mistake_not

Core drills are often diamond tipped if you want to drill a big hole.

Unfortunately the Reverso manual (installer) has no reference to this temperature and was only able to get the info from the manufacturer. Re the Myson you have the installer manual says the fans won't turn on in heating mode unless the flow is 30degrees C. Is this true? *Edit your manual looks like it cracks on if it doesn't detect a flow temp probe.

I'm looking at replacing a couple of rads with fan coils for when we get a heat pump installed in November. Our plan is fully open loop system with UFH downstairs and rads / fan coils upstairs. Heat loss suggests the highest flow temp I will need is ~35 degrees c and plan to modulate flow based weather comp. However, it seems like fan coils (Panasonic and Cool Energy Reverso) have a min flow temp of 35 degrees to turn on. Can't get a straight answer from manufacturers if that's when using the fan coil thermostat, or if it can be manually overridden to just run the fans on low no matter the incoming water flow temp. Anyone got any experience or advice?

Yes, have a 7.5kw generation capacity - could do with more in winter. Have space to get some more panels on the garage so might do that. However with hindsight the thing that actually has quickest payback is battery and night charge in winter at cheap rate.

An option (not saying it's good) is silver foil. Mist spray the glass with water from a sprayer and it will stick perfectly. Just make sure you don't scratch anything.

If you are just doing UFH you should be able to eliminate everything except the 3 port valve to go between the hot water tank / heating (assume you are doing PDHW?) You should have a super efficient system just running the HP flow and return to the UFH (fully open). Obvs if you are paranoid about cookies add a heat diverter (urban plumber had a good vid showing esbe mixer and overheat detector in series) but I wouldn't bother. Only gotcha I can see is making sure you have enough water volume for defrost cycles and ensure you have an expansion tank. (I don't know the cooling set up requirements)

For sure. Also min flow temp if it's a figure given.

Ah that's really interesting to see- thank you. Makes me think I should look at something similar for pumps. Given the price of the quotes I have received a self installation (+sparky) might be on the cards...

Really useful thanks @jack. I took a quick look at the Panasonic unit and on the face of it the specs look good and folks seem to have been able to integrate fully to HA using ESP32. Annoyingly the image seems to have a problem and won't load 😞

Yeah, seems like a 10p resistor they charge £300 😬

So, now that lovely discussion is out the way. Anyone got recommendations for a 5kw pump that does heating and cooling? Obvious candidates are Viessman and Valiant but I know nother about HP manufacturers really. Only requirements other than heating and cooling is integrated into Home assistant so I can keep the cooling point above the dew point, and (probably separately) do weather comp for heating. Plan is a simple open system, no zoning, have enough water volume to not need a buffer, and have bug enough pipework for dt5 flow rates.

Wait x months* and I'll have some data... *Where months may be years....

This is my plan: avoids condensation faff / risk.

I'm going to replace rads with fan coils upstairs. My downstairs doesn't get too hot, so a few degrees reduction via the UFH is good enough. If I get more then bonus 😄

Yeah, the one quote I have had (based around 5kw pump, no rad changes, leaving water tank, but including boiler rip out) is something like 7k after grant 😞. Tempted to see if the sparky that did my solar can do something with me so I get BUS.... I want a very simple fully open loop weather comp system, I already have PDHW and my pipework is all big enough already.