Baxi Wm38/3RS Room Thermostat

It would help if you told us the type of heating system, what is a 3- port valve, where is it located, a HW cylinder, Ch and HW?? If you want help, you have to provide enough information!!!!!

What type of Heating system - Gas fired with HW cylinder?

A 3-port valve is a term in common usage in the UK, and means a valve with 3 openings usually arranged in a "T" shape. Mine is motorised, located under floor boards near the pump and activates when the CH comes on.

Before we even get to that, which may not matter, we should find out what he means by "adding a wireless thermostat"? At one extreme, it could mean just replacing the existing one. At the other, it could mean he wants to control the temperature in another room seperately and in addition to the existing thermostat.

This newsgroup mostly has people from the US and Canada.

You might want to try uk.d-i-y which has some real good people.

They might know what HW and CH are, which you have not explained after being asked.

Currently there are no room thermostats!

We still want to know what kind of a system you are talking about, and what is CH and HW!!!!!!!!!!!!!!!!!!!!

We have some great experts in this group, but we have to know about the base system before we can give meaningful advice!!!!!!!

Could "CH" be Chilled Water and "HW" be Hot Water? In The U.S., many office and institutional buildings are heated and cooled by a glycol and water mix circulating to coils in air handlers that can be mounted in rectangular housings under the windows or in the ceiling duct work. It may be that the OP has a smaller scale system in his home? ^_^

TDD

We'll see if the OP comes back again.