JohnMo

Surface temp has to be below localised air dew point - so not that likely.

When you move in, then declare to your normal home insurance provider, you are still doing xzy scopes.

Would start there, if you are not getting the cooling effects you want (takes a few hours) you can safely go down to 14ish. Look at your UFH manifold, if you start to see water forming, you have gone too low - it should stay nice a dry.

I have an UFH controller with room sensors. It takes a volt free open/closed contact, to switch between heat and cool, have use a similar contact on the ASHP, instead of the controller. Then use a single switch to switch everything between heat/cool. Then use the sensor in the room that gets hottest first to initiate cooling - but I run the house as a single zone, with no actuators on the UFH manifold. I do cooling as a seasonal switch over. So it now on until end of September, but only really comes on when it's needed

Ever moving goal posts - lots of new products to sell. PV has worked for decades on normal UK electrics. But now you can't do it without bidirectional and the correct armoured cable, MCS approved mount systems etc.

Download the manual various ways to switch to cooling

Just download a trial copy of loopcad for doing UFH design.

You beat me to it. I'm closer to 15W/m2 output at -9. Sounds like cosy feet and melted body to me at 40W/m2. The 75mm spacing make my 300mm strange, I still only flow 28 degs max.

It does do cooling, but have to switch between heating and cooling modes. If you are going down to 20 you are in heating mode.

If your heat pump does cooling - not all do. But how are you going to control it? Do your thermostats do cooling? Would set flow temp to 14.5 to 16, fixed flow temp, you want the heat pump to run long cycles. I would have all loops open, so if your thermostats do not do cooling, you will need to fool the system by winding the thermostats to max setting a few hours before you expect to get hot. Do not be tempted to go below 14.5 otherwise you are likely to condensation issues. Would be looking to simplify that.

Very true Very wrong. Just exported 5kWh on the scheme, so should be earning £5.60 in a couple of days. £1 per kWh from the scheme and another 12p from Octopus. I live in NE Scotland. So far with my sign up bonus I am £30 up, in 5 days.

Without an air gap there is zero reflection - if aluminium it just becomes a conductor.

Assuming time of use tariff Direct UVC immersion cylinder - size to suit house bedrooms and storage temp. ASHP, anti freeze and isolate directly on ASHP, pipe through wall flow - direct to UFH manifold isolation valve return, filter and strainer to Panasonic spec, through wall to ASHP isolation valve. That is all the plumbing done. Run in 28mm Hep2O. No Flexi pipes needed. Insulate piping

But we have also had a decade not even looking for it, because what's the point. They just get push back fron further developments. So it's all a wasted discussion

This thread hasn't been making much sense the wording proven reserves. It has defined meaning which doesn't include a whole bunch of oil and gas we know is in the ground. What isn't included Proved Undeveloped (PUD) If the well was drilled to test the reservoir (an appraisal well) and then capped, but bringing it to full production requires a significant capital investment—such as building a new platform, installing subsea pipelines, or drilling additional production wells—it can still be called a Proved Undeveloped reserve. However, it can only be called a proven reserve if the company has a formally approved, commercially viable Field Development Plan (FDP) and a firm commitment to fund and produce it within a reasonable timeframe (typically 5 years). So there are plenty of wells that fit category. The wells may be sour or heavy oil, so at the time not developed further due to low oil price, technology etc. I was involved with development of a reservoir 20 years ago, the oil is still in the ground, the production path was not implemented at that point. So is classed as proved undeveloped - it had a 10 year design life with initial flow of 40k barrels a day. I know of quite a few similar - none are included in the graphs that keep being presented on this thread.

I only stumbled across it at the weekend, think the schemes have been running a year or so. Not convinced by that statement, but the £1 per kWh is in addition to the normal export rate you get from the utility company. So my real rate is £1.12 per kWh. If they lowered the pay out much, the advantages start to disappear and people drop out of the scheme.

But he then said, thanks for only putting those two pipes through the ceiling, that bloke down the road had 21, I kid you not 21! By the way guy two door door down, runs them in a service void, so they are hidden, so well out the way - I can't win all my battles.

I have just signed up for a virtual power plant scheme - doing my bit and getting paid for it. For those not aware when grid is in short supply they pull on your battery and 100/1000s of others. Taking a few kWh and pay me £1 per kWh. Expect to receive £10 a month minimum - but will see how it goes. If anyone wants a referral and get £25 credit to there account send me a message.

Count to 2, have a cuppa or go to pub while other person continues drilling the other 19 holes. Then if surface mounted the plasterer say what numbty put all this pipes here

Still have the same amount of manifold outlets, without the faff of punching loads of holes through between floors. Two holes job done. If you 21 pipes between the upper and lower floor you already have way too much complexity. So saying 21 pipes between floors is not complex, seems a stretch

Just choose a wireless thermostat that switches between cool and heat easily - I say wireless then you can move it to where it gives the best representative house temperature. But the Panasonic controller has one built-in (pretty sure), just use this. It should do cool and heat out the box.

I would simplify. Why not do 2 up and 2 downstairs (1 each hot and cold). Then a single 15mm between each manifold. To make it simple, we do one 15mm to each wet room from each manifold, then branch from there in the wet room.

We used an external permissive to start stop the ASHP. So similar to what you propose. For me knowing what's going on is important, so I have used a wiring centre for the UFH, this is equipped with room sensors, not thermostats. The signal from the wiring centre goes directly to ASHP, not to UFH actuators etc. The whole system can also be moved between heat and cool via a volt free signal. So open circuit is heating mode closed is cooling mode. ASHP using the same signal, so use a single switch to move both the UFH wiring centre and ASHP between the two modes. We have in effect two heated areas the house and summer house. After quite a bit of experimentation figured I could run as a single zone and either the summer house or the house could call for heat, and both got heated together. The house floor acting as a buffer. Running for an hour or so to heat up the summer house has zero effect the house. Have run pure WC and if you can do that, I would, but we have found using the wiring centre and it's sensors, giving the heat pump permission to run, meant we ran better and could keep away from min modulation longer and regularly get CoP of 5+. I would try to run as a single zone, decrease the upstairs output with reduced loop flow where needed. You are going to running very low temps, our curve starts at 26 degs at 10 Deg oat and goes to a massive 28 at -5 degs. So likely hood of overheating is zero. I would make sure price wise you are not being screwed over So MCS uplift and plenty with a profit to make

I needed to top up the system and decided it was too much faff keeping to VDI2035 specs. So dosed with Adey MC1+ inhibitor and biocide.

But for 90% of housing stock they will not be drilling into walls to find out how construction was done or any improvements completed in x years. You may be lucky and they will poke their head into loft, if it has a suitable ladder. They will make a huge bunch of assumptions. Funny old thing just like MCS assessments for heat pumps. We have to most of that now in Scotland, as we need an as designed EPC prior to Warrant issue. Getting those details for existing housing - 90% of the public would not reply, as it's all stuff for someone else to understand.