combi theremostat

[OlafIrolp]

Ok the only reason im posting this is that im concerned... i have a thermostat and am convinced its not right... posted here before advice get someone to look at it... im certain it reads too low. the boiler Biasi Riva Compact HE MK 2 ... with drayton combi-stat. Two guys looked at it both said two wire. Part of me thinks this isnt right? I read and heard on this forum it may need natural also. Im sure its not accurate. I might be talk **** but if the boiler is coming off on it is doing no good to boiler switches etc. This is bugging me... sorry. Take now i have had heating on nice confortable temp... thermostat is lower.

 

[cagedanimal2010]

you've had two people look at it and given there opinion why don't you think that is right? "it may need natural also" this is not necessarily true, depends on what type of stat, as to weather it needs a NEUTRAL or not.
Danny

 

[topquark]

The combi-stat web page (Combi-Stat Thermostat) says suitable for 2 or 3 wire installation.

However for the biasi riva, the datasheet says 3 wired needed! Here: http://www.draytoncontrols.co.uk/WorkArea/DownloadAsset.aspx?id=4231

 

[OlafIrolp]

The combi-stat web page (Combi-Stat Thermostat) says suitable for 2 or 3 wire installation.

However for the biasi riva, the datasheet says 3 wired needed! Here: http://www.draytoncontrols.co.uk/WorkArea/DownloadAsset.aspx?id=4231

Topquark... you hit the nail on the head! I have seen the same thing... i have e-mailed Drayton also. Saying that the boiler installation manual is unclear i can see how it can be two wired... does not mention 3 wire.

 

[OlafIrolp]

so what is 'N' boiler manual say remove link and connect between 1 and 3 (where link was) no mention of third connection. yet Drayton says yes to 3 connections.

 

[RogertheBodger]

What are you asking for help with? is the thermostat not switching the boiler on and off?

 

[OlafIrolp]

it does... but always reading too low... noticeably low

 

[cagedanimal2010]

it does... but always reading too low... noticeably low

but its switching. how do you know the reading is low?

 

[topquark]

Page 33 of the riva boiler manual here: http://www.biasi.co.uk/images/manua...R_INSTALLATION/4908_User_and_Installation.pdf

Suggests that two wire only is sufficient, check that the connections have been made between the correct terminals on the boiler (not utilising the frost stat position for example).

 

[needasparks]

If its any help I had a Biasi combi a couple of years ago and it was 240v switching from the link so i had to run a 3core with neutral to the stat from the boiler or you will have problems with the stat.

 

[cagedanimal2010]

can we clarify what the problem is? from the information posted, the stat is switching, therefore its working?
A stats job is to sense temp and call for heat yes or no?

 

[OlafIrolp]

whats that a similar model boiler needsaspark

 

[OlafIrolp]

i thin my question is according to drayton installation guide and Combi-Stat Thermostat

and biasi page 34 http://www.biasi.co.uk/images/manua...R_INSTALLATION/4908_User_and_Installation.pdf

how would you wire..

 

[topquark]

Given that the connection for the stat is replacing a link, two wire should suffice IMHO. I'd trust the boiler doc over the stat doc for what's required for the boiler

 

[needasparks]

I can't open the pdf but i would have thought the neutral shunt would have been omited as not all stats require it.
Might help if we knew what stat it was.

Edit
sorry if i knew ! think its only me that cant open file.