Red light on EPU and EPCG heater: if the red light is flashing on and off every second (heartbeat), that means the heater is working perfectly fine.
If the reset does not work, turn off the mains power supply for 10 seconds, then turn it back on again.
Rapid Flashes and then pause (Only for EPU's and EPCG's) - The number of rapid flashes is a fault code
Permanently on (LED on Burners) - Means the burner is locked outland troubleshooting is required. Check for oil pump or gas valve inlet & burner pressure
Green LED lit (Permanent)
If the heater attempts to light 3 times, but fails to maintain a flame, it will go into burner lockout mode as indicated by the red light at the front of the heater being on.
Burner lockout If the heater attempts to light 3 times but fails to maintain a flame, it will go into 'Burner Lockout' mode, which is shown by the red light being on (steady not flashing) which is on the side of the heater.
All unit heaters (suspended from the ceiling) have a lockout reset button. Most controllers (thermostats at ground level) that are installed with unit heater have a lockout reset button on them.
There are two types of lockouts on these heaters. An overheat lockout and a burner lockout.
Press and hold the overheat lockout reset button for 3 seconds and then release. If the heater doesn’t reset, let it cool down for a few minutes and then try again. To speed up this cooling process, manually turn on the main distribution fan. There are three ways to do this:
Overheat Reset Depending on the heater model, there are two different methods for resetting the heater. There will either be a reset button at the front of the heater or on the right-hand side panel of the heater, where, towards the top, there is a red reset button.