dpmiller

A self-installed sub £1k unit would seem like a no-brainer to me.

and down off it every time the engineer calls?

Yellow Calor butane cylinders are still very popular round these parts

regulator size is one issue, but flow rate at low temps with Butane is a known problem. Not so much Butane used any more tho...

250 bar litres, IIRC.

I'd have to say no, not G3 *but* still requires a safety valve as it's still a stored-volume pressure vessel even if the supply temperature is controlled externally and failsafe. /just like a radiator on a sealed system. The pressure/volume may make it a "pressure vessel" but the rest of the system has redundant controls for temperature and the safety valve is the failsafe for the expansion vessel's pressure control.

you do?

only two people can see the screen without cricking their necks?

With an inverter unit I'm not convinced short-cycling is such an issue ,never mind that the controller should have a delay/cycles per hour setting to assist. But there are many options there in terms of modulation control for sure. Mine has three modes for fan and compressor control somewhat like the Vaillant- Day, Night, and weather compensated. All change the response in subtley-different ways, and then you've got the pump and your chosen deltaT for the system to consider.

I went with Hoymiles microinverters. They work perfectly well standalone, the DTU (equivalent to the Envoy) is only for data logging purposes although it does give the factory access to the devices to for firmware upgrades/ programmable limiting etc; thus the G98/9 requirement . Midsummer don't sell them into the UK any more but they have them on their .ie site. https://midsummer.ie/buy/hoymiles/hoy-mi300 I didn't get a DTU to begin with but have one now and am just awaiting an account being set up for me.

so it wa degassed & regassed to allow a move rather than "new gas" being fitted as some kind of service?

why would you go with a really crappy chinesium inverter @ProDave when a "proper" microinverter isn't much more expensive?

why was the gas "replaced"?

when did you realise your design woudn't fit on the purchased site?

The gypsum screed we went with is extremely stiff and I'd best describe it as being like a council 3x2 paver. Ever tried breaking one of those?

you might try opening it and checking it's strainer too..

get one of these on hire? https://www.arbortechtools.com/en/as170/

and if it is alarm, they tend to have an anti-tamper switch inside..

putting screws in...

surely you'll need an impact driver for the rest of the build?

so your chart is fake then.

"All"? Since when please, with proof.

Poured thinscreeds don't crack at 70mm...

I'm gonna say you'll want more floor insulation as a beam&block subfloor will be chilly...

I went with an inhibited ethylene glycol with reduced toxicity, Thermox DTX.