@johnmo Interestingly (or possibly not that interesting) but I’ve found a free app called iLet Comfort that has connected to my system and lets me see and control the heating and DHW settings from my iPhone. It also purports to show the COP but I’ve only been using it for a day so that’s to be seen.

We’ve had an influx of new members as we head into the heating season. Welcome everyone.

On that note, if you’ve had a heat pump installed, please can you vote on our poll above.

Octopus - Daikin Altherma 3M 4KW heat pump install - April 2025

My overall experience has been excellent. My house is a fairly straight forward 2 bed mid-terrace with only 5 rads. Heat loss calc was 3.3kw and I had calculated 3.2kw using the Heat Punk website.

I believe I was lucky to get one of the early Octopus quotes to attract customers so I immediately paid my deposit. However the install eventually took almost exactly one year from that date of application through a combination of design changes, planning permission and Octopus process improvements.

Initial survey was long and thorough actually a bit over detailed as the surveyor was new. Second visit was to correct some mistakes and further discuss heat pump and cylinder location. Octopus adamant about installing a Daikin 4KW at the end of the garden (~9m trench) and re-suing the rather small airing cupboard. I pushed for a near house location despite the requirement of planning permission for boundary & noise limits. Plus I wanted to use the loft as the existing storage tanks were sat on a sturdy platform that could be re-used.

Third visit was to confirm new HP location and the viability of using the loft location. By then I'd already made a planning application which was another mini-saga due to three parties making negative comments to my application. I uploaded lots of examples of recent applications plus a nearby 25 house new build estate all equipped with heat pump similar to mine. The planning officer was happy with my application from day one.

Additional requirements from the third surveyor visit included a structural survey and enlargement the loft hatch access. I did the loft hatch myself and boarded all round the hatch in anticipation of the engineers working and hauling the cylinder up to the loft.

Additional visits were mainly electrical checks though I was offered a Cosy 6 alternative during one visit. However a drain cover right by the preferred location quickly stopped that due to the R290 refrigerant limitations.

Actual install took 4 days with a peak of 6 Octopus vans parked on and around my little cul-de-sac. The Octopus engineers were all excellent. One highlight was a discussion between the DNO engineer and the Octopus electrician about who could cut which seal and move which cable within the regulations while splitting the mains supply between the house, EV & heat pump. Bureaucracy!

Only had one follow up as the volumiser became a little noisy after a couple of weeks. Turns out the bleed valve wasn't quite open so an easy fix. The Octopus engineer did a service as well and spotted one rad lock valve was partly closed where they could easily be open in my simple setup. He also spent some time to go through the function and setup of the Daikin.

During the design process 3 of my 5 rads were changed and Octopus stuck to that. I offered to pay for the last two but in the end I just bought a K2 & K3 myself. The K3 was huge and the Octopus engineers kindly helped me to swap that one in the kitchen/diner.

No issues so far though it's mostly been hot water only but I recently enable "pure" weather comp via the Daikin MMI (LWT mode). Installer only menu option.

JT

Thanks @bimbleuk, it must be a difficult location, many visits to get everything perfect we hope. 

Just curious as to whether you had any battery installed? If not, is the pump only running during low tariff periods, or the ROI would not justify a battery?  

@bimbleuk good to hear a good install story!

Posted by: @batpred

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Thanks @bimbleuk, it must be a difficult location, many visits to get everything perfect we hope. 

Just curious as to whether you had any battery installed? If not, is the pump only running during low tariff periods, or the ROI would not justify a battery?  

More like Octopus wanted to fit a Cosy 6 at the end of the garden, avoid planning permission and re-use the tiny airing cupboard. My preference was to install the Daikin 4KW HP next to the house, apply for planning and locate the cylinder on the existing loft plinth. Oh and upgrade all 5 rads while you're at it.

Plenty of to and fro plus some triple checking and from my perspective overzealous requirements. Asbestos testing & structural survey being the most expensive.

Constantly thinking about batteries but solar not worth it as I'd need panels each side to get sun all day. Battery maybe if the HP was expensive, which I'm not expecting. Small house with no outside location suitable. Inside no chance!

Now running "pure" weather comp. No thermostat control. I have a setback for the 4-7pm and night time only. Cosy tariff.