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ยป Support LV2 and LV21

Troubleshooting Poor Temperature Regulation
• This page lists problems that may affect the temperature performance of your LUX thermostat with suggested resolutions.
• For more detailed information please refer to the instructions that came with your thermostat.
The instruction manual for this model can be viewed in PDF format by clicking here.
Model LV2 / LV21
Problem Resolution
Heats more than 5 degrees past its displayed set temperature Verify that your thermostat's electrical connections are clean and tight.
Verify that your units placement and mounting are optimum per the installation section of its manual. 
Slowly rotate the dial from full left to full right. Listen carefully for a small click in both directions.  These two clicks should be near the approximate room temperature location on the knob.  NOTE: there will be an additional click heard right near the OFF position on the dial, and the above clicks that are mentioned should be in addition to the click near the OFF position.
Replace unit. There are no user serviceable parts.
No heat when expected Refer to wiring troubleshooting to verify that it is wired according to the units proper wiring diagram. Verify that all connections to your thermostat are clean and tight.
If room temperature is greater than 90F the unit will not close its switch and call for heat.
Rotate the dial to its highest setting. Heat should operate immediately if the approximate room temperature is less than around 90F degrees.
Heat Test Slowly rotate the dial toward its lowest setting. Listen carefully for a small click near room temperature. When it is heard, the unit should switch off heat immediately.  Slowly rotate the dial toward its higest setting. Listen carefully for a small click near room temperature. When it is heard, the unit should switch on heat immediately.
Advanced Troubleshooting This thermostat is designed to switch hazardous voltage. Qualified service personnel may use the following information to troubleshoot the system.
NOTE: Only the L1-IN/OUT pole is broken during normal temperature control.  The L2-IN/OUT pole is a pass-through and is always live unless the thermostat's set temperature knob is in the OFF position (which will break both L1 and L2 poles).
The thermostat uses two snap-action switchs to control heating output. Heating should cease when the room is warmer than its set temperature, and be on when cooler than its set temperature. At its minimum dial position (labeled OFF), both L1 and L2 poles should remain open at any temperature.
For further assistance: Contact your HVAC service company or our Technical Assistance Line if not resolved.