Integrating CM927 with Heatmiser NeoStat System

[BadSquonk]

Hi all,

Newbie here living and working on a cottage renovation. Posts on this forum have already been invaluable and so I thought I'd better join up as I have a heating problem that's not be previously covered!

As part of the renovation we've installed underfloor heating downstairs, which we did ourselves. Through the early part of this year it seemed fine, but after a few weeks I realised that the boiler does not fire when the UFH system calls for heat.

Upstairs we have a rad circuit controlled by a Honeywell CM927 RF stat, The boiler is a Gloworm 35 CXi combi.

Looking carefully through the wiring, the CM927 appears to be wired for burner direct control. The UFH system has a 'request heat' pair of wires, but at the moment it's not working properly.

First, is it possible to connect these up together so that the UFH gets hot water when it needs it?

Second, how would I go about doing this? I'm pretty handy and happy to call in the electricians to make the connections if need be. I just want to get the right technical solution before throwing (more) money at tradesmen who've so far struggled to get to grips with the controls.

Thanks for any help you can give.

 

[Agile]

Because of the different thermal mass of UFH and rads you need separately timed controls.

It is difficult for me to make any guesses as to what you have fitted and thus what you will need.

But any competent heating engineer should have no difficulty in advising what is needed and how it should be connected.

Sounds a bit like a DIY project which has floundered due to lack of experience.

Tony

 

[BadSquonk]

Hi Tony,

Thanks for the reply.

There are separate controls for the upstairs (rads) and downstairs (UFH).

Downstairs there is a Heatmiser UH3 control centre with 4 programmable time zones connected to it. It's all wired up and working correctly, except that it's not getting it's signal for heat through to the boiler.

Upstairs is a radiator circuit controlled by Honeywell CM927. That is working fine.

I believe it's a simple wiring issue, not a heating issue. The timing and programmes are taken care of by the individual zones.

 

[Agile]

The traditional way to provide a call for heat to a boiler is with a motor valve which incorporates a microswitch to activate the boiler.

Tony

 

[BadSquonk]

Tony,

Would it maybe help if I put up some pics of the problem? I've seen the wiring diagram for the CM927 and want to know how to simply connect up the call for heat wires for the UFH. If the two control systems are incompatible, I'm happy to deal with that as the solution.

Or if you know a heating engineer local to Kettering with experience of Heatmiser and Honeywell controls that would also be a good solution!