JohnMo

You may need to isolate the manifold, depressurise the manifold and take the flow meters off and clean them. This is what they look like internally. A little valve is pushed by a water flow against a spring

If you look at the best performing (CoP and SCoP) on the heat pump monitor, they all cycle quite a lot. It's a normal behaviour.

Low noise mode will reduce output across the board doesn't make it want to modulate more. If you have Homely it's sorting out the running modes. What are trying to fix?

We have UFH through out, all acting as a single zone. I flip about how I run the system, weather compensation and batch charging, but have over the last week been running a slightly elevated flow temp over night (around 32), then using floor as a storage heater (batch charge). But have less UFH pipes in the bedroom so a lower output (or you could reduce flow through those loops). We keep the bedroom doors closed throughout the day, so they don't get as warm, as the rest of the house. So most of yesterday the house had been at just above 21, bedrooms just below 20. By 10pm the house has cooled to just below 21, heating generally off until after midnight. It then starts up again and charges the floor. Heating the floor is a slow affair, so by 0730 the house is back to 21. Just use a simple 0.1 hysterisis thermostat to control. Thing with UFH it's very different to radiators, the change in room temp or house temp takes an age to change. But all done with flow temps are quite lot lower than radiators.

Bit of conflicting requirements - you want to calculate but you also just want 3 phase. Why bother calculating? Although no idea why a domestic house needs 3 phase! If as stated, it could get away with 4kW, would need to do the calcs. We have all you state above, except car charger, our highest 30 mins demand over the last few days including driving immersion (3kW) and heat pump on, MVHR, well pump, treatment plant compressor etc at that point was just over 1.8kWh in 30 mins, so just under 16 amps from a 100 amp supply.

Something like this? There are several ways to setup how the circulation pump runs, yours looks to run based on compressor running. Your heat pump will have a temperature controller which regulates flow temp. The circulation pump looks to be going off with the compressor. The drops in flow rated other than on off is the circulation pump being modulated to maintain flow return differential temperature.

Start by reading building regs. That is always the starting point. Then read passivhaus house MVHR guidelines, they are different but relevant. You need to design based on building regs flow rates as a minimum. Room size is not really relevant it's usage is. Two ducting design method. Branch or semi flexible from a plenum. Semi flexible is way easier to install, no room cross talk to consider. Always look for the longest travel distance between flow in and out points. Depending on your layout coanda effect nozzle can be good. Get a unit that is running at about 50 to 60% of is design rating in normal use. Work out overall flow rates and room rates, the overall in flow will always equal out flow total. A simple guide to flows attached

That should be all you need. If you have trickle vents in wet rooms these need to be always closed. If the are open, the fan just sucks air via these trickle vents and then just blows it outside. Do you have an under cut at the bottom of the bedroom and wet room doors, so air can flow beneath? You only need 5 to 10mm. Then the flow path is in the trickle vents, across the room, under bedroom door, wet room door, across wet room and outside.

No problem

Don't you get E7 tariff on all circuits or just you DHW and storage heaters? My meter only has a single tail going to a single consumer unit. So all cheap rate, or all expensive rate depending on time of day

Go back to structural engineer to seek clarification of the deflection?

We are on E7 it's all done through the single smart meter, no second required, no dedicated circuits, so that could be what's happened also

I would Add isolation valves between mixer and manifold Correct the orientation of the pump and mixer. Form a primary loop between boiler flow and return. Use a close coupled tee to UFH pump mixer

Maybe a bit of a nightmare without lots of deconstruction. And if you don't design correctly may not solve the issues of the whole house What is your current ventilation strategy ? Trickle vents? Fans in wet rooms, intermittent or continuously on etc.?

Air vents are ok when the wind blows, but pretty useless on there own. What fans do you have, and how do they operate? Do windows have trickle vents? How was your roof insulated, what and where are these vents actually ventilating? Basics are You need to establish cross ventilation, so feed in to house from dry rooms and out via wet rooms. The ideal is this all happens automatically and only when needed.

Double post

Did notice a Passivhaus Architect in Forres when I was looking a few years ago. Passive slab, not sure anyone will come this far North, certainly when I was looking a few years ago. I ended up with strip foundations and stub walls and made that thermal bridge free.

Have an Ingersol Rand 1/2 drive impact driver and Ingersol Rand die grinder. Both are not used often, but when I do use the usage can be prolonged. With decent compressor I will also start spray painting. I upgraded my hose a few years ago to the biggest I could find at the time, but will probably replace with a decent hose reel.

But those are not a just a generic statement in a quote as below Hence raising the question or concern.

It seems to say 5cfm at 90psi.

Looking for recommendations After a new air compressor for my garage (man cave, not commercial). Needs to be ok for air tools, not make a racket, single phase, budget? - not break the bank My last air compressor was like this one https://www.halfords.com/motoring/tools/garage-workshop/compressors/sip-v300%2F100-vertical-compressor-675810.html?cm_mmc=Google+PLA-_-Motoring>Tools>Garage+Workshop>Compressors-_-Motoring>Tools>Garage+Workshop>Compressors-_-675810&gclsrc=aw.ds&&_$ja=tsid:|cid:18241192209|agid:|tid:|crid:|nw:x|rnd:2205970339728796520|dvc:m|adp:|mt:|loc:1007327&gad_source=1&gclid=Cj0KCQiAlsy5BhDeARIsABRc6Zvtp8DwvKw1falhYtSayVdUQk7qLs9Gt9tVzKyRmGHOUuvpOgQeuicaAqMyEALw_wcB But wasn't the best, lasted about 5 years before giving up, seemed to be poor driving an impact driver, on anything more than wheel nuts. Any ideas or recommendations?

Before answering the questions what boiler do have? Make and model? Also how many thermostats are you installing 1 or lots of them?

Or would that be return temp? If so the flow could be circa 80 degs?

Couple observations You have a combi boiler, so that will have a recirculation pump, there is zero protection for that pump. It needs a min flow valve or connecting via a close coupled tee. Would question the need for the pump and mixer on the manifold at all, it's doing nothing. Your boiler has a pump and temperature control, it could be direct connected. Run on either weather compensation or fixed flow temp and a thermostat switching the UFH on or off. Basically as set up currently the flow through the system is reversed. It's a bodge. The pump and mixer can go either end of the manifold so that's not an issue, it just needs connecting the current way about. Or as above delete it. Also missing is isolation valves between pump/mixer and manifold. To fix it either the pump mixer assembly needs to set up correctly or delete it.

E7 cylinder costs about 13p per kWh to heat during E7 period. To replace cylinder with a new one will not make it more efficient. Heating on demand without E7 will be closer to 25p kWh, with E7 30p. Unvented E7, would give decent shower performance without the pump. Look on gumtree, Facebook marketplace they come up often for cheap money.