 (mat sizes)

3′ Wide Mats – 50 Watts/Sq. Ft. 208 VAC

Mat Size	Coverage Sq. Ft	Amp Draw	Ohms
3′ x 5′	15 sq.	3.6	59 – 73
3′ x 10′	30 sq.	6.7	28 – 34
3′ x 15′	45 sq.	11.7	15 – 19
3′ x 20′	60 sq.	15.0	13 – 16
3′ x 25′	75 sq.	18.4	10 -12
3′ x 30′	90 sq.	23.4	8 – 10

3′ Wide Mats – 50 Watts/Sq. Ft. 240 VAC

Mat Size	Coverage Sq. Ft	Amp Draw	Ohms
3′ x 5′	15 sq.	3.6	68 – 83
3′ x 10′	30 sq.	7.2	32 – 39
3′ x 15′	45 sq.	10.8	21 -26
3′ x 20′	60 sq.	14.4	15 – 18
3′ x 25′	75 sq.	18.0	12 – 14
3′ x 30′	90 sq.	21.6	10 – 12
3′ x 35′	105 sq.	21.9	8 – 10

3′ Wide Mats – 50 Watts/Sq. Ft. 277 VAC

Mat Size	Coverage Sq. Ft	Amp Draw	Ohms
3′ x 10′	30 sq.	5.0	51 – 62
3′ x 15′	45 sq.	8.4	24 – 30
3′ x 20′	60 sq.	11.7	21 – 25
3′ x 25′	75 sq.	15.0	15 – 19
3′ x 30′	90 sq.	18.4	13 – 15
3′ x 35′	105 sq.	23.4	10 – 12

2′ Wide Mats – 38 Watts/Sq.Ft.. Ft. 120 VAC

Mat Size	Coverage Sq. Ft	Amp Draw	Ohms
2′ x 5′	10 sq.	3.2	42 – 53
2′ x 10′	20 sq.	6.3	20 – 25
2′ x 15′	30 sq.	9.5	13 – 17
2′ x 20′	40 sq.	12.7	7 – 10
2′ x 25′	50 sq.	15.8	6 – 8
2′ x 30′	60 sq.	19.00	4 – 6

2′ Wide Mats – 50 Watts/Sq.Ft.. Ft. 208 VAC

Mat Size	Coverage Sq. Ft	Amp Draw	Ohms
2′ x 7′	14 sq.	3.4	59 – 73
2′ x 11′	22 sq.	5.0	38 – 46
2′ x 14′	28 sq.	6.7	28 -34
2′ x 18′	36 sq.	8.4	22 – 27
2′ x 20′	40 sq.	10.0	18 – 22
2′ x 24′	48 sq.	11.7	15 – 19
2′ x 28′	56 sq.	13.4	13 – 16
2′ x 34′	68 sq.	16.7	11 – 14
2′ x 38′	76 sq.	18.4	10 – 12
2′ x 42′	84 sq.	20.0	9 – 11
2′ x 48′	96 sq.	23.4	8 -10

2′ Wide Mats – 50 Watts/Sq. Ft. 240 VAC

Mat Size	Coverage Sq. Ft	Amp Draw	Ohms
2′ x 8′	16 sq.	3.4	68 -83
2′ x 12′	24 sq.	5.0	43 – 53
2′ x 16′	32 sq.	6.7	32 – 39
2′ x 20′	40 sq.	8.4	26 – 31
2′ x 24′	48 sq.	10.0	21 – 26
2′ x 28′	56 sq.	11.7	18 – 22
2′ x 32′	64 sq.	13.4	15 – 18
2′ x 36′	72 sq.	15.0	13 – 16
2′ x 40′	80 sq.	16.7	12 – 14
2′ x 44′	88 sq.	18.4	11 – 13
2′ x 48′	96 sq.	20.0	10 – 12
2′ x 52′	104 sq.	23.4	8 -10

2′ Wide Mats – 50 Watts/Sq. Ft. 277 VAC

Mat Size	Coverage Sq. Ft	Amp Draw	Ohms
2′ x 9′	18 sq.	3.2	77 – 94
2′ x 14′	28 sq.	5.1	51 – 62
2′ x 18′	36 sq.	6.5	37 – 46
2′ x 24′	48 sq.	8.7	29 – 36
2′ x 28′	56 sq.	10.1	24 -30
2′ x 32′	64 sq.	11.6	21 -25
2′ x 36′	72 sq.	13.0	17 – 21
2′ x 40′	80 sq.	14.4	15 – 19
2′ x 44′	88 sq.	15.9	14 – 17
2′ x 48′	96 sq.	17.3	13 – 15
2′ x 52′	104 sq.	18.8	11 -14
2′ x 56′	112 sq.	20.2	10 – 12

STEP 1.4 (ProMelt Cable Only)

Select the cables you need.

WATTAGE: Decide what heat output is required. Your design must consider weather conditions and how critical it is to clear the heated area.

50 watts per square foot: sufficient to clear most moderate and heavy snowfall rates

38 watts per square foot: sufficient to clear most light to moderate snowfall rates

SIZE: Select a cable in Table 2 to fit the Heated Area measured in Step 1.2. ProMelt Cable is manufactured in a variety of sizes as shown. If the exact size of cable is not found in the Table, select the next smaller cable size.

AMPS and VOLTS: Pay careful attention to the amps to make sure your controls, circuit breaker panel, and all wiring will have the proper capacity. Design circuit protection and wiring to handle 125 percent of heating cable load:

– 20 amp circuit for load up to 16 amps

– 30 amp circuit for load up to 24 amps

– 40 amp circuit for load up to 32 amps

– 50 amp circuit for load up to 40 amps

Cables Spefication – 38 and 50 Watts/Sq. Ft. 120 VAC

3 o.c 50 W sq. ft	4 o.c 38 W sq. ft	Length (ft)	Amp Draw	Ohms
8	10	29	3.3	31 – 38
15	20	59	6.3	15 – 19
20	26	78	8.3	13 – 17
30	39	118	12.5
40	53	158	16.7	5 – 7
53	69	208	22.1	4 – 6

Cables Spefication – 38 and 50 Watts/Sq. Ft. 208 VAC

3 o.c 50 W sq. ft	4 o.c 38 W sq. ft	Length (ft)	Amp Draw	Ohms
14	19	55	3.4	60 – 74
20	26	78	4.8	36 – 46
30	39	118	7.2	30 – 38
35	46	138	8.4	23 – 29
40	53	158	9.6	18 – 23
45	59	178	10.8	14 – 19
55	72	218	13.2	13 – 17
60	79	238	14.4	11 – 15
65	85	257	15.6	10 – 13
75	98	297	18.0	9 – 12
80	105	317	19.2	8 – 11
90	118	357	21.6	7 – 9

Cables Spefication – 38 and 50 Watts/Sq. Ft. 240 VAC

3 o.c 50 W sq. ft	4 o.c 38 W sq. ft	Length (ft)	Amp Draw	Ohms
15	20	59	3.1	64 -79
25	33	98	5.2	46 – 57
30	39	118	6.3	30 – 38
40	53	158	8.3	26 – 33
45	59	178	9.4	20 – 25
55	72	218	11.5	18 – 23
60	79	238	12.5	14 – 18
65	85	257	13.5	12 – 16
75	98	297	15.6	11 – 15
80	105	317	16.7	10 – 13
90	118	357	18.8	9 – 12
105	137	417	21.9	8 – 11

Cables Spefication – 38 and 50 Watts/Sq. Ft. 277 VAC

3 o.c 50 W sq. ft	4 o.c 38 W sq. ft	Length (ft)	Amp Draw	Ohms
18	24	71	3.2	77 – 95
30	39	118	5.4	55 – 68
35	46	138	6.3	36 – 45
45	59	178	8.1	29 – 37
55	72	218	9.9	24 – 31
60	79	238	10.8	19 – 25
70	92	277	12.6	17 – 21
75	98	297	13.5	14 – 18
80	105	317	14.4	12 – 16
90	118	357	16.2	11 – 15
105	137	417	19.0	11 – 14
115	150	456	20.8	9 – 12

STEP 1.5 (ProMelt Cable only)

If the cable is to be laid on top of an existing slab, select enough Cable Strap to secure the cable to the surface.

One box contains 25 ft. of strap, enough to secure about 50 sq. ft. of cable at 4-ft parallel spacing. Cable strap is usually

spaced no more than 3 to 4 feet apart.

STEP 1.6

Select the controls and sensors for your ProMelt Mats/Cables.

Various types of controls may be used. If you need assistance in selection, see our product catalog or contact your local dealer or call the factory. Always consult your electrician and designers to ensure proper sizing, location, and site capabilities..

Refer to the Appendix for typical wire diagrams.

The following guidelines may assist to identify the best solution.

Determine Zoning:

One Zone. In many instances all the areas can be heated at the same time with one control. The control can be connected to many cables and mats with multiple circuit breakers if needed. One sensor will tell the control when to operate and when the snow is melted.

Multiple Zones. In some instances it may be preferable to have some areas heated separately from other areas. This could be the case if you want to snowmelt the sidewalks in front of a store automatically first, then melt rear entrance areas manually later. In these cases, each “zone” will require its own control and sensor. Do not try to control multiple zones with one sensor.

Determine Sensing:

Pole-mount sensing. This is the recommended method of sensing moisture and temperature in the area. The PM-2B and PM-224 are controls with the moisture sensor attached directly on top of the control, so it needs to be mounted on a conduit in a location that will receive the snowfall on top of the control. The PM-824 control has the moisture sensor attached to the end of a long length of cable, so this sensor may be mounted on a bracket or conduit away from the building to receive the snowfall, while the control is mounted on an outside wall. The PM-224 and PM-824 are low-voltage and therefore must be used with the Contactor Control. All these controls provide a reliable automatic detection of the snow and adjustable delay times to allow complete melting of the snow.

In-slab sensing. The PM-HSC5 sensor mounts directly into the slab where snow melting is placed. The location for this sensor must be chosen carefully to ensure proper operation. This is also a low-voltage sensor and must be used with the Contactor Control.

Determine Load Size to Select Controls: (Reference Appendix)

Small Load. Calculate the total “amp draw” of the mats and/or cables you have selected for the zone (see Tables 1 and 2). If the total is 30 amps or less, then you may select one of the following:

• A PM-2B control (120VAC, 208VAC, or 240VAC only), for the simplest, direct control.

• A Contactor Control, and either the PM-224 sensor control or PM-824 sensor control.

• A Contactor Control and an in-slab sensor PM-HSC5.

Large Load. If the total “amp draw” of the mats and/or cables for the zone is over 30 amps, you may select one of the following:

• A Contactor Control, and either the PM-224 sensor control or PM-824 sensor control.

• A Contactor Control and an in-slab sensor PM-HSC5.

STEP 1.7

Consult with your electrician to make sure the mats/cables, control, and design you have selected will work properly.

• The ProMelt Mat/Cable and its control must be placed on a dedicated power supply from the circuit breaker panel.

• The ProMelt Mat/Cable is a resistance heating system and should be considered as a continuous load for branch circuit sizing purposes.

• The circuit breaker must open all ungrounded conductors at the same time. A GFCI type (typically Class B, 30 mA trip) is required to directly protect the ProMelt Mat/Cable.

• Circuit breaker size and circuit wiring should be designed to 125 percent of heating mat load:

– 20 amp circuit for load up to 16 amps

– 30 amp circuit for load up to 24 amps

– 40 amp circuit for load up to 32 amps

– 50 amp circuit for load up to 40 amps

– 70 amp circuit for load up to 50 amps

• Follow NEC, CEC, and local code guidelines for branch circuit wiring, conduit, and junction box installations. Outdoor and underground junction boxes and conduit must meet rain tight or watertight requirements as required.

STEP 1.8

Insulation is not recommended underneath your slab. Improper type or use may cause cracking of the slab and possible damage to the ProMelt Mat/Cable.

ProMelt Mats and Cables can be installed in or under a variety of surfaces

(see “Phase 4-Finish Surfaces for more specific information)

Phase 2: Preparations

Before installing ProMelt, make sure to fully check out the products, and carefully plan your site. The following steps may not necessarily occur in the order shown, depending on contractor and electrician scheduling and variations in site preparation requirements. A good discussion with all parties involved will help eliminate costly errors and damages.

INSPECT MAT/CABLE, CONTROL, and SENSOR

STEP 2.1

Remove the ProMelt Mat/Cable, control, and sensor from their packages. Inspect them for any visible damage and verify everything is the correct size and type according to your plan and order. Do no attempt to install a damaged product.

STEP 2.2

Record the mat/cable information in Table 3. Give this information to the homeowner to keep in a safe place.

The mat/cable model number, serial number, voltage, and resistance range are shown on a nameplate label attached to

the power leads. Do not remove this nameplate label. The electrical inspector will need to see this.

STEP 2.3

Use a digital multi-meter to measure the resistance between the conductors of the mat power leads. Record these resistances in Table 3 under “Out of the box before installation”.

The resistance between the white lead wires should be within the resistance range on the nameplate label. If it is a little low, it may be due to low air temperatures or meter calibration. Consult the factory if you are in doubt.

The resistance between the white lead and ground lead should be “open”, usually indicated by an “OL” or whatever your meter shows when the test leads are not touching anything. If there is any change in the reading, record this information and contact the factory before installing. This could indicate damage, test lead problems, or a number of other issues. Try “pinning” the test leads to the mat/cable lead wires against a hard non-metal surface if your readings fluctuate.

STEP 2.4

Your electrician should perform an insulation resistance test on the mat. A megohmeter (e.g. Megger®) adjusted to a minimum 1000 VDC should give a measured value at least 20 meg ohm (MΩ)

WARNING: Meg ohmmeters apply high voltage and could shock or cause serious injury if improperly used. Follow meg ohmmeter instructions for safe and proper use.

The LoudMouth monitor shown at right will constantly monitor the heating wire during the entire installation process. If the wire is cut or damaged during installation, this device sounds an alarm. The LoudMouth will prevent burying a damaged wire below hardened concrete.

Please use the Mat/Cable resistance log on next page

Table 3 – Mat/Cable Resistance Log

	Mat 1	Mat 2	Mat 3
Mat / Cable Serial Number
Mat / Cable Model
Mat / Cable Voltage
Mat / Cable Resistance Range

OUT OF THE BOX BEFORE INSTALLATION

Mat / Cable white to white
Mat / Cable white to ground
Mat / Cable white to ground

AFTER MAT/CABLE IS SECURED IN PLACE

Mat / Cable white to white
Mat / Cable white to ground
Mat / Cable white to ground

AFTER COVERINGS ARE APPLIED

Mat / Cable white to white
Mat / Cable white to ground
Mat / Cable white to ground

Retain this log to retain the warranty! Do not discard!

BASE MATERIAL

STEP 2.5

Prepare the site that you want to heat with ProMelt Mat/Cable. This includes making sure all utilities and obstructions are accounted for.

STEP 2.6

Lay a smooth, well-compacted gravel base. Ensure proper slope and drainage to avoid water buildup in any heated or surrounding areas. This is especially important for brick paver applications, as melted water may re-freeze and heave surrounding sand and paver areas. Follow local building code and construction guidelines for grade thickness and type.

Make sure you account for the total grade and slab thickness as required for pedestrian and vehicular traffic use.

If the mat/cable is to be placed on an existing pavement, make sure it is inspected for any sharp objects, loose sections, or other potentially damaging issues that could cause problems later. It is very important for the cable to be completely embedded.

STEP 2.7

Concrete Application

Attach reinforcement, such as wire mesh or rebar, over the base at about 2 inches below the level of the top surface. You must use “chairs” or other appropriate objects to raise the wire mesh to the correct level. The ProMelt Mat/Cable will be attached to this reinforcement later. It is very important for the cable to be completely embedded in concrete.

Protect or remove sharp protrusions by bending them over, capping, or cutting. Sharp edges may damage the heating cable.

STEP 2.8

Asphalt Application

Apply a first course over the gravel base and compact it. The ProMelt Mat/Cable will be secured to the top of this later. Allow it to cool enough to work on before installing ProMelt Mat/Cable.

STEP 2.9

Paver or Stone Applications

Follow guidelines recommended by the paver manufacturer. If a coarse of sand is to be applied over the gravel base, the mat/cable must first be secured in place and then covered with a minimum 1-1/2 inch layer of sand to completely embed the mat.

STEP 2.10

Ceramic or Stone Tile Applications

ProMelt mats or cables can be installed in the structural slab or in a thick mortar bed above a structural slab. In either case, the base material should be prepared according to section 2.7 Concrete Application.

ELECTRICAL

STEP 2.11

Install junction boxes in the location(s) planned during the design process Phase 1 (see Step 1.3).

STEP 2.12

Install conduit and branch circuit wiring from the circuit breaker panel to the control location, and from the control to the junction boxes. Follow local code for wire size, conduit requirements, and proper installation procedure.

STEP 2.13

Install conduit from the junction box to the edge of the slab to be heated. Extend this conduit into the slab edge about 2 to 6 inches and attach a bushing to the end to prevent damaging the mat/cable power leads.

• Follow electrical code for burial depth of the conduit.

• Plan carefully if you are installing edge pavers, edge drainage systems, landscaping, or other items that affect where the conduit comes in.

STEP 2.14

If a slab sensor is to be embedded in the heated area, install conduit from the control location to the desired slab location.

Follow the sensor instructions for proper placement and connections.

STEP 2.15

Install the circuit breaker size and type as determined earlier in Step 1.7 (Designing the System). DO NOT connect the branch wiring to the breaker yet.

STEP 2.16

Label the circuit breaker in the panel which feeds this Snow Melt mat system with “Snow Melt” or similar.

Phase 3: Installation of Mat and/or Cable

The following Steps 3.1 through 3.12 cover installation basics. Steps 3.13 through 3.14 cover some specific applications and their special requirements.

BASIC INSTALLATION

STEP 3.1

Determine a time to install the mat/cable when equipment, heavy tools, and site traffic will be minimal to keep from possibly damaging the product. Be prepared to apply the surfacing courses over the mat/cable the same day so it will be protected from damage.

If installing mat/cable in the upper layer of a two-stage concrete slab or the upper layer of an asphalt application, the mat or cable should be completely ready for the second stage. There is limited

time between stages, as the slab should not be allowed to fully cure
or the asphalt to completely cool. Therefore, if using ProMelt Cable, you may want to lay it out and tie it to rewire that can be quickly lifted into place after the first is laid. This might also be preferable for a mat installation, although if mats are precut and shaped to the area, they generally can be rolled into place fairly quickly.

If a slab sensor is installed in this second layer, plan ahead so this does not cause the first layer to cure or cool too much.

Inspect the area and remove any sharp objects.

Install in temperatures at least 40°F (4.5°C).

STEP 3.2

Begin by test-fitting the mat or cable in the area to be heated. For mat, unroll it completely. Turn and flip it by cutting the tape where needed. Make sure it fits the area properly. For cable, make sure it fits the area with no excess cable.

IMPORTANT: This heating cable CANNOT be cut shorter to fit! Do not overlap or cross over heating cable on itself. Do not space heating cable closer than 2 inches. Mat/cable cannot be laid closer than 6 inches from the edges of slabs. In asphalt, this is increased • to 12 inches from the edge where no curb is provided.

• Avoid crossing expansion joints in a slab, unless proper technique and protection steps are followed (see Step 4.14 on page 16).

• Avoid placing the heating cable any closer than 2 inches from other items such as underground cable or piping to keep from overheating them.

• Allow at least 2 inches, but not more than 4 inches, between adjacent mats or sections of a mat where the mat tape is cut and turned to fill the area.

WARNING: The heating cable and factory splices of ProMelt Mat and/or Cable must be completely embedded in the concrete, sand, or asphalt. Never try to use up excess heating cable in surrounding soil, walls, or other unprotected applications.

• Do not repeatedly bend the heating cable, and never bend factory splices.

STEP 3.3

Place the power leads of the mat/cable next to the conduit entry. The electrician will pull this through the conduit later. Make sure it is positioned so that the no part of the splice connection or the heating cable will be pulled into the conduit.

STEP 3.4

Concrete Application

ProMelt Mat: Begin laying out and securing the mat about every 2 feet to the reinforcement mesh or rebar using plastic cable ties around the heating cable. Turn the cable tie ends downward, or trim them so they will not poke up through the surface layers. Do not use metal ties as they may damage the cable.

If installing on top of existing slab, secure the mat by nailing through the tape every 2 feet or so. NEVER strike the heating cable with a hammer.

ProMelt Cable: Begin securing the heating cable at the desired spacing to the reinforcement mesh or rebar using plastic cable ties. These cable ties should be applied at the ends of each run and at every 3 to 4 feet. Turn the cable tie ends downward, or trim them so they will not poke up through the surface layers. Do not use metal ties as they may damage the cable.

If installing on top of existing slab, secure CableStrap to the surface. Use nails or similar, every 6 to 10 inches. CableStrap should be placed at either end of the heated area, and additional straps should be applied every 3 to 4 feet in between to hold the cable in place during surfacing.

STEP 3.5

Asphalt Application

Begin laying and securing the mat to the first course, using nails, staples or similar into the mat tape every 2 feet or so. Make sure it is laid flat. Do not use metallic nails or staples directly over the heating cable. Be careful not to damage the heating cable.

ProMelt Cable: Secure CableStrap to the surface. Use nails or similar, every 6 to 10 inches. CableStrap should be placed at either end of the heated area, and additional straps should be applied every 3 to 4 feet in between to hold the cable in place during surfacing.

STEP 3.6

Stone or Paver Application

Begin laying out the mat and secure it onto the base with landscape fabric stakes or similar over the mat tape every 2 feet or so. Make sure it is laid flat. Do not use metallic stakes or staples directly over the heating cable. Be careful not to damage the heating cable.

ProMelt Cable: Secure plastic mounting cable ties to the gravel base, driving long nails or similar through the head of the cable tie. These cable ties should be applied at the end of each run and at every 3 to 4 feet. Do not use metallic cable ties as they may damage the cable.

Lay out the cable and secure with the cable ties.

Step 3.7

Ceramic or Stone Tile Applications

1) Dry-set or Latex-Portland Cement (thin-set) Mortar Application – For this application, the mat or cable is installed in the slab, no less than 1.5″ and no deeper than 2″ below the top surface, so follow recommendations in section 3.4 for mat or cable.

2) Cement Mortar or Thick-set Application – For this application, the cable will be installed in a minimum 1.25″ thick mortar bed above the structural slab.

Begin laying out the mat and securing to the top of the slab by nailing through the tape every 2 feet or so. Never strike the heating cable with a hammer. Minimum 1.25″ mortar bed will be installed over the cables.

ProMelt Cable: Secure CableStrap to the surface of the slab, using nails spaced every 6 to 10 inches. CableStraps should be placed at either end of the heated area for the initial layout. Additional straps should be placed every 3 to 4 feet to hold the cables in place during application of the thick-set mortar. Minimum 1.25″ mortar bed will be installed over the cables.

STEP 3.8

If you need to cut and turn the mat, or fill odd areas, you may use scissors to carefully cut the tape holding the heating cables. Heating cables should be secured at about 3 inches apart, and no less than 2 inches apart.

CAUTION: Be careful not to kink or sharply bend the heating cable. A minimum bend radius of 1 inch should be maintained.

Turn techniques for ProMelt Mats

STEP 3.9

Use a digital multi-meter to measure the resistance between the conductors of the mat/cable power leads again. Record these resistances in Table 3 under “After mat/cable is secured in place”.

STEP 3.10

Feed the power leads through the conduit into the junction box, leaving at least 6 inches of free lead length. Secure the heating cable and splice so that they will not be pulled into the conduit.

Insert a generous amount of electrical conduit sealant into the conduit end around the power leads to prevent water entry

STEP 3.11

If a slab sensor is being installed, place the sensor socket according to the instructions. Secure and seal it to the conduit installed earlier. It should be located halfway between heating cables and in an area that is recommended by the sensor manufacturer. Make sure the top of the sensor will be flush with the surface of the finish layer. Make sure it is protected with a cap or seal.

STEP 3.12

Take a photo of the mat/cable installation. This can be very helpful later for utility work, changes to the site, etc. to avoid possible damage. Keep the photos with this installation manual.

SPECIAL APPLICATIONS

STEP 3.13

Stairs: If you are installing ProMelt Mat onto stairs, carefully cut the tape holding the heating cable. If installing ProMelt Cable, skip the previous step. Secure a single run of cable to the side of a riser. Lay 3 or 4 runs of cable on the tread area as needed and continue up each stair.

Follow these guidelines:

• Lay cable no greater than 3 inches from the front edge of the finished tread. Otherwise this edge may not snow melt properly.

• Lay cable no less than 6 inches from the side edges of the finished tread.

• Account for future hand railings that could be mounted onto the tread, especially in the middle of a long tread if required. Use a marker or indicate on drawings where the railing may be installed safely later.

• Avoid pinching or sharply bending the cable. At the corner of the riser and tread, keep a minimum 1-inch radius bend, but secure it flat enough that the surface concrete or pavers will not pinch the cable.

• Do not install the mat/cable on or under non-masonry stairs such as wooden or composite construction.

ProMelt Mat on stairs

ProMelt Cable on stairs

STEP 3.14

Expansion Joints: ProMelt heating cable must never be run through an expansion joint. Doing so may cause damage to the cable with slab movement. It is recommended to lay the mat so these joints are avoided.

However, if it is necessary, a portion of the heating cable may be dropped into the grade below the expansion joint as shown. Fill around the cable with at least 1 inch thick sand. The loop of heating cable should be long enough to allow flexing, and must not be embedded into the concrete (the sand should protect against this) since this would not allow the cable to flex with slab movement.

Phase 4: Finish Surfaces

STEP 4.1

Before beginning work, inspect the mat/cable for damage and secure any mat/cable that may have come loose.

To avoid burying any possible damage that may have occurred since the mat was laid, the following tests should be performed:

Use a digital multi-meter to measure the resistance between the conductors of the mat/cable power leads again (see Step 2.3). If possible, your electrician should perform an insulation resistance test on the mat/cable. A meg ohmmeter (e.g. Megger®) adjusted to a minimum 1000 VDC should give a measured value at least 20 meg ohm (MΩ).

CAUTION: Be prepared to install a marker plate or other identification indicating the presence of ProMelt in the slab. This helps alert and avoid possible damage from future on-site. Install a marker plate where clearly visible in each snow-melted area. A marker plate is placed flush in the wet concrete surface or soft asphalt surface. Other types of surfaces should be made to allow the marker plate to be installed flush with the surface. Do not damage the heating cable.

STEP 4.2

Concrete Application

Pour concrete over the base and ProMelt Mat/Cable so that no less than 1-1/2 inches and no more than 3 inches covers the top of the heating cables. The slab should be a minimum of 4 inches thick total. Driveways normally require thicker. Follow building code requirements for required thicknesses.

CAUTION: Do not use sharp tools which could damage the ProMelt. Blunted shovels should allow you to work the concrete carefully into all areas.

• Make sure the heating cable is fully embedded as well as 2 to 6 inches of the conduits enclosing the power lead and slab sensor wiring (if used).

Allow the concrete to fully cure as required by the concrete supplier. Do not energize the ProMelt Mat/Cable except to briefly test it, as this would improperly accelerate the curing and potentially cause concrete damage.

STEP 4.3

Asphalt Application

If required, apply a prime coat to the first course or untreated base over the top of the cable.

Use 1/2″ aggregate or smaller. Larger aggregate can cut or pinch the cable.

Before applying, ensure the asphalt temperature is not greater than 285°F (140°C). Good compaction of the asphalt requires a certain temperature range of installation, depending on the type of asphalt being installed.

Manually lay the asphalt onto the area. Do not apply with asphalt machines as they may damage the cable. Spread the asphalt so that no less than 1-1/2 inches and no more than 3 inches covers the top of the heating cables.

Compact the asphalt with any power roller as recommended. If possible, move the roller perpendicular with the cable direction to help avoid stress on the cable below. Be careful not to stop or start the roller over the mats as this could cause the asphalt to shift, potentially damaging the cables.

• Make sure the heating cable is fully embedded as well as 2 to 6 inches of the conduits enclosing the power lead and slab sensor wiring (if used).

• DO NOT energize the ProMelt system until the asphalt is fully cooled and cured per the manufacturer.

STEP 4.4

Stone or Paver Application

Manually spread sand over the top of the cables and base so that no less than 1-1/2 inches covers the top of the heating cables. Be careful not to use sharp tools.

Compact the sand as recommended by the paver supplier, being careful not to uncover any of the ProMelt Mat/Cable and not to damage the conduits coming into the slab area. Use hand compacting tools around the conduit area. Add more sand if necessary to maintain minimum 1-1/2 inches over all of the cables and conduit.

Compact the sand as recommended by the paver supplier, being careful not to uncover any of the ProMelt Mat/Cable and not to damage the conduits coming into the slab area. Use hand compacting tools around the conduit area. Add more sand if necessary to maintain minimum 1-1/2 inches over all of the cables and conduit.

• Make sure the heating cable is fully embedded as well as 2 to 6 inches of the conduits enclosing the power lead and slab sensor wiring (if used).

Place the pavers over the top and finish as required. It is highly recommended that pavers be no more that 2-1/2 inches thick.

Step 4.5

Ceramic or Stone Tile Applications

For either application below, exterior-grade materials should be selected and installed per manufacturer’s recommendations. Only vitreous tile (non-porous) tile should be used as other tile will absorb moisture which will lead to failure. The maximum thickness above the cable should be no less than 1.5 and no more than 2.5″. A movement joint should be installed between any heated and non-heated area.

1) Dry-set or Latex-Portland Cement (thin-set) Mortar Application – In this application, the mat or cable is already installed in the concrete slab. The primary concern is to install a cement mortar bond coat (thin-set) and tile according to Tile Council of North America (TCNA) recommendations for exterior applications (F102-07). Mortar and grout materials should be as specified per American National Standards Institute (ANSI) for exterior applications.

2) Cement Mortar or Thick-set Application – In this application, the mat or cable is installed above the structural slab in a thick mortar bed and bond coat according to TCNA F101.07. A 1.25” minimum mortar bed should be placed over the cable or mat according to ANSI A108.1A guidelines. Above this layer, the mortar bond coat and tile is installed.

STEP 4.6

Use a digital multi-meter to measure the resistance between the conductors of the mat/cable power leads again. Record these resistances in Table 3 under “After coverings are applied”.

Phase 5: Controls and Sensors

Refer to Typical Wiring Diagrams page above

STEP 5.1

De-energize all circuits feeding this system before doing any electrical work.

STEP 5.2

If a slab sensor is being installed, uncover the cap or seal on the embedded sensor socket. Feed the sensor leads through the conduit up to the control. Secure the sensor into the socket and finish this installation as required by the sensor manufacturer.

STEP 5.3

Make wire connections at junction boxes for the ProMelt Mat/Cable power leads to the power wiring from the control. If the junction box is located outdoors, it is highly recommended to use wet location rated wire nuts or crimps to avoid corrosion.

STEP 5.4

Install the control at its location according to the instructions provided with the control. Make wiring connections to the power source and to the sensor wires and mat/cable lead wires. Caution: The ground wire supplied with the mat/cable must be connected to a suitable grounding/earthing terminal.

STEP 5.5

After careful inspection of all wiring, connect the power supply wiring to the GFCI type circuit breaker and turn it on.

STEP 5.6

Follow instructions for the control to set it up. The sensor should not allow the system to energize the ProMelt until proper conditions exist. The control may allow you to temporarily test the system for just a few minutes. If you have a clamp-on type electrical test meter, energize the system briefly and verify it is drawing the proper level of current into the mat/cable as

planned.

Do not fully energize the ProMelt, except for this brief test, until the concrete is cured or asphalt is cool. This could cause improper curing of the surface materials.

CAUTION: Do not operate the system with air temperatures above 50°F (10°C) except for this brief test. This will stress the materials and reduce the life of the heating cable and may cause damage to the materials and heating cables.

Problem

Possible Cause

Solution

Mat/cable resistance measurement is outside the range printed on the nameplate label.	An analog ohmmeter (using a moving needle) was used to take the reading.	Obtain a digital ohmmeter (multi-meter) able to read 0 to 20,000 ohms (Ω) and re-measure the resistance.
	If measurement shows an open or short circuit, the heating cable has been damaged.	Record resistances between all power lead wires and contact the manufacturer.
	If measurement is just a little low or high, room temperature has affected the resistance.	Place the mat/cable in a room 65-75 °F and re-measure after an hour.
	The resistance measurement could be from more than one mat/cable.	Disconnect all cables/mats from each other and from controls and re-measure.
	The ohmmeter (multi meter) is set to the wrong scale.	If the ohmmeter (multi-meter) has multiple ranges (e.g. 200Ω, 2kΩ, 20kΩ, 200kΩ, 20MΩ) set the range to 200Ω and re-measure.
Snow/ice is not melting.	Mat/cable has been damaged.	Measure mat/cable resistances between all power lead wires as shown in Phase 3 of this manual. If there is an open or short-circuit damage, record these resistances and contact the manufacturer.
.	GFCI has tripped.	Try resetting the GFCI on the circuit breaker ONCE. If it trips again, do not continue to try resetting it. Check for loose wire connections in the breaker panel, junction boxes, controls, etc. Measure mat/cable resistances between all power lead wires as shown in Phase 3 of this manual. If there is an open or short-circuit damage, record these resistances and contact the manufacturer.
	Incorrect voltage applied.	Briefly energize the system and use a multi-meter to measure the voltage between power lead wires of the mat/cable. Check voltage ratings for each control and cable to make sure they match. If possible, use an “amp clamp” meter to measure the current into each mat/cable.
	Mats/cables are connected in series.	Multiple mats/cables must be connected in “parallel”.
System operates continuously.	Incorrect wiring. Control was “bypassed”.	Check wire connections. See wire instructions with control and in this manual.
	Faulty control. Relay is not opening properly.	Check instructions with the control.

Appendix: Typical Wiring Diagrams

Following are examples of typical wiring connections for the ProMelt systems. Carefully read and follow the instructions given with each control for complete information. All electrical work must be performed by a qualified personnel, in accordance with local codes, ANSI/NFPA 70(NEC Article 426) and section 62 of the CEC part 1.

Enjoy your new SunTouch ProMelt Snow Melting system!

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