That depends on a number of variables (like the temperature outside) but generally speaking these snow melting systems are designed to melt 1" - 3" of snow per hour. Anything above 3" per hour is typically considered blizzard conditions.Ā
The material costs are similar. However, electric systems are easier to install, with fewer components and significantly lower maintenance costs. Electric systems will run for a shorter period of time to give the same level of performance but with much higher energy efficiency (typically 95%-98% efficient). Controls and sensors required for the two types of systems are very similar. Electric systems do not usually require slab insulation and do not create the concerns typically associated with hydronic systems. These concerns include, but are not limited to, return temperatures, flue gas venting, waterway shrinkage and property damage caused by leaking pipes or tubes.
When installing outdoor WarmlyYours snow melting cables for your driveway, patio, walkway, terrace, stairs, ramp, etc. - NEVER cross, overlap, or allow the heating cables to touch each other. Doing so will quickly cause a circuit failure due to excessive heat build up. Always follow the installation instructions and/or design layout plan to ensure the cable is installed with the correct spacing required for proper operation.
Our systems can handle low temperatures, but many controls come equipped with a Low-Temperature Lockout Feature. This feature prevents the system from running in very low temperatures. At very low temperatures it can become difficult for the system to effectively melt the snow. It is however possible to turn off this feature should you need the system to keep running during such low temperatures.
The electrician may shorten the cold lead wires during the installation. Any cold lead wire extensions/splices must be made in a junction box in accordance with the installation instructions, and must comply with all national and local electrical codes.
Never cut the heating cable.
This National Electric Code (NEC) required protection for fixed outdoor deicing and snow-melting equipment may be accomplished by using circuit breakers equipped with ground-fault equipment protection (GFEP) of 30 mA. It is important to understand that this required equipment protection is not the same as a 5 mA GFCI used for personal protection.
Power requirements are measured in Amps and based on three factors: the watts per sq. ft. of the snow melting cable or mat, the area powered and the voltage used for the application. Our product is rated at 50 watts per sq. ft., so that is a constant factor. Most snowmelt projects are powered with 240V AC ā not all, but most. The one factor that is always variable is the area to be heated/powered. That is based on your project. For a point of reference, letās use the example above of a 350 sq. ft. concrete patio.
The formula is (50 W/sq. ft. x area of 350 sq. ft.) / V (240V) = Amps, so 17,500 / 240V = 72.9 Amps
All of our automatic controllers have a Hold-on time feature after the initial warming up of the snow melt system. This feature ensures that all the snow is melted from the surface, and also that the system continues to operate and evaporate the surface water without it refreezing.
The heating elements for a snow melting system typically will start at $9 ($11 CAD) per sq. ft. for Snow Melting Cables and $11 ($14 CAD) per sq. ft. for Snow Melting Mats. However, you'll also want to keep in mind the cost of a control, and if required, sensor/s for your snow melting system, which will add to the cost. Use our free Quote Builder to get an idea of how much a system would cost for your project.Ā
Pavers can be removed and reinstalled for a retrofit application of our snow melt system. Tire tracks are not typically recommended for paver surfaces, so any retrofit application would most likely need to be full coverage. In this case, it should be treated like a brand new installation, just with existing pavers.
To ensure optimal performance, snow melting heating elements should be installed so that they are consistentlyĀ 2"-3" from the finished surface. For installations using pavers, the maximum thickness for pavers installed over heating elements is 2.5".Ā
Yes, you can retrofit a snow melting system into a preexisting driveway made of concrete or asphalt. You can do this by using an appropriate tool to cut properly spaced lines (or trenches for tire tracks heating) in the surface. Then you can place the the heating elements in the lines (or trenches) before sealing themĀ with either hot asphaltic sealer for asphalt retrofits, or backer rod and expansion joint sealer (SikaFlex or similar) for concrete retrofits. Of course, you'll want to make sure this step is done in accordance with the filler manufacturerās recommended procedures. Check out our snow melting retrofit guide for more information about this process.Ā
If a cable is damaged during installation, recheck the system for continuity and confirm the integrity of the insulation with a megohmmeter, or "megger" tester, referring to the installation and testing instructions. If the cable fails any of these tests, take the following actions: clear a 3 foot square working area around the damaged section of cable, and record the cable part number from the UL tag and the location where you purchased the product. Call WarmlyYours with the above information. WarmlyYours will provide further assistance and supply a splice kit suitable for repairing the particular cable.
To calculate the system's approximate operating costs, multiply the total kilowatts of the system by the cost per kilowatt in your area. Let's use the example of a 350 sq. ft. of concrete patio (residential application), with 240 VAC.
Total Watts:Ā multiply area in sq. ft. x 50 Watts
350 x 50 = 17,500 Total Watts
Kilowatts:Ā (the unit in we purchase electricity) take the Total Watts and divide by 1000
17,500 Total Watts / 1000 = 17.5 Kilowatts.
Kilowatt Rate:Ā use the national average of .12 cents per Kilowatt-hours so how much do we pay for 17.5 kWatts?
17.5 kW x .10 = $1.75 for every full hour of operation.
Hours of Operation:Ā We use a typical 6 hour snowfall for our example.
$1.75 x 6 hours = $10.50 for that snowfall.
All of this will vary due to "after-run time". "After run time" is where the system remains on extra hours after the snow has completed falling, to ensure complete pavement snow melting and drying.
Yes, as long as the paver isn't resting on exposed cable. The cable has to be embedded according to the installation cross section drawing.
Cover to an uncompacted depth of 1.5ā (38mm), leveled to grade. A compactor that's applicable to the thickness and application can be used to compact the sand. The paver installer(s) must take care not to walk on the hot-cold factory splice and to avoid damaging the Heating Cables with shovels or rakes. At no time shall the compactor directly contact the wire.
Yes, but the cables will have a slightly reduced heat output. The wattage will be 13% lower, so that means instead of 50 Watts per Sq. Ft., the system will provide around 43.5 Watts per Sq. Ft. That is why WarmlyYours now stocks 208V cables."
Always confirm the power requirements with the electrician. Large snow melting systems usually require a new electrical panel or electrical service. Contact WarmlyYours for a quotation, indicating the actual power capacity available, and to obtain recommendations for reducing the power consumption. For example, opting for tire track coverage rather than installing the snow melting system over the entire driveway can dramatically reduce power requirements.
Yes. Ā Information on how to install under permeable pavers can be found in section 4.6 of the Installation Manual
. Ā Excavate 18ā and fill with #2 aggregate/stone.
. Ā 4ā of #57 stone
. Ā 2ā of #9 stone to serve as the paver setting bed.
. Ā The heating cable is installed within the #9 stone layer.
To maximize the amount of heat transferred from the heating cable to the pavers, theĀ stone separating the cable and pavers needs as much contact with both as possible. Crushed stone with fines transfers the most heat, butĀ doesnāt drain, so it isnāt used in a permeable installation. Instead, smaller drainage stone (#9) is used because it has more contact with theĀ cable and transfers more heat than larger stone.
Note:Ā do not install the cable at the top so itās touching the pavers. Potential movement by the pavers over time could wear through theĀ protective coating of the cable and short out the entire installation.
Once you've decided what type of heating system (manual vs. automatic), you'll need to choose a control, which may or may not utilize a sensor. You may need a relay panel(s) depending on the size of the system, and a snow melt plaque which is required by the National Electric Code. Junction box(es) may be optional depending on the distance of heating cable from the indoor power location.
Yes, WarmlyYours Snow Melting Heating System can be installed with quartzite stones. Start with 4ā to 8ā (102mm to 203mm) of crushed rock aggregate base. Rebar or wire mesh should be staked on top of this base and then heating cables or mats will be tied to this mesh with plastic zip ties. Heating system needs to be covered with 1ā to 1.5ā (51mm to 76mm) of finished mortar or sand. Stone Pavers will be installed on top but must NOT be any thicker than 2.5ā (63.5mm). See cross-section in the documents section and in the manual.
The snow melting system is not operated by a thermostat, it is operated by either an automatic or manual controller.Ā AĀ snow melting controller does not maintain temperatures like an indoor thermostat does.Ā An automatic snow melting controllerĀ only turns the snow melting system on when it detects precipitation and the temperature outdoors is below the set temp (typically 37.4Ā°F / 3Ā°C).
A properly designed and installed system will handle most snow melting demands. Some snow events may have a very rapid snow fall rate, and some may not. No 2 events are ever exactly the same. Our system typically can melt 1ā-2ā of snow per hour, on average. However, it is important to understand that a system may not melt snow at very cold temperatures. This is simply because the system cannot generate enough BTUs to overcome the heat loss generated by very low temperatures.
In order to estimate cost of operation, the Warmly Yours Electric Snow Melting Operating Cost Calculator is a useful tool that can help illustrate what it would cost to operate the system.
No, chicken wire is too flimsy. A rigid framework without sharp edges, such as rebar or wire mesh, needs to be used to ensure that the embedded heating system is the proper distance from the finished surface. We recommend that the heating system is secured to the rigid framework with plastic zip-ties.Ā
No, a sensor is not required with the snow melt system. However, certain automatic controllers require a temperature/moisture sensor to sense atmospheric conditions and may also require an in-slab, high temperature limit sensor to be installed (notably, asphalt installations).
When heating stairs, we recommend minimizing or eliminating overhangs/lips on stair surfaces. It is very difficult for the heat to reach these protrusions, as heat only transfers, at most, 2" to 3ā laterally from the cable. This is why we recommend placing a run of the heating cable right at the front edge of the stair, which will help keep this area clear of snow or frost as much as possible. The riser of the stair is not heated--only one run of cable goes down the riser to reach from an upper stair to a lower stair.
Yes. The NEC requires 2ā minimum of non-combustible material below, and 1.5ā minimum of non-combustible material above the heating cable.
The drawback is whether or not the pervious concrete will fail under load, thereby damaging the heating cable and voiding warranty. The cable should be attached to rebar in this case to insure the strongest support.
The best time to install an asphalt driveway is generally from spring to fall. The contractor has more time to work with asphalt at warmer temperatures of 50Ā°F / 10Ā°C and above. The warmer the better. The contractor has less time to work with asphalt at colder temperatures and lesser depths. For example, at 40Ā°F / 4Ā°C, a contractor has only 25 minutes to work with a 2" thick asphalt installation.
This feature prevents the snow melting system from running, by default, in temperatures below 17Ā°F (ā8.33Ā°C), or as set by the user. At temperatures this low, it becomes difficult for the system to effectively melt the snow. It is, however, possible to turn off this feature should the system be required to keep running during these low temperatures.
The correct bedding material should be washed concrete sand meeting ASTM C33 gradation.Ā Ā
Please review this WarmlyYours Snow-MeltingĀ cross-section for proper installation.