Suggestions for a mains powered programmable thermostat

[docboardman]

Hi Everyone!

I've been upgrading the CH system in our house. We have a new system boiler now (Worcester Bosch) and a new DHW tank. I was going to control the tank with a Danfoss TS715, which is already attached to the tank. For CH I wanted a mains powered programmable thermostat. Not happy with RF (too much RF in this house already!) and didn't want to get into batteries, etc.

My original idea was a Danfoss TP7000 for the programmable thermostat. I picked out a site for it and laid in some 5 core flex from the site back to the boiler. (5 core just in case I needed extra wires ...) One problem with the TP7000 is that it won't automatically change from GMT to BST and back.

Then I learned about the Danfoss TP9000. This is two channels so could run both the DHW and the CH. It automatically changes between GMT and BST. Also, it can take the place of the TS715 and use a remote sensor to monitor temperature. My thoughts were to put the remote sensor where the TP7000 was going to go and use the wires there to connect it up to the TP9000.

One problem with this is that when I laid in the flex, I routed it through holes in the joists that also had power cables in them. Danfoss says this will interfere with communications between the TP9000 and the remote sensor. I haven't looked yet at if it is possible to move that flex, but I'm thinking it may be difficult.

So I'm just wondering if anyone out there can suggest another thermostat? I'd like mains powered, could be just one channel, automatically changes between GMT and BST, and not RF.

Cheers,

------------ Doc

 

[stumpydick]

sounds like the sledgehammer/nut scenario.

 

[docboardman]

Okay, I guess I can see that. How to simply?

I think it is probably easier to over engineer then not use most of it, rather than under engineer and not have the capability to adapt. So that is probably why it seems like a sledge hammer and nut.

Having said that - I obviously didn't use a big enough sledge hammer, because I still didn't get it right.

The basic idea, I think, is:

- A programmable thermostat.
- Mains powered.
- Auto GMT/BST update.
- Not RF.

I did my research; looked at Danfoss, Honeywell, Horstmann and some others - and thought I had it sussed. But it looks like I didn't.

So I thought I would ask for some help. I figured that a bit of detail would help with any response.

Hence: sledge hammer and nut.

 

[ChrisR]

Honeywell. Iirc it has a bst/gmt button - not a great diffculty.