HughF

To the OP, r290 mini split from appliances direct, £550. Point the remote at it, heat pours out - as simple as it comes. Appliances direct will also happily sell you an f-has variant if you just pick an installer in your area….. then never call them.

Or they wouldn’t….. remember, most people can barely tie their own shoelaces.

Viessmann are/were made by maxa. And the heat pump division is now completely owned by Carrier… Heard good things about the Panasonic

15m of 32+32 from ingoodnic here on my install, 9kW unit on the end… It was like wrestling a python.

TRVs on the bedroom rads only, mostly set to 3.5/4 out of 6. No zoning, no buffer/LLH/extra pump.

Spot on for my wife, she’s the one who lives there most of the time. Apparently I should have designed for 23 degrees...

Fit the largest radiators you can get away with, in all rooms. You can always turn the flow temperature down… Be aware that flow temps of below 37.5 will result in rads that don’t feel warm to the touch - that might be something you want to consider. I sized ours for 45 flow at -4 outdoors and 21 in the house. It turns out that it rarely gets that cold so the house sits at 22.5-23 most of the time, just running on weather comp 24/7 without any thermostats.

Beware that unlike 16/20/32 pex-al, there are both 25 & 26mm covering the 22 equivalent size.

Personally I’d use chrome press tails with the joint below the floor .

I’ve used twetop brand and geberit, both on 16x2 pex/pert-al and regular continal pex (no al)… No leaks on any of it. I figured if the o-rings seal on the inside and the stuff squashes down, you’re good to go. I generally use WRAS approved UFH pipe for everything… I usually buy end-of-rolls off Facebook 🤣

Do you have a press gun with U jaws? Often job lots of transitions available on ebay for cheap, I’ve got a bucket full… Natural Green Heat do a nice series of push-fit 16mm stuff, fully demountable, fyi…

Rip out timber floors, dig down, hardcore, 200 pir, 125mm conc… Dont waste your time with overlay systems.

Leave it on 24/7 and let it defrost when required. is your Samsung installed per midsummer wholesale instructions or per freedom instructions?

Assume you’ve got rads + ufh? If you’ve just got ufh, ditch the mixers…

I run my ufh at 29.5… 150 spacing in 125mm concrete. I have a mixture of rads (sized for 45 flow at -4) and ufh, so I have to use a mixing station. If you just have ufh throughout then next summer you should consider throwing the mixers in the bin and running weather comp straight off the heat pump flow/return.

Mine is just ‘on’…. The pump is wired onto a 13a socket.

If you’re going to have a thermostat (and yeah, most people will want one), it needs to set the target flow temperature rather than being a crude on/off stat. So you might as well revert to load compensation. Turn it up, rads get warmer, turn it down, rads get cooler….

Not sure what the physical layer is, I think it’s something custom, but it’s designed to re-use old thermostat wiring. quite a few master and slave shields/interfaces are available. I might grab one. The plan would be to read the target flow temperature, calculated by the load compensating opentherm thermostat, from the thermostat. Convert this into a modbus flow temperature packet for the target heat pump, and then send it to the heat pump. A web front end (it would connect to your home wifi) would allow for customisation/selection of the heatpump from the list of those supported.

Sounds just fine, a bit less than us but we do a lot of tumble drying... I think we've done 50 on the whole house today. It has been hovering around freezing and lots of laundry has been done.

This is after 20 mins running this morning….

Yet again another reason why these things need load compensation… I’m so tempted to start on that opentherm - modbus converter I was thinking of building/coding up.

I’ve been away from my system all week and I haven’t had my wife on the phone saying the heating has gone off, so that’s a start…. Back there today so will see how things have been. Will likely remove the nighttime off period 23:30-05:00 now it’s basically 1 degree all the time.

If you tweak the PID interval timer down from 200 secs, it will ramp up much faster…

I’m running 47.5@0 on my curve, and it’s on from 05:00-23:30 on the timeclock. The call for heat is jumpered with a wago. The whole house seems to use around 20kWh/day when we aren’t charging the car or doing the laundry. Add those Into the mix and it goes up to 60. House sits around 20.5-21.5

Yep, rads in the old part and ufh in the new, provided that there is 150mm + of PIR down there. We ended up with 200mm.