Ultima357

Thanks for the offer. I'll have a trial with the remote ones, see what results I get. If they work well, it might be possible to make a small bubble to hide these.

Unfortunately in these stats, the face plate plugs into the backplate which houses the psu and 230vac terminals via a multipin connector moulded into the faceplate. Faceplate male, backplate female. Additionally it clips at the top and fastens via small screw at bottom. I did try easing it forward to see how that affected the internal temperature but it just isn't possible. Had iit been possible, it would have been a nice way to improve matters with a vented spacer.

Having looked around, I found some quite neat small enclosures, but instead of adding lumps on the walls, I did a little more probing and found at about 10mm below the unit, the heat it generates is not in play. So ordered some miniature thermistors on 75mm wire tails that I can hook into the remote air sense terminals and just poke them out of the bottom edge. Unobtrusive, safe enough and cheap at £1 each. Guess I could even dab a spot of wall colour paint on them to disguise them some more. Will pester Heatmiser though to do V3 with fully vented enclosure.

Getting air con serviced is absolutely necessary. The internal unit needs cleaning and sterilisation to prevent mould and other nasties taking root. Very different to ASHP where the only internal product is hot water.

I have to laugh at annual service on ASHP. Freedom heat pumps, a major dealer say on their YouTube training channel just to give it a look, check no blockages in the airfins and give the cabinet a clean, then spray with a protective stuff called afx90 I think. Made for boats apparently. Anyone ever service a fridge? Seriously, it'll tell you if it's feeling sick. Under the side panel is another display that I guess will give a fault code if something is seriously wrong. Most seem to be flow errors which is the rest of the system. As for the unvented cylinder, what can you do other than tweak the pressure relief valve to check its not seized?

Thanks for the offer. I'll have a look at what is around, if not I'll knock one up in Sketchup and see what can be done. Trouble is I need 11! (3 are already remote in bathrooms) You can get the ones same size as single gang outlet but they are not too pretty!

True they are mains powered, that's the whole problem. The front panel/thermistor is probably 5v so perfectly safe. It's the heat from the power supply which is behind in the back box that generates the heat. As my trial one hanging out of the bottom is looking good, I'm probably going to wire them in as airsensors, drill out of the back box and pop out below/beside the stat and contain in a neat housing. (I have stud walls, so simple enough). If anyone wants to know, they are 10k NTC thermistors that you need. A few quid apiece max. Less than a quid if you can wait for the slow boat from China.

Plenty of thermistors available. I'm trying one just hung out of the bottom of one of them at the moment which seems to do the job. Like you say, I just need a neat housing to make it look OK. Temping with the 3d printing but just ordered a new toy, a 3 axis cnc router, so may try making something with that. It's accurate to 0.1mm.

These stats are very sophisticated. Each has multiple timers and temperature settings which can be set via a saved profile. Eg a bedroom profile can be applied to each bedroom saving programming separately. The app means you can do this all from the comfort of your armchair, monitor temperature and speed of change, set some of the parameters in the stats too. Being internet connected, you can do it from anywhere too. The stats talk to each other, forming a wireless mesh network which hooks into the neo hub and hence onto the internet. Each is wired to the multiway wiring centres which in turn control the UFH actuators and pumps. ASHP is therefore dumb, just responds to heat call. So overall, I'm very happy with the functionality. It also hooks into Google, Alexa etc, so you can control each room via vouse if it takes your fancy. Some screen shots below.

As a new build with no gas, the difference between oil and ASHP was only about £1000, both with UFH. Or in other words, the same infrastructure but different boiler. Gas would have been £1k cheaper than oil, but the gas hook up would have easily eaten that. Remember that although the oil boiler is cheaper, you still need a double skinned tank these days and they cost as much as the boiler. Oil boiler disadvantage is that they don't modulate the output, they're either on or off. Also remember the RHI and zero servicing of ASHP in your thinking. All adds up. I chose ASHP.

I've talked Heatmiser into sending me a remote wireless sensor which you can pair with the stat, then either use that or average it with the stat. Ultimately though I think a remote head with every one is the solution until someone produces something more sensible. But, with 14 of these plus the hub, changing them out is not a cheap option.

That's the price I found on a quick search for the Honeywell unit, not the Heatmiser.

That is an idea, not sure how practical it is though. The sensor boxes look identical to the Heatmiser ones that they charge £6.50 for....

A cavity wall with full cavity will be circa 1U, maybe lower. With good external insulation you should get down towards 0.2 which will help a lot. The people installing it should give you figures or it should be on your EPC I guess already if you're getting RHI.

Odd things going on with this editor, can't seem to shift previous quote but in response to MJNewton, I appreciate your reply but I have 14 of these, in a meshed array to WiFi hub. At circa 166 quid apiece, changing them all out to honeywell is too eye-watering!

Some may ask why I run the UFH at such high temps. Its a 14 zone, 21 loop system, and as I have a fully insulated slab (300mm of eps and down to 100mm on the perimeter up to dpc) the UFH is cast into the slab of 150mm to 300mm thick concrete. A 155 ton heatstore. So it takes a good push to make it responsive enough for me. Other than kitchen and utility we are fully carpeted at 2 to 2.3 tog.

Just been reading through this long thread as I have the same ASHP and have been slowly educating myself in the mystic art of running one. Simple they are not and the Samsung manuals make quite good fire lighting paper, they are pretty useless otherwise. On the subject of water law or weather compensation as it should be called, I have my 201* settings as 15 and - 2, the corresponding 202* at 40 and 50. Hot water is set to 48 standard and I schedule this to come on between 17:00 and 22:00 as I have solar PV with isolar boost, so any daytime excess PV gets put into hot water and if needed, the ashp tops it up. You should have the immersion hooked into the panel if not done by solar to give the disinfection cycle otherwise it will give the error described. I manually boost mine via the isolar unit if we've had a bad week solar wise. It will show 50deg plus during hw heating, typically 56 ish. I have a 400l tank so ample to use. The heating 0.0 setting is just the offset to the water law, so setting it at - 5 will take 5 deg off the 202* settings as I understand it. I suggest googling Freedom Heat pumps, the main UK importer and looking up their YouTube training videos. They are a mile ahead of the documentation but even then, they had the water law settings wrong (I've emailed them to point this out, but no reply). As for the Samsung panel display of energy use etc, well that too is fantasy. Electric use not too far out though but energy produced gives a COP of 20! Not that's not a typo, it does indicate 20. Just look at the display of daily hours running. Some will be over 24 hrs... It really is a joke. BTW I found mine glugging heat out of the hot water tank overnight in its own antifreeze cycle instead of the buffer tank. Still waiting for an answer from Samsung on this. Meanwhile I've bypassed the hw valve with a manual switch. Pity you can't program it out as I have enough glycol in the system to protect to - 10ish. Your energy use is very high, but non insulated external walls will just bleed heat out as fast as you put it in. I didn't see what they are made of, but old solid 9inch brick walls have a Uvalue of 3 plus. Ten times higher that well insulated modern construction. Mine are 0.1U as is the rest of the house, floor, roof. Windows triple glazed at an average of 0.78U. 253m2 plus another 100m2 of warm attic. My monthly electric bill to 15th Jan was £107. 65" TV too?. Oh, and we run at 23 deg mostly, 22 in bedrooms, hall, utility. No point spending money on heating and still being cold is there? Hope this helps.

I'd tend to think large louvres made out of Cedral or Hardiplank would have minimal air flow restrictions and not affect it greatly, particularly if the back is left open and the louvres are say 300mm plus from the cabinet.

Hi George. I too have a Gen6 Samsung in my new build property. Interesting to see your COP figures as mine just gives out fantasy figures, seemingly thinking that it is running at circa COP 20! This from the control panel. As for over sizing, they run most effectively at lower outputs I believe but may be wrong. I'm currently chasing Samsung on the issue of the anti freeze cycle. Mine wants to take it out of the hot water cylinder instead of the buffer tank, reducing the water temperature by 10 deg overnight in the recent cold weather. So I fitted a bypass switch to take the HW valve out of circuit (I switch it manually). As a passive build, just setting the overnight temps back a degree or 2 means it doesn't run otherwise overnight as we very little heat loss. 12kw model in 253m2.

“notwithstanding the provisions of the town and country planning development order, 1963 no building, structure, or erection of any kind (including walls, fence, hedges, trees and shrubs) being erected or planted on the land within the area hatched in green on the plan without the prior consent of the local planning authority” This is not a Section 4 order which rules out any development. In line with the rest of the thread, the argument lies in which of the two is ultimately the one the council refer to. If they flag back to the original then you clearly have a case for precident owing to the other developments. I don't think their saying precident cannot be an argument. A planning inspector might well disagree with them and you'd win the appeal. The trouble with all this is that it is your money pitted against taxpayers money. They feel no pain.

In answer to the question ofdo they have offset, yes they do, but you still should not have to be calibrating a temperature monitoring device to account for its own heat source. With varying temperature and air flow this will always be a compromise on the true temperature readings. Temp. Yes mine have the same melting wax actuators. But I'm coming back to the problem with the offset. If they are affected by their own internal heat source, the variable volume output of the MVHR will change this offset. Eg, very cold days I turn the MVHR back to just 50m3/hr but after cooking I might boost it to 100 or 220 m3 to remove the smells. Similarly, when my dear neighbour lit a bonfire recently I turned it off completely. This latter action immediately starts all stats climbing higher and you end up feeling cool even though the stats say 22 or 23deg. If everything was stable it might just work but you shouldn't have to be juggling with offsets on a decent piece of equipment. After speaking to Heatmiser, I'm going to try one of their extra wireless sensors linked to the stat to do some testing and temperature averaging. Plus I will try remoting the thermistor. At present, I haven't seen any other device that looks like it would overcome this. The industry seems to be of the opinion that you live with it.

Hmmm. I read through several thousand pages of planning guff to get my new permission in a conservation area. Only took 5 years ?. What you describe sounds like cherry picking by the lpa and subsequent approvals always trump the previous ones as far as I have found. The fact that at 60 years has lapsed is not profound though and it would be a matter of deciding which one of the approvals holds water. A decent local planning guy would be your best bet. Lawyers end up costing a mint and do not know the detail of planning.

No. Mvhr vents are near the windows /furthest from the doors to achieve good airflow through all the room. None are adjacent to the stats, I deliberately designed it all this way to avoid that issue. My original experiment was just using a small paper fan in any case just to move the air. If you probe 20mm below the stat you read say 22deg, push the probe close but not touching the bottom of the stat and it reads 23 or higher indicating heat exiting the housing. In my drilled one, if you probe beside the new holes you read 24 deg...

Interesting. The old design looks sensible to me. The project box solution might be what I end up doing as I'm going to get some 10k ntc thermistors to experiment with.

MVHR can run at 4 different levels too. Comes back to the fact that the MVHR has no effect on the ones with remote sensors, so the ones without are reading/being affected by their own heat source.