JohnMo

Mine was way worse than that - it was brown. What are trying to achieve? I didn't power flush, but it took me a few days to get to VDI 2035 spec (read up on it). So I could run without additional chemicals in the water. A power flush will have it all done very quickly.

Yes those are the rules, go to HMRC website its all in there. I had the same conversation and was pointed towards HMRC and thet agreed.

Slight amendment, if you think you will need cooling in bedrooms install fan coils.

We started gas and quickly moved to ASHP. Really wouldn't bother going down the grant route for the ASHP you will just be ripped off with a unit way to big. ASHP like it all kept really simple, this also reduces costs, so no need for thermostats, mixers or pumps, buffers or volumisers, do it all from the ashp circulation pump. So UFH on ground floor and in bathrooms only is a good choice. Keep it to single zone, run 24/7 in weather compensation mode is best way to run in a new build. Make provision for panel heaters in bedrooms. Electric towel rad in bathroom. I would definitely look at Panasonic, easy to install and set up. You need to know your heat loss before progressing. So you need to understand your airtightness and ventilation strategy first. MVHR is for ventilation, if your house isn't going to airtight (better than 3) it's not a good choice, demand activation MEV would be better. Advice, go airtight, really well insulated, MVHR and ASHP. You may not be building a Passivhaus but read up on them, nearly everything is sensible and can be applied to any house. I would steer clear of companies that want to design something and you hand over loads of money for kit you don't really need. Once you get your head around MVHR it's pretty easy to design yourself. Same with the heating system, download LoopCad and design the loops yourself.

No Ours was 10% on acceptance of quote. Balance on satisfaction of completion. No way would I part with the money and leave them with zero benefit to fix anything - if they mess up. You also need to Make sure they are using airtight foam around the window aperture before covering it all up. If you say that's extra, walk away, because you stand no chance of getting good install.

You need to break down what MVHR does Extracts from wet rooms, so all the wet rooms temperatures will be averaged out by the time they get to the HE. But you are only extracting 1/3 to 1/2 the whole house volume each hour. So not much Supply air will pass through the exchanger and basically be within a deg or so if the outgoing air. Again you are only supplying the same volume as you extract each hour. So again not much. You bypass the HE if the outside world is cooler than inside the house, when inside is hotter than outside but at summer temperatures outside (not winter), but you are still changing the air in the house once every few hours. HE bypassing is stop making things worse not really fixing them. Open a couple of windows and you can do several air changes an hour with a cross flow. MVHR is just ventilation don't treat it as anything else. A floor several degrees cooler than the air can suck a lot of heat away. The other day the heat pump was pulling 7kW out the floor for about 1.5 hrs over a 2 hour period, just because the sun was out, it was about 20 outside. But this is really a topic for a different thread.

Possibly a loss leader, they win some loose some, but ultimately they want you buying their electric, they may also be able to lease a car to you?

Yep have MVHR, I also thought MVHR means equal room temps and moving heat about, it doesn't work like that, it's just ventilation. But when the sun's shining it gets hot, MVHR is rubbish at moving heat. Also have UFH in cooling mode, but to get rid of heat quickly opening windows is best. UFH cooling, really just helps bring down the temps quicker than it would otherwise be and tempers the extremes. Our bedroom window is open most of the summer.

Mine issues related to heating a low energy house and early issues I had with excessive gas consumption. Basically way to many thermostats trying to control everything to tightly causes major short cycling. Took awhile to sort. But plumber would have done the same and charged a fortune to install and would have never rectified. Bathrooms really need electric UFH and water UFH House stops needing heat way sooner than the bathrooms do. Would install better bigger opening windows in the spare bedrooms.

After the above, I did a little more fine tuning and ended up Restart hysterisis of 4.9 and shut off hysterisis of 2.8. this suits heating and cooling. Moved the heat pump on to cooling using a target flow temperature of 14.5 at 30 degrees to 15 at 20 degrees, so cooling now also self manages, been on continuously since July, hot day the heat pumps runs 45 mins on and about 20 mins off and a cooler weather doesn't switch on at all, been off since midnight. Costs nothing to run. If it's sunny I need cooling, so PV available.

The heat pump will almost definitely have a flow switch which is activated on a low flow condition in order to self protect. Mine (not mitsubishi) doesn't measure actual flow, I can hook up an external flow meter, if I felt the need, but if it senses min flow via the switch, it shuts down. I have an external heat meter to see what the actual flow is. Are you on glycol? Either way have you checked condition of what is being circulated? If glycol based is it turning into a soup m Looks like steady decline in flow rate, for both the high and low peaks - do you have zones switched off, or heating fluid getting more viscous?

Did a final finish on the water yesterday and today, after leaving the water to circulate for a couple weeks. Did the finish with a slip stream at 0.7L/min through the media. Let it run for about 7 hrs over two days. Final ppm is 114 Final conductivity 236 microsiemen Water looks really clear The above was completed with one fill of Ion Exchange media and it processed around 850L of water. So from brown water with glycol in it, to clear fresh water. This mine, none of the colours but looking more alkaline than acid.

If masking tape is pulling off the coating, they were badly done. I would strip the coating off and redo with a decent primer and top coat. It may be easiest to take the inlet and outlet off the MVHR unit and bag and tape the ends there.

My Durisol ICF finished walls ready for stone slips came in around £12k fully DIY (built in 2020 during COVID). Inside parge coated ready for battens, external ready for battens for wood facing and other walls ready for stone slips. 70m perimeter, wall heights from 2.5m to over 3.6m. No outer skin required, everything direct to ICF. U value 0.14 out the box. Costs breakdown is here https://forum.buildhub.org.uk/topic/19042-takes-less-time-but-is-more-expensive/

Mine is loose while bleeding the system, then I tightened. Then for the next month or so, i released every so often to let any caught air escape, afterwards re tightened.

No

LED downlights come with a transformer that requires just about 50mm gap. So you need to form 50mm service gap. LED lights need plenty of cooling otherwise they fail quite quickly otherwise, so insulated plasterboard may not be a good solution. Once built how are you going to maintain the lights without scaffolding? We moved away from ceiling lights in our lounge (45 Deg ceilings) because they would be so high, you could not get at them easily. Plus they are so far you you they are cr*p. Instead we did combined up and down lights on the wall. But we generally just use side lights only now.

He is possibly burying his head, not really knowing what to do. I would be seeking legal guidance, to block you. You would not be allowed to enter or touch my property. Which include touching my wall you want to build on.

You should design it, ideally with a structural engineer input.

How big is it? What's going in there? Have you planned it out?

And have a garage on your plan, otherwise you can't get it VAT free.

No point starting the journey if you want a house, but can only afford to build a shed. You must have an idea of what you need at the end of the journey? Otherwise you wouldn't even be looking to go this direction. Going underground, even on slope can become a money pit quite quickly - limited funds you need to reduce risk, not increase it. We are a hill and spent £50k before we got out the ground, that is cheap. We spent another £70k landscaping and retaining slope. That's all before we started building. If you think you need 250m², you in reality possible only need 200m² or less. 200m² is big roomy house, 3 double bedrooms with ensuite s, big lounge and kitchen. As mentioned big rooms are difficult and if done poorly look rubbish. Use where you live now, as a yard stick. Are the rooms sized well, need a bit bigger, bit smaller, need twice as big start questioning yourself.as you need a reality check.

We had a similar issue on a gas boiler, the diaphragm had a hole in it, new vessel issue went away

Low energy houses don't need thermostats in every room. When I did our house, I also had a thermostat in every room - guess what, our energy usage was twice as high as expected. Why - short cycling. If you want a thermostats in every room, live with the bills. Heat pumps and third party control equals high bills. Best bet is to let the ASHP just self control, UFH also works best this way. The other alternative is a 2-port buffer with hydraulic separation, this will need to about 70L minus the volume of you smallest zone. You need to control buffer temperature, this should be the only start stop permissive for the heat pump. The heating side thermostats control a suitable circulation pump. This setup means only the flow that has to travel though the buffer does so, not all of it, allowing flow temp to be close to what you need. But your bills will still be higher than no buffer and no zones. I would and have, got rid of all the thermostats, manifold pumps and mixer, all zone valves, buffer, volumisers etc. - certainly in a Passivhaus there is zero need - we now now have none, ASHP is well happy, the floor is self modulating and the heat pump responds well to a need to heat or cool. Cooling at the moment, if the house is hot the heat pump senses this via the return temp and ramps up and runs longer, overnight the ASHP does next to nothing, as no need. Energy consumption, next to nothing at the moment doing cooling. Drive everything direct from ASHP. Just balance the flows to rooms to get temperatures correct and set the WC curve, which should be almost flat. Ours starts at 10 (26) and goes down to -9 (29) - changes by 3 degrees Cylinder heating - Do you have the heat pump set to heat DHW cylinder? Some heat pumps (mine does) work in the following manner. You set the cylinder temp, if the heat pump doesn't achieve the heating in a single cycle it record where it got too and only heats to that level every other time. So example, you set to 55, the heat pump gets to 60 degree flow temp, if it has only achieved 45, it will only heat to 45 then after. So that's one thing to check. To check immersion turn your immersion on - Cylinder should increase in temp if it works - leave for 1/2 an hour. If you have a smart meter the electric consumption should jump by 3kW if it does work. Leak check, he should be able to pressurise the system with a hand pump to very high pressures to find the leak. Leak stop say no, say fix.

Again port a loo. Ground worker provided and invoiced me until I was finished with it, hire company serviced it weekly. Site water was via a 1m3 plastic tank. Which we filled around twice. All concrete was ready mix.