fshr

The musings of a grumpy hairless ape

Heatpump

The System

We’re on our way (again). As of this morning we now have an order placed for a heatpump for the house. We’ve already had the solar in progress for a while now, but it’s taken a lot more effort to get the heatpump organised.

I think the main difficulty we faced wasn’t so much about the products available (they’re pretty much the same), but actually trying to work out what is the right sized solution for us. There’s a lot of information out there on heatpumps, some of which can be conflicting, and there seems to be both a lot of very house specific parts to designing a heat pump and experience based tuning on the part of the designer.

Anyway, we took the option to get 3 separate quotes to compare prices, and we pretty much ended up with 3 different solution designs. Now I’m not someone who can let that be, any OCD I may have means I absolutely need to know the whys and wherefores of not only what’s offered but why? So to get 3 different solutions to (apparently) the same problem was like the proverbial red rag to a bull.

So it took some time…

Two heat loss surveys, numerous emails, visits, and fact checking later, and we’re now at the point where I’m reasonably confident that we’re going for the right system. As a solution, it’s slightly oversized for our needs, but both heat loss surveys put us borderline for the next heatpump size down, and the installer we chose made some good cases for the size we went with.

So what did we go for?

We ended up going with:

That’s spec’d to the MCS standards for our house, which should meet all our heating and DHW needs. By choice we’re also swapping out a couple of radiators with a different model and a towel rail, but that wasn’t a requirement of the install.

For Home Assistant there’s a HACS Integration myPyllant which uses Vaillant’s cloud service to monitor and control the heatpump. That’s likely to be my initial option for integration, but in time I’ll probably look to move to ebusd with a wired adapter (or this). I’m also planning to put both the heatpump and cylinder connections on a Shelly Pro 3EM energy monitor so I can monitor it’s energy usage.

The Install

To come…

Posted 29 May 2025

In SmartHome Heatpump

© Paul Fisher 2025 / CC BY-NC-SA 4.0 / Disclaimer