Considering hybrid Air-to-Air and GCH

FreeBear

https://forums.moneysavingexpert.com/discussion/comment/81996532#Comment_81996532

A £500-600 boiler is going to be a budget model with a short warranty period. If you want a decent boiler that will last 10 years or more, you are looking at Worcester Bosch, Viessmann, or a top end Baxi (to name a few). So £1200-1500 plus fitting which will take you up to ~£2500.

Once you get to £4.5K, definitely worth looking at an ASHP and comparing quotes (but not from BG).

zxzxzx

https://forums.moneysavingexpert.com/discussion/comment/81994410#Comment_81994410

True, temp drop here in central south to 2 overnight recently so cop for day down to 3.4. However as I warm water 10-11 the cop then was still just over 4 at about 6 degrees.

Certain that in the depths of winter when the all day temp is low I will achieve nothing like now, but the chances of dropping to 0.9 cop or lower (gas equivalent) for a few weeks would be more than balanced across the longer term….at least that’s what I am hoping for!

Incidentally my flow temp is weather adjusted, cold weather 50 and warm 35 so I don’t really know my actual flow temp.

barker77

If you do go down this route avoid LG. Their mini splits are awful and LG even via CEO office have no interest in making them better.

FreeBear

Incidentally my flow temp is weather adjusted, cold weather 50 and warm 35 so I don’t really know my actual flow temp.

If you run Home Assistant or similar, you can stuff the readings in to a database and produce colourful graphs showing the stats. Apologies if you are already running a home automation system.

Outdoor temperature had been as high as 2.5°C that day (low of -0.4°C at 08:30), and I'd been playing with a flow of 35-40°C just to see if the place would stay warm. Managed to squeeze 94% efficiency out of the gas boiler. In addition, demonstrated that the heating system would run at typical heat pump temperatures and keep the place warm and need 3.6kW to do so. Heating the place up needed up to 7kW with a flow temperature of 50-55°C, so perhaps I need to work on that.