ProDave

Turning off the room temp modulation function sounds like the best idea. If I was going to add any automated solar control to my ASHP it would me more along the lines of trying to maximise the time it runs when the sun is out (to use solar PV generation) and shut it down when the sun goes behind a cloud.

That does not sound like a true warm roof. A true warm roof needs insulation above the rafters before the tiles and then you can full fill the rafter space. Clarify with them what they mean by 140mm PIR to slope of truss" To me that sounds like they mean under the rafters but I could be wrong.

So are these actually still legal to install? the one I referred to above was a friend installing it in his conservatory and he was a bit sheepish about it. He said he had been given it because they were "outlawed" and he was fitting it to his conservatory on the quiet hoping nobody would notice.

All that building control in Scotland (at least here in the Highlands) wants for the electrics is an EIC (Electrical Installation Certificate) If you plan to issue that yourself, expect a call from building control to verify your qualifications. You really want to find an electrician that will work with you, let you pull the cables and let him view them before they all get covered up and let him test and certify it.

I used 13mm OSB as a temporary floor. Not so bad downstairs (400mm joist centres) but upstairs (600mm joist centres) it was a bit springy, but nobody fell through it. It all got re used, mostly cut into strips that laid in the bottom of the I joists to support the insulation, and as the first layer over the joists to support the UFH biscuit mix.

I have a 4kW system on an E/W split (hopefully to lengthen generation time rather than optimise total output) I manage to self use about 90% of what we generate, by using the big appliances one at a time in the middle of the day (use a timer if you are out) and by dumping surplus to the immersion heater rather than let it export. The small amount we do export is usually when there is no load to use any, and the generation is >3kW so more than the immersion heater can absorb. In the shoulder seasons the ASHP will help use some but for all the summer that won't be heating the house. I also time the ASHP so it only starts heating the DHW at 11AM when there is plenty of PV generation to use. I assume the quote you had was from an MCS installer? do you feel confident to install the panels on the roof yourself then just get an electrician to connect them? That will be a lot cheaper. Even my DIY installed system will have a payback of 6 years based on how much we are self using.

My view is you are very unlikely to use all you generate from an 8kW PV system. Unless you are installing battery storage (another topic for debate) I see little point going beyond 4kW

The important question: Is this an existing system that has previously worked but has stopped working properly? Or is it new and it has never worked properly? Important because at the moment we don't know if we are looking for a design fault or a part failure.

What exactly are you trying to achieve?

You need a powered distribution amplifier in the loft. Lots of makes to choose from. And it's an Aerial. the other spelling is a washing powder.

It sounds like the flow from the boiler (or other heat source) is way too low. Obvious question, is this new? and has it ever worked properly? or has it just "gone wrong"? More details and photo's of the system please?

Mice if they get in can eat plastic pipes. Just don't let the mice get in.

It will be a "ridge height" limit. PV should not exceed the ridge height. Include a chimney with a TV aerial on with your plans and that is sorted as well.

And why would you need bleach to wash out your wet suit. You didn't did you?

Happy with mine. Engineered Oak, 20mm thick 180mm wide planks laid as a structural board over UFH laid in a biscuit mix. No issues with shrinkage, warping or cracking and no issues with finish. We chose one with a matt pre laquered finish. Could that be what makes the difference? In a previous house we had engineered Oak with an oiled finish and found it a right pain to have to keep on oiling it and being particular how you clean it. this laquered finish board we mop perhaps once a month with a well wrung out mop so not soaked, and there are no issues.

Do you mean an evaporator cooler or proper aircon? I do remember seeing a heat pump aircon unit in a conservatory that worked by taking a tank full of cold mains water in, dumping the heat removed from the room into that until it reached a certain temperature, then dumping that now warm water down the drain to be replaced by another tankful of cold mains water. But I thought those were no longer allowed?

I have replied making it clear to the supplier (and hopefully more likely to get a resolution) that we have scaffolding and the plasterer is offering to rework for free, so it is only materials we need, and importantly technical input to ensure we have not genuinely done anything wrong. The base rail system is a 2 part PVC system by the same supplier that both supports and covers the bottom edge of the wood fibre board and provides a bottom bell cast drip bead. It also incorporates a section of mesh that gets pushed into the base coat. You would have thought that would stop any rain bounce getting in and wicking up. I have not peeled off any affected areas to look, I wanted to leave that until the company rep was here to see for himself.

They blamed being too close to the ground and water wicking up the wall, yes all the way almost to the top of the garage wall. I find that hard to believe. Too close to the ground they quoted 300mm!!!! And they have blamed delamination above a door frame on the wrong type of drip bead. I have replied so I will see what they say. All the render material and beads were supplied in one order from the supplier I am discussing with.

I have appeared to hit a brick wall here. After lots of discussion and sending lots of photos the render supplier has come back and blamed it all entirely on poor workmanship, wrong beads used or too close to the ground. No offer of any help, no offer of materials to rework anything nothing at all. And they have done this entirely from photographs and not from a site visit to actually look at the problem for real. So where do i go from here? Just what am I supposed to do? How do i take this to the next level, legal if necessary? To say I am disappointed would be the understatement of the year. We presently have spent a lot of money on an external wall insulation and render system that has failed. No guarantee that if we rework it it will not fail again. No PROPER explanation of why it has failed. No suggestion what we should do to rework it in such a way that it does not fail again. I need the help of the forums collective wisdom to solve this. In the mean time until this is resolved I have a simple and clear message to any readers. DO NOT UNDER ANY CIRCUMSTANCES CONSIDER A BUILDING USING WOOD FIBRE EXTERNAL WALL INSULATION AND RENDERED WITH THE BAUMIT.COM THIN COAT SILIKON TOP RENDER SYSTEM. YOU PROBABLY WILL BE DISAPPOINTED AS WE ARE AT THE MOMENT. If / when we get a satisfactory resolution to this, I may amend that statement. I hope one day to be able to report how the company has been helpful, caring and we have achieved a satisfactory resolution. That day is not here yet.

I started off allocating a "plant room" I then decided the plant room was the most daft place to put the hot water cylinder as it was a long way from the taps, particularly the kitchen. So the HW cylinder went in an airing cupboard crated in the corner of the small bedroom putting it close to the kitchen, bathrooms and utility room. UFH manifolds are in the utility room downstairs and in a partitioned off bit of the eaves wall in the en-suite. Again central for pipework connecting to them. That just leaves the MVHR and it's manifolds and some heating controls and a pump in the largely empty "plant room" that is now a store room and has my electrical work bench in it.

Wet room. Multipanel on the walls, tiles on the floor. Hinged glass screens just to stop spray splashing too far, that are not very tall and don't touch the floor. Squeegee the lot after use . COLD causes mould. in a warm house never get mould on any surface.

I did not program it. I just observed what happens, when it goes to defrost it turns on the willis heater. It does result in a very quick defrost cycle.

That remeids me when I had the pleasure of 2 weeks in Chicago one January. It was damned cold and lots of snow. When one of the locals said to me "you wait till it gets below zero" it took me a while to realise he was talking of sub zero Fahrenheit.

Yes that's the standard immersion control box, it contains a contactor and a circuit breaker. I don't like your idea of a parallel connection to the immersion heater. Okay IF the person wired it knew exactly what they were doing and it comes from the SAME circuit. What I did was put a switch next to the box that manually energises the contactor in the box, so the immersion heater gets turned on in the same way should you want to use it manually. And further, I added a solid state relay, part of my home made solar PV dump controller, to the box so the SSR bypasses the contactor as well to feed surplus solar PV power to the immersion heater.

I am talking of the Willis heater, inside the heat pump, in line with the heat exchanger. As far as I can tell it has 3 uses: DHW heating it is used in the final stage of DHW heating to get the temperature higher. The default settings on my unit always used this. I changed the settings to only heat my DHW to 48 degrees with a maximum flow temerature of 55 degrees and not to use the willis heater. It is used when the heat pump goes into defrost mode to reduce the amount of heat it has to suck out of the hot water tank. It is used as an emergency heater if some part of the heat pump fails. The only one of those you have any control of is the DHW heating cycle. I don't know if the willis heater is used as well as the immersion heater in the hot water tank for the legionairs cycle as I have that turned off.