Honeywell L641A1039 fitted to outside of cylinder controls a pump that feeds 3 towel radiators This stat only switches pump on when at lowest setting of 40C Heating is from a wood burner.
A pipe stat Honeywell L641B1012 is fitted to the outlet pipe at back of woodburner, it controls main pump for central heating . this pump is on most of the time and switches off when the set temperature is reached. I have just renewed the stat. There is also a Motorised valve in the system V4043B1265. Have the wrong Thermostats been fitted. Installer no longer available.
A pipe stat Honeywell L641B1012 is fitted to the outlet pipe at back of woodburner, it controls main pump for central heating . this pump is on most of the time and switches off when the set temperature is reached. I have just renewed the stat. There is also a Motorised valve in the system V4043B1265. Have the wrong Thermostats been fitted. Installer no longer available.
