Thermostat

[thornton_chris]

Hi all,

We have a valliant combi boiler with the following type of digital thermostat...

http://cgi.ebay.co.uk/SALE-Simple-O...arden_Hearing_Cooling_Air&hash=item2eb0081d9d


The heating comes on fine and clicks off when it reaches the right temp but the room then gets quite cold before it finally clicks back on again.

Is this just because it is a cheap thermostat or could it be wired incorectly.

I took the lid off and there is a 3rd wire coiled up behind the thermostat which is un-used. Should this be wired in or is it now redendant?

We used to have a boiler which had a tank in the loft but it was replaced with a combi last year.

Many thanks.

Chris

 

[D_Hailsham]

We have a valliant combi boiler with the following type of digital thermostat

Coronado are just the importers - probably from China or somewhere else in the Far East.

The heating comes on fine and clicks off when it reaches the right temp but the room then gets quite cold before it finally clicks back on again. Is this just because it is a cheap thermostat or could it be wired incorrectly.

Probably because it is cheap! The spec says that the differential is +/- 0.5C, which shouldn't be noticeable, so you probably have one which failed "quality" control!

The third wire is redundant.

Which room is the thermostat in?
Is it near a draught?
Is there a TRV on the rad near the stat?

 

[thornton_chris]

It is in the living room at the bottom of the stairs (stairs come off the living room).

The rad in the same room has no TRV.

There could be a draught coming in from the front door which opens straight into the living room.

Thanks for your reply. At least I know it isn't wired incorectly.

Chris