Low voltage to CH programmer

[mattfen]

This is baffling me so hopefully someone can help ! Mother in law's CH stopped today. The Drayton lp522 programmer has gone blank. There is still power to the combi boiler (light on panel) and there is 240v to the fused spur but here is the wierd bit. The power connection to the lp522 ( terminals 1&2) show 36v. Surely this should be 240v? How can a mains system appliance show anything but 240 or 0 when connected to the mains ? (No transformers involved !!). System is in a fully tested and 4 month old extension to the house. Everything ( building, boiler, controls, wiring) is all new. Only today has the voltage to the lp522 gone from 240 to 36 and I don't get it !

Any advice would be hugely appreciated !

Mf

 

[DP]

Voltage you see likely to be ghost voltage ( cross induction due to close proximity to other live cables) seen by a high impedence meter. A low impedence meter will give true reading

240 volt source is missing or broken

It is not uncommon to have a 13 amp fuse, larger rating too, instead of 2, commonly 3 amp or 5 at a push. Under fault condition, fuse does not blow but the programmer circuitry vaporises