Posted by: @heat-pump-newbie

Very revealing @alastair. Years ago I nearly got stuck behind the bath by squeezing myself round to reach a big hole just as you describe and stuff it with loft insulation. Builders just boxing round the stink pole and  giving no thought to heat loss 🙄. I have the same cold draught coming from the boxing in my current bathroom.

Hi Newbie,

Maybe it is time to get stuck underneath the bath again. 😎 

@alastair welcome to the site. Great description. Check out my Worcestershire ASHP folder here as I used Ecobubl to install a Daikin Altherma 3H HT & Mixergy cylinder at my property. And I’m in the Ecobubl YouTube. They did a great job for us. 
How are you controlling your Daikin?

@julianc Your video with Ecobubl and your posts on these forums helped us decide who to go with and what to get. We are controlling the Daikin using a Salus room thermostat set to 14C overnight, 17C during the day and 19.5C in the evening. The flow temp is set at 45C. It's all working fine for us. We have quite a few SE facing windows, and this morning there was enough sun (before the rain kicked in) and the overnight temperature was warm enough that we had our first day where the heat pump didn't come on first thing (eventually kicked in when the rain was falling).  

Latest blog post - work has been a bit manic and so I've been slow writing this up:

https://ajgdevelop.wordpress.com/2022/03/24/retrofit-6-first-impressions/

The next one will be a bit more about data and cost savings etc.

Thanks for that, @alastair. Apart from the Mixergy cylinder, you've got a very similar setup to us and what you've outlined in your sixth blog post fits VERY closely with our impressions.

We don't currently have an EV, so our usage is inevitably markedly lower than yours. As a result, any excess the solar PV cannot squeeze into the battery during the day is exported via an Octopus Outgoing Agile tariff which is not allowed in conjunction with Octopus Go for obvious reasons. However, given you're saying your EV is being used little enough that you're mostly able to charge from solar, have you done the sums to compare Go (cheap off-peak but no export) with Outgoing Agile (more expensive off-peak but decent export rate)? Presumably you are likely to be covering at least some of that in your next blog post.

@majordennisbloodnok Thanks for your comment. We've not compared the difference between Go and Outgoing Agile directly but you've now got me thinking. I'll see if I can add that into the mix 😎  

This isn't as detailed as some write ups and videos about data to do with renewables and heat pumps, but here is some text (and graphs) about how our house has been doing over the last few months: https://ajgdevelop.wordpress.com/2022/04/14/retrofit-7-first-data/