Dodgy Central Heating Thermostat?

[r8r8r8r8]

I have recently moved into a 2 year old house. The boiler is controlled by an electronic timer programmer and there is a thermostat controller in the hallway. We leave the electronic programmer for the Central Heating "On" at all times and leave it to the thermostat to control when the boiler actually fires up to heat the radiators.

Our rooms are either freezing because the radiators don't come on or only for a short time or very occassionally the rooms are hot and the radiators scalding hot. Most times the hallway is chilly (certainly less that the low 20'sC that the thermostat is set at and need to turn the thermostat up to around 23 or 25C before the boiler gets signal to fire up. Sometimes you can turn the thermostat up as high as it goes (30C) and hear it clicking on but the boiler is not getting fired up. Other times with the radiators and rooms are piping hot when only set as low as 20C.

How can I check if this is a thermostat problem or possibly electronic programmer? We don't have any problems with the Hot Water.

Appreciate any advice given

[r8r8r8r8]

Not a wireless thermostat so unfortunately not as simpel as a battery problem. Thanks

[gucciman]

wouldn't have thought its the programmer as when they go the boiler usually wont fire up at all.
could be the room stat but again when we come across broken ones they usually dont click at all.
could be crap circulating around the system causing problems.
what make and model boiler is it?

[buildersmate]

Sounds like the thermostat to me. Just because you can hear it clicking doesn't always mean the electrical contacts are switching cleanly between open and shut - the contacts may be dirty.
Just to recap, if you say the master timer to set to heat on all the time, the hallway thermostat should then be the device that controls whether hot water gets pumped around the rads or not. Turn it up past the click and the pump (and within a few minutes) the boiler should operate. Turn it down again and the boiler and pump should fire down again.
These mechanical devices are simple and cost less than a tenner. The electronci ones are more expensive. Should be within the scope of a DIYer to change. I'd do that first for a tenner rather than calling out a heating engineer.

[r8r8r8r8]

Thanks gucciman and buildersmate. I will try replacing the mechanical thermostat and see if that fixes it ... that was my initial feeling anyway.

The circulating crap suggestion will be followed next if not resolved