dpmiller

be interesting to see just how much overshoot you'll get with straight on/off control. And how that changes with flow temp too

yep the warmth rising off the floor makes a lower temp much more palatable. but a stat that only switches after a 1c drop and has no accelerator or fuzzy control is going to be hunting massively make/model?

^ chinese clones of those are outstandlingly good value.

Not really, it's only in a week and I'm trying to get some baseline data. But it's only a few button presses to scroll through the current position any time I'm walking past the plant room...

some numbers from mine- which has a variable speed fan, tracking compressor load. At Tamb 4c (measured at the rear of the unit) the coil can get down past-2c. I've set defrost to start at -2c, a little colder than the factory setting. Just before defrost started it looked like this: a thin hoare frost over the whole coil, no obstructive solid ice. By the time the unit went through it's processes- fan off, ramp down compressor, change direction, ramp up, repeat, about seven minutes had passed but the coil had de-iced in half that.

how do you work that out @SteamyTea? the coil will be much cooler than ambient, it's how it works...

you'll get return business and no badmouthing too, Dave. It's not so bad really...

Been playing a bit with the defrost settings on mine- the start of the week was socked-in-cloud wet and around +2c for a few days. Probably about as bad as it gets... But i was able to reduce the duration and end temp a fair bit and still get a good defrost and clearance of water. The steamy puff is much reduced.

I know it shouldn't matter, but have you tried reversing the pipe sensors?

generally one 75mm duct will flow enough to the average room, running two ducts to each plenum offers increased flow or reduced noise, as required.

Like an egg.

google "dewpoint"

The water's p*ssing off my window frames at the moment, but then a tonne of water being driven out of curing screed will do that. I know that it'll get worse before it gets better so I'm keeping the heating on. But that's just me...

if the climate is as damp as you say, 1.5l of water won't make a lot of difference to your woodstore.

the unit has an rj12 cable to go to the controller, plus two sensors- one for the hot tank and one for the buffer/ heating. You can run it like this using it's controller for time and DHW/flow temperature control, it needs nothing more. but... There are dry contact inputs for heat/ DHW/ cooling, and available outputs for aux pump, motor valves, immersion backup. I just pulled in a mains-rated multicore and a screened Cat5 to cover all eventualities; for now that's a pair of the cat5 to extend the sensor up to the tank, and in future two switch wires for heat demand and cooling. One thing I've noticed is that it's quite flow-sensitive. While the flowswitch will let the unit run quite happily at modest flow rates (flowsetter is stuck in Hermes somewhere, boo) the system will throttle the output to keep the flow delta under 10c. Raise the flow, and the power increases too...

the landing/balcony and the two bathrooms upstairs both have UFH. I've ran pipes for rads in the bedrooms but don't think I'll need any, I reckon the heat rising then banking in the screed will keep them about right. Screed is dead-on the 50mm upstairs but the GF is a bit thicker as the subfloor had a bit of variance and I had been erring on the side of caution cf. level access at the front door. 60-75mm...

a few days in and the screed is pushing out a shedload of water again, MVHR has gone into humidity override. Consumption is about 40kWh/day, slab at 22c/ GF 19c/ unheated FF bedrooms 17c. I'm currently running in series/buffer mode, so heatpump flow is going through the TS before heading to the UFH mixer, I've got the heating/buffer sensor strapped to the return pipe after the UFH and bypass, and the ASHP is controlling on that. Flow and TS are both 37c at a setpoint of 30c

Is the radiator clamped tightly in it's mounting brackets? If it is, try loosening a couple a touch.

what wiring centre do you have?

Thanks Clive. So I read the meter. About 4pm yesterday til 8pm today; ASHP, MVHR, and a dehumidifier, minus very little solar production equals 53kWh. And that has the slab up to 19c and the ground floor in general around 17c. That's a shedload more efficient than the willis!

Don't care about the make tbh as it's in a single housing in the meter box. Good spot tho, either A or maybe F? I'll have a mooch around see what I can find.

plenty of room actually Dave, the angle is deceiving (and I'm left-handed lol). It's 10+" off the wall.

you can probably find a setting to change that cycle time?

Just received the SAP and airtightness certification through. House comes out as A96, and the airtightness is as previous at 1.783m3/h/m2 which is 1.37ACH. Well chuffed with that!

IIRC the GSE trays are not much over £30 each, the hold-downs and tekscrews a couple of quid each, and the flashing is worked out per perimeter. And a panel is about 1.5m2... The only other thing you need is some 4x1 to screw down onto in the right zones.