HughF

Samsung units need an external pump, make sure it’s a PWM one (and connect it to the pwm terminals in the Samsung cabinet) so the heat pump has control over the deltaT

Another ‘value’ proposition that is well supported in the Uk, and is a decent product is the Cool Energy iVT range. Built by SPRSUN in china around a complete lot of parts from Carel, it’s a capable machine with excellent Uk support. £3k for a 9kW unit.

I will admit to being confused about the nomenclature for various types of ventilation, PIV, MEV, dMEV etc. I found the following guide from xpelair particularly helpful so here’s a link, in case others are in the same predicament as myself: https://www.xpelair.co.uk/sites/default/files/xpelair-domestic-systems-brochure.pdf

Partel lunos - very expensive but appear to be premium Prana recouperator - middle of the road Then there is the £149 one from ventilation land… Mitsubishi make a nice looking one, the lossnay system. Looks like the inside unit of a mini split

Staffordshire blue/black engineering brick… Should be just fine. I don’t like non-engineering bricks below DPC although it has been done like that for decades.

I’ve done some research into dMVHR and have a few options on the short list. You’re not the first person who said that the direction reversal type are best avoided. I’m still a little confused as to why there is so much variation in price between manufacturers and their offerings. The Partel lunos is close to £1500!

No top openers in the bedrooms, although I’m going to change the windows out on the rear and will go back to top openers. there is a top opener in the bathroom.

They’re also considerably less popular because you need to find an fgas installer to do the work. A monobloc can be installed by anyone with a bit of plumbing experience.

Bargain…. You’ve beaten me by about £1k, although I’ve got an unvented cylinder in my random pile of eBay parts.

It’s my wife’s house where she lives with her sister. My wife works from home so it’s occupied and heated pretty much 24/7. Single upstairs bathroom, small downstairs kitchen. Indoor air quality and winter condensation is the main issue as we’ve been on a draft proofing and sealing up mission to try and make it less expensive to heat. It is a very exposed end of terrace, on a hill, facing south west, in the south west. I’m sure when it was single glazed with coal fires in every room, it didn’t have a condensation issue. Most of the condensation is on upstairs bedroom windows, so I suspect some upstairs ventilation is required. Indoor air quality has improved since I’ve banned them from smoking inside 🤣 I’m pretty sure the condensation is the result of an increase in clothes drying (she has an open vent dryer in the outhouse, which I’m about to replace with a heat pump dryer) in the house and baths/showers. They don’t cook much.

All interesting points of discussion, thanks. I’ve solved the problem for now by flying somewhere warmer, dryer, and with better building quality 🤣 Back in the hateful UK end of the week though. Back to looking at the solutions to this problem.

101x easier to update the algorithms if they run on AWS instead of having to roll out firmware updates to all the installed units in the field. Trust me, I work in embedded electronics… Personally I don’t give 2 hoots what they do with my temperature data.

Homely is a modbus flow temperature controller, with the smarts (the thermal modelling of your house) and all the flow temperature blocks for the next 24hrs done in software on AWS. You tell it your target room temperature and schedule, it figures out the cheapest way to get there, given the forecast and the spot pricing for your TOU tariff. it takes control of the heat pump, bypassing the built in weather/load compensation. For installers, it gives them a one button commissioning of midea units, as all parameters can be set over modbus, it means they can run the system in weather comp without needing to ever return and tweak the curve following complaints, and the homeowner gets a simple to use interface. It has an internal temperature sensor, an interface unit and a smartphone app.

There’s no way I’m fitting ventilation that doesn’t have heat recovery, blowing cold air in, or sucking out hot air and creating drafts is a total no-no and won’t get past my wife. If it wasn’t moderately airtight then it wouldn’t suffer from condensation, mould and stuffiness, surely? and as for the dehumidifier, I’ve already got two that we use for drying out clothes, but they’re hateful, noisy things that suck 500w (desiccant type)

No trickle vents (2012 windows), exposed location. The house is warm but stuffy. Getting the windows left open isn’t going to happen. I would need a fit and forget heat recovery solution really. No extractor fans anywhere… It really needs a deep renovation but I don’t have anywhere to house the occupants whilst doing the work. Original heating and wiring from ‘86, one double socket in each room. We’re going out the back this year which will give us a bit of space to put the occupants in and do one room at a time.

Did you get a moment to talk to Jack and Chris on the Cool Energy stand? To add another heat pump supplier to your list 🤣 They have a good product…

Background; 1946 end of terrace, block, filled cavity (2”) 300mm loft insulation, double glazing… two persons, 5 cats, gas central heating, flow temp is around 55. I don’t know what the indoor air quality is like but it’s probably poor (I don’t live here at present, just visit occasionally). Anyway, would I need a full Mvhr retrofit deal with the causes of this, or could I get away with just a couple of dMVHR through the wall upstairs. Leaving a window cracked open isn’t an option. *yes, I spent an hour yesterday washing and de-moulding all the windows, and then had a rant at my wife for letting it get this bad - it’s her place.

What an interesting (read, weird) extension... personally I'd go full planning, knock it down and rebuild the floorplan in proper construction to match the original house. Steel frame/glass infill has it's place - in the city

Rendered externally then you can easily go full fill cavity.... Might as well go cellcon/concrete as there's no need for brick internally.

Fit homely, tell it target room temperature, homely learns the WC curve that suits the property and emitters. Makes installers jobs much much easier.

45@-2/-5/-whatever, 37@15 Graham Hendra (freedom heatpumps) came up with it as a good starting point that stops people phoning up and complaining that their radiators don’t feel warm.

@JamesPa you’ve got the Lizzie curve for WC which is a reasonable ‘set and forget’ WC curve, then you’ve got homely which is an automatic WC/flow temp optimiser, you tell it your target room temp, it figures it all out.

Those Uw values are shocking… my cheap and cheerful UPVC supplier can do 0.9 in 3G - I’d have expected better than that from what is supposed to be a premium aluminium product.

I’d keep quiet if I were you… why would you want an uncontrollable hole in your new, sealed, window?

Yes, this is indeed an option for the hinges. I’ve already done it with the latch plates though. I should try and buy some exact replacements really.