Can dust in thermostat screw up heating

[Ian G]

My (mechanical) Honeywell also has a single screw. It's on top right hand side and doesn't need to be fully removed ; just unscrew it enough for the head to be clear of the cover. The cover then slips off ( pull from the right hand side first , then disengage at a LHS lug)

I dropped dust into mine whilst repairing damaged plaster above it . The dust/ grit got into the moving parts of the thermostat. It no longer 'clicked' . I think I just blew the dust away. Normal operation was restored

Of course you could also have the added problem of cables being drilled through ..........

(Take the precautions mentioned above ) Ian

[Larry Bud]

Just blow it out with some compressed air.

[John Rumm]

No I did mean older - as in the electromechanical ones that have thermal lag compensating heaters.

Many of the digital ones have batteries for running the digital side, and make no use of the neutral if supplied.

[John Rumm]

It could be the stat has stuck in the call for heat position... then again the heating ought to be working if that is the case.

[Dr. Hardcrab]

Your boiler is up to proper temperature (that's why you are getting hot water). It COULD be your thermostat, but it sound like your circulator is not coming on. That could mean several things. Could be a broken coupler (if it's an older system), could be a bad aquastat/relay, could be a bad motor on the circulator.

You could gently blow the dust out of the t'stat with some compressed air, or do it yourself like you are blowing outa candle. DON'T pour anything into the thermostat! The service guy will be replacing a lot more stuff if you do.

[bdaruvala]

Was really feeling down when promised plumber did not turn up yesterday.

Today luckily he turned up and mainly did cleaning/scratching of points in thermostat and heating turned up.

He did say something about valve being old.

I am tenant of an old man, myself close to 70. When I get frightened the land lord gets more frightened. Will have to convince him to do some upgrade offering to share half the expenses. Hot water tank is plain coper with insulation material tied around it. The boiler does seem to be OK, but the rest can do some upgrade.

I than every one on this thread for picking up my problem and being helpful.

Regards, BarJor.