How do you know if the UltraHeat® Tank Heater is working?
Turn “ON” the 13.5 VDC power switch for 13.5 VDC UltraHeat® Tank Heaters or plug in the power cord for 120 VAC powered UltraHeat® Tank Heaters. The outside temperature must be lower than 44° F (7° C) before the tank heater will activate (see FAQ above) since all UltraHeat® tank heaters are thermostatically controlled. Check the tank heater after five minutes. Touch the black foam pad in the center of the tank heater, you should feel the warmth from the heating element. This warmth indicates that the tank heater is working properly.