@alastair smart TRVs are expensive for what you might save (especially given your floor space). Normal TRVs would be fine, just set them to the right number. They will then turn off/turn down the radiator automatically when they reach temperature. However these are pretty useless if you don't close the doors as the house is a closed envelope.

1 - 10°C

2 - 15°C

3 - 20°C (bedrooms)

4 - 25°C (living spaces)

5 - max temperature (use these where ever the thermostat is)

@batalto Thanks for that. I have a feeling that we have a very simple use case and that I'm finding all the really extreme use cases online and trying to force what has been done there onto our house 🤣 . Good to know I can stick with standard controls for now. 

@alastair I think they would be better with big long houses, or mixes of building type. For a normal house I think it's false economy. Mars has smart ones, so I'm sure he can chip in

Posted by: @alastair

Hi all

I'm wondering whether I am over-thinking all of this - I have a tendency to do that and come up with scenarios that would never happen. 

I was thinking that it would be useful and cool to have something like Tado TRVs linked to the radiators when we put the ASHP in (assuming we go with that option). The people we have been getting quotes from say that Tado isn't needed but none of them have explained why not, or how the system they suggest would work or things like that.

So, are smart systems a nice to have, or will they make a tangible difference to the way the ASHP works?

[for info we live in a square box, two floors, 4 beds, built yr 2000, 10mm microbore, radiator heated, standard brick house].

 

Cheers

Al

Hi Al,

If your system works fine at the moment without TRV's, then it may not work any better with them. As far as what would happen if you have an ASHP installed, you may be able to check with your present system. I presume that you have some sort of boiler at the moment. If possible, you could try reducing the water flow temperature coming from your boiler, to the lower temperatures produced by an ASHP. This would allow you to see what effect this has on a room by room basis and also give you an idea of the water temperature an ASHP would need to produce to meet the heat demand of your home.

The lower the water flow temperature that is required, the more efficient an ASHP would operate.

We've gone down the smart TRV and thermostat route @alastair and they work very well in conjunction with a low flow rate system like a heat pump. It can be a bit complicated, and we've covered as much of this as possible in this video:

Posted by: @batalto

@alastair I think they would be better with big long houses, or mixes of building type. For a normal house I think it's false economy. Mars has smart ones, so I'm sure he can chip in

I probably agree with batalto. Smart thermostats and TRVs are pretty cool, and it's great to be able to automate room temperatures based on time of use as opposed to running from room to room turning TRVs up and down – this running around requires a bit of planning if you're running a heat pump because it can take hours for medium-large rooms to warm up. Our TV room is a great example of this. We keep the room on 19-20C throughout the day - at 16:30 we raise the temperature via our smart TRV to 23C so the room is snug by the time we go to watch TV in the evening. It then drops back to 19-20C when we're done.

I haven't done the maths, but I don't think they'll pay for themselves.