Honeywell THR830T thermostat buzzing 30 secs and resetting controls

[Mark Ellis]

Hi folks,

I have the above thermostat connected to a heat only system with a Honeywell Home Expert THR860S controller. When the thermostat switches, I think to on it sometimes buzzes for 30 secs before actually switching on. Sometimes this causes the controller to show random messages i.e. crashes it. Anyone got any ideas.

Thanks in advance.

Mark

 

[AGAS]

ummm fooked stat maybe

 

[Mark Ellis]

Do you mean a forked stat or a damaged one?

 

[Alec_t]

Have you checked all connections are secure?

 

[Mark Ellis]

They seem pretty good. I'll undo them all, clean and try again. It couldn't be to do with anticipator?

 

[D_Hailsham]

They seem pretty good. I'll undo them all, clean and try again. It couldn't be to do with anticipator?

Do I take it that you do not have a connection to the anticipator?

Why did you buy an old technology mechanical stat? Modern digital ones, e.g Honeywell DT90E, provide better control and do not require an anticipator.

 

[Mark Ellis]

I have connected the anticipator but could it cause this problem if I did it wrong? I brought the exact same model as I already had to make the wiring easy.

 

[D_Hailsham]

I have connected the anticipator but could it cause this problem if I did it wrong? I brought the exact same model as I already had to make the wiring easy.

The anticipator, which just a resistor, shouldn't cause this problem. There's no harm temporarily disconnecting the anticipator (terminal 2) and seeing what happens. (The anticipator just reduces the hysteresis - temperature difference between on and off - of a mechanical stat).

For future info, the DT90E wiring is almost the same, apart from not requiring the neutral (terminal 2).

 

[Mark Ellis]

Thanks. I've read it shouldn't be a problem with the anticipator. Think I''m gonna buy a digital one as they are pretty cheap.

 

[Mark Ellis]

Any thoughts on digital thermo Salus RT300?

 

[D_Hailsham]

Salus products do not have a good reputation.