JohnMo

My be worth reading this, not reread it all but may be something of help https://forum.buildhub.org.uk/topic/30786-lg-therma-v-monobloc-ch14-flow-error/

But this mechanism is to protect the boiler, nothing more nothing less. Short cycling is just a quick way to empty your bank balance. You heat the boiler, pipework and a load of energy goes out the flue and maybe you still have a cold house. If you boiler is in that mode, you maybe have way to many zone, badly set up heating system, or another issue, or all the above.

No. Say your inverter trips out at 253V, grid on that day is already at 250V. On the AC side the inverter, it pushes out grid volts, plus a bit, otherwise it cannot break into the grid. If you take all the voltage drops on the AC side the inverter adds volts to make sure it can break into grid, plus it adds the voltage drop. So on a high voltage day your inverter may trip off. It does care what volts it gets on DC side

Run long cables in DC, so they take any voltage drop on that side, (less of an issue for the inverter - doing on the AC side cause high AC voltage and it could result in the inverter tripping. When I did my install PV rated SWA didn't exist, it now does. I ran my cable on the surface - easy to see and less likely to get accidentally damaged. New panels are generally maxing out at nearer 14A. The panels will generate full voltage even in low light, the amps increases with more irradiance. Find a DC voltage drop calculation online, I used I thing 6mm² for about 40m.

So 12 x 285W panels were £700 and had been installed for just under 2 years. Prices have dropped quite a bit

Get some 3x2 timber. Make up some studs either screw to the rear plasterboard from the other side, or screw to metal studs or, bond the timber to plasterboard. Then insulate (sound proof) and finally plasterboard the shower side as normal screwed to timber studs.

The panels I am installing are new. Around £65 each including VAT.

I was in a meeting once (15 years ago) and a guy quoted from Wikipedia - the info he provided was very wrong, he got caught out. Was very embarrassed for a long time. It's reference set is the internet, there is a lot of duff information out there. There lots of good stuff also. Trouble is a few iterations of rubbish, is still rubbish. But if you have a a decent grasp of the subject, you can mark the work spat out, and either ask it to try again or accept it. If you are asking questions about a subject you know nothing about, you've no hope or very lucky.

Definitely in all directions fall away from house, not falling towards house anywhere. What is the wall? Someone elses house or a boundary wall Plank direction is personal choice, but will affect sub structure design If you are using composit boards you will be at 300-400mm centres on the sub structure. I used flat plates 12mm thick and about 200mm wide galvanised steel, sandwiched between timber and then post created in place. The structure needs to be robust, mine was on a new build and designed by structural engineer, so most the wood is 10x2, light duty stuff is 6x2. The perimeter is doubled up 10x2. I

I am similar. Don't really trust it that much, without plenty of interrogation. Asking various questions posed in different ways. Often ask "are you sure" sometimes get the answer yes other times an apology. Generally use it to get information, I could find myself, but it does it quickly, but sometimes on a total tangent.

Well 2 and bit years later the whole array is getting modified. Will keep existing inverter and cables, but installing 12x 445Wp modules, in 2x arrays. The will be mounted on the existing frame, with some steel work being modified. Mainly want to increase shoulder seasons and winter production, and accept some summer output clipping. Got AI to calculate likely clipping losses based on 15p import and export rate and it estimates between £10 and £15 losses each year, all occuring mid summer around midday. So if anyone is looking for 12x 285Wp panels they are for sale.

Think actually building a house and cars don't mix, I put my cars on hold while building, too much head space getting used by doing the house If have curtains automation sorted what happens if the automation system falls over or have a power cut, can you actually open the curtains?

You here plenty of stories - suspect it's the energy company issue rather than anything else. The smart meter comes out the box with E7 already programmed. Then it's a matter of the energy company harvesting the correct data either the overall energy delivery (single rate) or day and night (dual rate). I had no issue with a dumb (no communication) smart meter in either flat or dual rate. When it became smart via a 4G connection, had no issues with E7 or current Cosy tariff. But the issue maybe how the house is wired, which could be a dogs diner, not addressed by the smart meter installer - someone else's job.

I would get a smart meter, you may need to press them for a 4G version. Believe they run on Vodafone, so check if you actually have a signal. A least with a smart meter you can get a selection of tariffs, no smart meter you are just on standard rate or E7.

That's ok but not really how it works. You house has a defined heat loss. The radiators are there as a heat transfer mechanism to replenish the heat lost. The boiler replenishes the radiator. So you start from room heat loss, you specify the radiator for the heat loss and means flow temp through the radiator. You add up all the rooms and that gives you the boiler size. But none of the above really matters, as either the boiler isn't pushing the heat outwards to the heating system, or the heating system cannot accept it due to something physically stopping it. Looking at the datasheet the output of the boiler is 3.5 to 35kW. So pretty good modulation. Flow required through system is well below my heat pump and your piping is well suitable to my flow rates. So unless there is a real issue with the boiler itself, you have the following possible issues Filter clogged A strainer in system is clogged (shouldn't be there if you have a filter) Gate valve added and boiler control is just confused as it doesn't make a difference when pump speed is modulated. Or an isolator valve not fully open. Or piping doesn't match your layout, plumber messed up with pipe routes.

Take some photos of the boiler and any piping especially any valves. Our last house was 3 storey sandstone house almost no insulation and drafty - it was 6 bedrooms etc, we had a 34kW and it never struggled even in the depths of winter in Scotland. From heat geek website if you have an older Victorian or pre-war building with little upgrading — say, single glazing and minimal loft insulation — you should expect 95–110 W/m² (of total floor area, not just ground floor). If the same property has upgraded to double glazing and some loft insulation, this drops to 65–85 W/m². Further upgrades such as cavity insulation can reduce it to 40–65 W/m². Pre-2006 builds or recent full renovations typically range from 30–50 W/m². So look at you total floor area and multiply by watts to get something close to your heat loss.

Don't actually think any MVHR unit needs them, they have in-built frost protection, mine slows the incoming air rate down a little, then when everything is ok goes back to normal speed. This has zero issues at -9. Enthalpy HE help with prolonged cold periods as your house doesn't dry out as much.

Can I ask a basic question, how big is the house and what is the calculated heat loss. For 36kW, it has to be pretty big, uninsulated and pretty drafty. Is this the case? Boiler are pretty simple in a lot respects. They are trying to heat water, the bigger the boiler the higher the flow of water needs to be to move that heat away. The boiler unless told otherwise runs flat out, throws as much heat as it can initially, then if it senses it can, it will modulate output down. The idea is it runs as long as it can. Your boiler will modulate power output and circulation pump speed to do this. Some boiler have a setting (bit like acceleration rate) where you can set the ramp rate, so how many degrees of heat are added per minute, this slows everything down and lets the system catch up. But the WB8000 doesn't have this. What does exist is I believe is Gradient Limitation (Temperature Blocking) The boiler itself has an internal gradient limitation control: It monitors how quickly the flow temperature rises. If the rise is too fast (above a programmed limit), the boiler will temporarily pause the burner for ~2 minutes until it’s safe to continue So you are possibly seeing this in your video. Your circulation pump is a PWM, so it will try to maintain system dT, to within defined limits. To do this on Rising dT boiler increases pump speed, slows it for reducing dT. Your system seems to be fighting this you have what is described as an open system, big pipes, big radiators etc. So unless a valve is closed, you have a blockage or you pump is failing (doubt that). Has the plumber installed something (gate valve or similar) to force a dT against the boilers wish and as such gagged the flow.

Are all your radiator lock shields closed too far, so little or no water flows through system? Are you certain you don't have a valve closed somewhere?

Not sure what you mean here? Disqualified from what?

Maybe for the house AND outbuildings. You can easily run both from a single heat pump.

Dust in the duct etc. I had a Dyson once lasted an hour sucking up building dust (motor failed). It's super fine and gets everywhere. A Dyson is small change compared to MVHR. Another dehumidifier?

A HiSense 4.4kW will come down to 1.8kW at 7 degs, so add a 50L volumiser, you will cycle about once per hour. £2100 delivered, plus you can claim the vat back on a new build. So a little over £1800, volumiser £100 to 150. A heat pump cylinder sized at 45L for each bedroom plus 45L, around £1200. MCS as @Nickfromwales says, will want a standard design, so radiators in each room etc. And still charge an arm and leg. If you size you fan coils correctly your flow.temp will never exceed 35 degs for heating, so you should get a scop of 4.5 or better.

Yep, our longest over hang is about 4m. Basically fixed to two wall plates. Whole roof was engineered by posi supplier and approved by structural engineer. Each end of the house has a 6" steel pole anchored to a big block of concrete, as additional hold down

Trouble with mixers is they mix, so quite a lot of return water goes around the loops again, so inlet water flow rate can be low. So low flow rates a 3kW heater, it's possibly boiling the water.