Significantly warmer today at 11 degs. Been checking on & off and genuinely this is the figure we've seen a lot of today.


That's what a sub-30℃ flow temp delivers!
Once you have refilled the system air does take about two weeks to separate from what was dissolved in the water. The automatic valves usually work but I had one which stuck and let a load of water out. I now keep the plastic cap on, but release it every now and then to release any air that has built up.
Well spotted and beautifully articulated! The cop/scop thing is only a part of it. The real deal is the annual drop in bill. Add in the PV across the year and 1p to 2p per looks expensive. Add in the export tarriff and we fall face first down the rabbit hole.Stinsy wrote: ↑Mon Dec 16, 2024 7:53 am Most chat when comparing the cost of different heating systems is olongapo these lines:
- Gas at 6p/kWh with boiler efficiency hard to determine accurately. Possibly 60-80% in the real world which makes about 9p/kWh of heat output.
- SH at 7p/kWh with 100% efficiency but the faff of having to predict tomorrow’s weather and charge accordingly.
- HP at 25p/kWh with CoP of 3 makes 8p/kWh of heat output.
So all much of a muchness with the effectiveness of SH understood only by a few.
However your battery means you’re applying cheap-rate electric to the CoP of a HP and you’ve invested in a really good HP installation. Therefore if you achieve a CoP of 5 while using off-peak electric, this results in the price you pay for heat being somewhere between 1 and 2p/kWh.