Thanks @jamespa. Much appreciated. I've read that Introduction document a few times and found it very intuitive and easy to understand. Where possible I'm trying to follow the low and slow principle, but clearly something is going wrong somewhere! Will pop a post in the ASHP forum shortly.

@mrfield, welcome to the forums. 

Please go here and start a new topic detailing your issues: https://renewableheatinghub.co.uk/forums/renewable-heating-air-source-heap-pumps-ashps/

Hi all, my name is Julian, and I’m new to the forum. We were planning to make the ASHP switch at some point in the not too distant future, although our timeline has been accelerated somewhat due to our 20+ YO gas boiler giving up the ghost a week or two ago (yep, great timing during the cold snap!). We are making do with some oils filled rads and I’ve wired the immersion through a timed fused switch so we have hot water in the morning. We are based central south (New Forest).

We installed solar and battery in May 2025 (wife had a new EV which helped us make the leap) and really pleased with that setup (19 panels and a single PW3 for now).

So, essentially I’m at the start of the ASHP journey. I’ve reached out to some more ‘commercial’ setups for quotes (Aira and Adler Castra have come back to me so far) and plan to ask @editor for links to local installers. I’m also considering heatgeek but the £250 upfront payment has at least made me pause on that. I’ve spent quite a bit of time reading up via these forums and watching YouTube vids etc.

I’m reasonably handy and well informed on standard plumbing setups (e.g. I DIY installed a three zone UFH setup in our extension a few years ago, partly with an eye on running it low and slow with an ASHP in the future). Anyhow, hello! Open to advice on where to start and what to look out for etc. needless to say I’ve had a go at undertaking a full heat loss survey on heatpunk and think I have a reasonable starting point to work from with quotes and to compare with heat loss surveys done by others.

@jleyland welcome to the forums and thanks for the intro. Email me when you’re ready to get some recommendations near you.

Best thing to do as a next step is start a new dedicated thread for your project, and we can take things from there. 

Hello, I'm a future heat pump, battery, solar and EV owner. Before I move to a heat pump, I want to ensure that I'll get it right, so I made my gas boiler (8 years old~) as efficient as possible. Last summer, I upgraded the radiators and as I track data very carefully, I calculated my heat loss is about 4kW at -3.5 C degree. 

You can see the real time performance here on

1. Emoncms - app view ( https://emoncms.org/app/view?name=MyBoilerIdealLogicH24OpenthermSAT&readkey=1d29c637a4817acdf6e6e271850c9026 ) and
2. Grafana ( https://gasboiler.grafana.net/public-dashboards/8d44381aafa94fe9bdc87839d8845ada )

I have explained some other details about my home and overall system on github - Ideal Logic Heat H24 Real Time Boiler Performance · Alexwijn/SAT · Discussion #40 ( https://github.com/Alexwijn/SAT/discussions/40)

I run daily boiler vs heat pump comparisons and publish results on bsky and x where both properties are almost identical (I found them on heatpumpmonitor.org).

The purpose of all of this was to ensure that I understand what it means to have a well installed system first, before I jump to a new technology. 

Note for the interested: my biggest learning so far is that thermostat controls are more important in a well installed system than it seems, and what's even more surprising, most thermostat controls are pretty bad - even those with weather compensation and some room influence.

Please remember that I'm here to share my findings and I'm all for green energy and heat pumps.

Any questions, please feel free to ask.

Thanks
Adam

Posted by: @freckle-spurred

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Note for the interested: my biggest learning so far is that thermostat controls are more important in a well installed system than it seems, and what's even more surprising, most thermostat controls are pretty bad - even those with weather compensation and some room influence.

Hi @freckle-spurred and welcome.

We would be particularly interest to hear from where you've derived the information which supports that observation.

Please start a new topic and tell us 🙂 

Hi everyone and what a great idea to create a forum like this. I live in Ireland so the eco system here will be different from the UK but hopefully some topics will be universal. The renewables energy market seems more mature in the UK so I’ve been studying what you guys are up to quite a bit.

My case is where my wife and I (both recently retired) are downsizing to a home in the city from our current house in the country. We’ve bought a 1960s 3 bed semi-detached block built house. Our plans are to thermally upgrade the old and extension part to A rated standard along with an air to water Heat Pump and solar panels. An exciting and challenging project. We are expecting to be granted planning permission this week and will enter the builder tender stage. 

In advance of this I’ve had some heating designs done. One by Grant who offer this free service. They calculated from the architect plans that I needed a 12kw heat pump. An independant plumber and a renewables “one stop shop” calculated an 8kw heat pump. I read in many places that sizing the heat pump is critical. 

I wonder what advice might there be for someone who encounters such disparities with this important first step? If it’s better to post this question in a different section I will do that. TIA.

Posted by: @kev1964-irl

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They calculated from the architect plans that I needed a 12kw heat pump. An independant plumber and a renewables “one stop shop” calculated an 8kw heat pump. I read in many places that sizing the heat pump is critical. 

Welcome to the forums, and it's going to be super interesting to see how the install compares to ASHP installations in England, Scotland and Wales.

You're absolutely right about the heat loss calc, and the difference from 8 to 12kW is significant.

Please start a new thread dedicated to your project when you're ready to take this discussion forward.

@editor Hi all I'm Cliff and am based in Cheshire just a short distance from Chester and the Welsh border. We are serial redevelopers and about to undertake our heat pump journey having already put in Solar and Battery Storage, we've had at least one EV in the family for 10 years. I've been following the You Tube channel for a number of years and looking forward to sharing our experiences

@cliffy, hi and welcome to the forums, and we're looking forward to hearing about your heat pump journey. When you're ready, please start a dedicated thread.

Hi all,

Newbi - please be gentle. Got Trianco ActiveAir 5 kW ASHP, , an EV, some pv and batteries.

Have Honeywell Home control with wifi zone control TRV, Mission to discover how to control DHW