Installation Manual

35
SYSTEM NOT MELTING SNOW
1. Do an amp draw test on the cables to verify proper operation.
2. What is the ambient air temperature?
a. In sub-zero temperatures it is simply too cold to make operation practical. The
system may run all day and night and not melt any snow at 17 degrees or less.
The system can’t generate enough BTUs to overcome the heatloss generated by
very low temperatures.
b. Verify that LOW TEMPERATURE LOCK-OUT is not active on controller. The low
temperature lock-out function disables unit operation in temperatures less than
17°F (–8.33°C) in those climates or during those seasons where it is simply too
cold to make operation practical. The factory default low temperature lock-out
setting is O, meaning that the unit will try to activate the heaters regardless of
ambient temperature.
3. Slab sensor/control (if present) set at too low of a temperature.
Adjust to higher temperature. This will cause the system to shut o prematurely
at a less-than-optimum slab temperature, leaving snow or water present on
the surface.
4. Severe Weather. Manually activate system to clear snow and water. .
a. A very deep snow event will often take extra time to melt. Residential systems
sometimes cannot keep up with very heavy snowfalls. Heavy snowfalls, followed
by very cold temperatures can cause partial melting.
5. Insucient watt density. Verify spacing of product vs the design plan.
a. The more distance between the heating wire, the lower the watts per square foot.
The lower the watts per foot, the less satisfactory the performance. This type of
system will have to run longer amounts of time, and may never melt snow.
6. Wrong voltage is being supplied to heating cable. Verify ohms of heating product.
Do amp draw test to verify proper operation.
a. Is 120V being supplied to a 240V or 277V cable?
b. Do the ohms match the data sheet for installed product?
c. Is the installed product drawing the correct amount of amps?
7. Test ohms of heating product
a. Verify proper ohms per roll/cable
b. Verify no shorts
8. Inspect breaker/reset
9. Inspect wiring and connections inside junction boxes
NO POWER TO HEATING PRODUCT
1. Test ohms of heating cables/rolls
a. Verify proper ohms per roll/cable
b. Verify no shorts
c. Verify no open circuits
2. Inspect breaker/reset
a. Verify proper operation
b. Verify proper amperage rating per install plan
c. Verify proper mA rating of breaker
d. Replace defective breaker
e. Verify use of dual pole breakers for 208 & 240V heaters
3. Inspect Relay panel (if present)
a. Inspect/replace any faulty wiring
b. Inspect/redo/replace any faulty wiring terminals
c. Inspect/replace relay
d. Verify proper trigger voltage entering relay panel/trigger relay
4. Inoperative snow melt controller
a. Verify proper connections and power to controller
b. Verify proper voltage to controller
c. Verify proper setup/programming of controller
d. Test/inspect sensor/s for proper operation (see troubleshooting guide for
controller)
e. Replace defective controller or sensor
5. Wrong voltage is being supplied to heating cable.
a. Is 280V, 240V, or 277V being supplied to a 120V product?
b. Do the ohms match the data sheet for installed product?
c. Repair/replace damaged heating product
6. Inspect wiring between breaker box and control, between control and sensor/s,
control and relay panel (if present), and between relay panel and outside junction
box/es.
7. Inspect heater connections inside all junction boxes.
Snow Melting Troubleshooting Guide