Hot Water and Central Heating question.

[MikeRotherham]

Hi,

I've recently had a new Honeywell ST699 fitted to replace an older ST699 only because the backup battery had failed.

A couple of weeks later I had my boiler replaced with a Viessmann WB1B boiler.

There were no other changes to the system. The boiler was installed onto the existing controls which consist of a room stat and a cylinder stat.

Since then I have noticed that the heating will only turn off when the hot water is turned off either by me turning it off at the controller or the cylinder stat reaching temperature. So even if the room stat reaches temp the heat stays on until the water is switched off.

The water and the heat work ok if either is on by it self.

Does anyone have any idea whether the ST699 controller or the boiler (the way its been connected perhaps) could cause this effect.

The ST699 was fitted by British Gas under my maintenance agreement and the boiler was fitted by a local gas installer. I'm not sure which party to consult first.

I'd welcome any input anyone could offer.

Regards

Mike.

 

[Boilerman2]

You should talk to the person that fitted the boiler as he should have ensured that your existing controls could be interfaced with your new boiler

 

[kevplumb]

"interfaced" ooooooo

but you googled that