JohnMo

Yep, UK electricity prices are almost purely based on gas wholesale price. As you say until that fact is changed, no change to electric prices, irrespective of cost to actually generate. Trouble is nuclear is the devils electric, with millennium of hidden charges and costs two to three times the gas price, without the hidden costs.

So final update on commissioning. 1. Circulation pump has 3 modes AUTO/ON/OFF. In AUTO mode, the pump speed modulates and it goes off when no call for heat. In ON mode pump runs full speed all the time even when no call for heat. With thick screed and a fan coil, AUTO mode for pump does not work well, flow rate goes down to circa 6L/min and controller can't cope and under and overshoots modulation. It cannot find find the correct running mode. In OFF mode ASHP trip with flow error. Have set to ON and it seems to work well. 2. Control mode can be either dT mode, fixed speed (speed can be selected), or dT control with circulation pump in full speed fixed speed (depending on point 1. and setting to ON above). Have set to dT control. 3. Target dT is selectable, best one my heating setup is to target dT 4. dT2, 3 and 5 didn't respond as well. dT actually sits nearer 2 to 3 but controller seems happy with that. 4. Restart hysterisis, found the controller reacts badly to a premature restart, found I was chasing issues due to forcing a start early. dT4 for restart was acceptable, dT 3 lead to unstable running as the heat couldn't dump heat well. 5. Volumiser in, out or part out of system doesn't make much difference, have left in place. 6. Heat meter reads 0.6 degs higher temperatures, than the Haier controller 7. Final WC curve is 12 OAT 22 flow, -5 OAT 31 flow. 8. Controller set up to use 3rd party thermostat, this allow a 'stove on' over ride, to switch heat pump off when stove is on. It also allows a single switch to move between heat and cool on ASHP and thermostat. It also allows cooling to be temperature driven. Wiring is, from house to wiring centre - 2 core cable for winter/summer change over, wireless switch from thermostat Then from wiring centre to heat pump a 2 core cable to heat pump. No DHW connected. 4 degs outside delivering an average CoP so far today of 5, currently doing 5.2.

Won't make a bit of difference - sorry Why is it difficult to fix, keep building above 16, ideally warmer, then you air movement from outside to inside

That's what you get doing a retrofit. And reusing 22mm Hep2O pipes, 12m each way to cylinder. Original install was combi boiler.

I powered mine from the 3 port valve as it was only needed during DHW. But you may have a zone 1 pump control in your wiring centre? So control as you would if there was a buffer in the system, then call or no call for heat, the main and secondary circulator do the same thing

Titon HRV also sold by Beam under a different badge and lower price point. You can get enthalpy exchangers if you want

So what are you replacing it with? Enthalpy or normal heat exchanger?

Statistics got to love them, but they can produce some rubbish information. You could add minor events like the Russian invasion of Ukraine. Sent gas prices through the roof. Building big nuclear generator, which the tax payer seems to be paying for and also adding to electric bills.

I filled mine with water glycol mix and pressurised - they are not get crushed by anything. My pipes were installed as part of the foundations, so pre walls. Survived a Scottish winter.

I did similar with my super long DHW heating loop. Think it pulled an extra 15 to 20W

185m loop is very long, it will dominate the system pressure drop I removed glycol a year or so ago, system flow jumped from 18 to 22L/min. Add inhibitor and biocide to system, use only one manufacturer for both - do not mix as you may have chemical incompatibility issues.

From the other thread before it closes

Double post?

You quote people to ask other questions or clarification, so it does help

One of the reasons I went for 300mm centres so I could run without mixers. My floor needs approx 32 degs at -9. Go for closer centres, you get to the point where @Nickfromwales comes from. You need a buffer and mixer. So you charge the buffer at minimum acceptable flow temp and then let down the temp to cluster to 20. The other way in milder weather, run heat pump at the lowest temperature that gives you acceptable heat pump behaviour - so about 25 degs and shut the heat pump off once house gets to a defined temperature. You use the thermostat as a energy manager not a comfort thermostat. So set point is just above your normal WC room temperature.

@jimseng not sure how you are doing your quotes but no one gets notified without the user name being included.

Yep Yep

We asked all the contractors at site, how good there signals were, most rubbish, except Vodafone, which was great.

Mean flow temp give an output approximately, if well insulated it's close enough to get you started. But surface temp and mean flue temperature are very different animals. You can have a mean flow temperature of 30 degs and wide pipe spacing and deep screed and floor temp may only be 25 or less. Another attachment is a simple to read graph for screed floor, if you have carpet the tog value will downgrade the W/m² output, tiles little or no effect. No why would you flow at that temp for an output of 370W, your mean water flow is going to be sub 25 degs. Just read off the attached graph for you pipe spacings and output - use a streamline between pipe spacing and go through W/m² to get mean flow temp. Carpets without major care can kill the floor output, especially at low output. If you want carpets get radiators. Or be prepared for poor outputs.

Interesting fact, datasheet says at 30 degs and 2 degs outside the max output is 4.3kW. However if you enable smart grid and use SG1 settings the ASHP pumps out 6kW, while giving a CoP of around 4.5. Reason I did this was to heat the summer house to a usable temperature.

They need line of sight to work well. I would just do 4G/5G if you can. I am on unlimited data for £15 per month.

I would actually step back and ask why? Does your room have adequate ventilation? Above 60% Humidity: In a typical room (20°C), the dew point is approximately 12°C. Since your water is much colder (6°C), heavy condensation is guaranteed. At 50% Humidity: In the same 20°C room, the dew point drops to roughly 9°C. While lower, it is still above 6°C, meaning condensation will likely still form, but at a slower rate. Below 40% Humidity: To completely stop condensation on a 6°C pipe in a 20°C room, you would typically need to lower the humidity to below 40% (where the dew point is roughly 6°C or less) So I would be looking to fix your ventilation, not faffing about with hot water - then your issue will disappear. And you will have a healthy indoor environment as well.

That's easy - but when there are more than two in the house, almost never happens.

We my break it - lets hope not

I would expect seals within the system to complain and not last long with hot water. But @ProDave say 6 lt isn't much draw off from your cylinder - if it's a combi no hope, you'll just use gas and still fill with cold water.