Bristol ASHP consideration
Posted by: @heat-pump-newbieVery 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?
Daikin Altherma 3H HT 12kWh ASHP with Mixergy h/w cylinder; 4kW solar PV with Solic 200 electric diverter; Honda e and new Hyundai Ioniq 5 N electric vehicles with Myenergi Zappi mk1 charger
@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.
105 m2 bungalow in South East England
Mitsubishi Ecodan 8.5 kW air source heat pump
18 x 360W solar panels
1 x 6 kW GroWatt battery and SPH5000 inverter
1 x Myenergi Zappi
1 x VW ID3
Raised beds for home-grown veg and chickens for eggs
"Semper in excretia; suus solum profundum variat"
@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/
-
Oversized Daikin 9kw
2 days ago
-
ASHP install contract and BUS grant money
6 days ago
-
High air source heat pump running costs – Vaillant AroTherm Plus
1 week ago
-
Savings - using Weather Compensation & Time of Use Tariffs
2 weeks ago
-
Heat Pump starting current
1 month ago
- 21 Forums
- 1,962 Topics
- 42.6 K Posts
- 69 Online
- 2,276 Members
Join Us!
Heat Pump Dramas?
Thinking about installing a heat pump but unsure where to start? Already have one but it’s not performing as expected? Or are you locked in a frustrating dispute with an installer or manufacturer? We’re here to help.
✅ Pre-Installation Planning
✅ Post-Installation Troubleshooting
✅ Performance Optimisation
✅ Complaint Support (Manufacturer & Installer)
Latest Posts
-
RE: Volumisers in Heat Pump Systems: Does Placement Matter?
All agreed. if you want to delete our exchange for cla...
By JamesPa , 3 minutes ago
-
@eliuccio Unfortunately, whilst I agree with a lot of...
By JamesPa , 48 minutes ago
-
RE: Newbie out of her depth – Samsung AE120RXYDEG 12kW heat pump
@bami I think if the heat loss documentation matches a ...
By bontwoody , 1 hour ago
-
RE: What is the best strategy for operating a very oversized heat pump?
@jamespa I'm afraid that's over my head but if anyon...
By IRMartini , 2 hours ago
-
RE: Setback savings - fact or fiction?
And here in case any one wants it is the code I used in...
By cathodeRay , 2 hours ago
-
RE: Samsung Gen 7 R290 12kW is not behaving how I expected
Definitely its in the 20xx FSVs. Conversely it may be...
By JamesPa , 2 hours ago
-
RE: Towel rails. An unexpected final hurdle
We have both Normal Rad for heating the room and then a...
By IRMartini , 4 hours ago
-
RE: Heat Pump Sizing & Installation Costs
Perhaps useful to have installed date too? To get conte...
By Tim441 , 6 hours ago
-
RE: SolarPV tables / online calculator
I'd be interested what others find whilst using that we...
By Majordennisbloodnok , 8 hours ago
-
RE: F.788 Building circuit pump reports internal fault - Vaillant Arotherm
Guess I have to wait for engineer visit. I really hope ...
By jeegnesh , 20 hours ago
-
RE: Act now to defer the UK road tax increase on EVs
@majordennisbloodnok Damn right sir. my attempt at iron...
By Jancold , 23 hours ago
-
RE: ASHP and heating issues in new build house
That’s good gives you more capacity. It made me think, ...
By Terry1812 , 1 day ago
-
RE: Seewet manhole cover within r290 exclusion zone
Thanks! I asked Vaillant, and they say I should be fi...
By dbrb2 , 1 day ago
-
Looking for the Grant Aerona 3 setting to turn off completely at 20 OAT
I'm running my Aerona 3 on WC and the 'warm end of that...
By damonc , 1 day ago
-
RE: Do I just go with the lowest quote for my heat pump?
So after signing in Sept in two weeks the install may s...
By Jancold , 1 day ago
-
RE: Victorian Semi Retrofit / Extension ASHP and UFH Advice
When you are renovating is always a good time, as it ma...
By JamesPa , 1 day ago
-
RE: Just one room not reaching desired temperature
Looks like this issue is now resolved. Aira installed a...
By ChandyKris , 1 day ago
-
There have been several people on the OpenEnergyMonitor...
By RobS , 2 days ago
-
RE: Say hello and introduce yourself
Good point @jamespa But that probably strengthens @ch...
By Transparent , 2 days ago
Latest Topics
-
Heat Pump Sizing & Installation Costs
By Mars 8 hours ago
-
Volumisers in Heat Pump Systems: Does Placement Matter?
By Mars 9 hours ago
-
SolarPV tables / online calculator
By MichelleC 16 hours ago
-
By Toodles 2 days ago