HughF

Remove the stupid planning restrictions around outdoor condensers and just pivot to air-air for domestic heating - much cheaper, easier to fit, f-gas industry is already existing and the units are already ‘smart’ out of the box which apparently people want these days. Oh, and they cool out the box.

Even if we do, it’s far more efficient to burn it in a CCGT, transmit the energy to the home as electricity, then run a heat pump with that electricity than it is to pipe the gas and then burn it in the home. Breakeven point for efficiency is a scop of 2.8 iirc.

We could use the same logic with taxi drivers - Taxi drivers don’t buy premium cars. They buy cars that give them minimum cost of ownership whilst doing the job they need to do. The big house builders fit the cheapest thing that does the job. Generic 70mm uPVC, minimum cavity insulation, ideal logic combo boilers. I’m not talking about the people who frequent this forum and build ‘decent houses’ - I’m talking the big national house builders where it’s all about maximising profit whilst just about complying with the minimum standard set by BR. They’d fit electric panel rads because they’re dirt cheap.

If you didn’t mandate it, the house builders would just fit electric panel rads as they’re cheaper. House builders always aim for the cheapest option.

And that is how it should be done….

That’s a good place for it. A lot of other manufacturers already have flow temperature sensors installed internally so even when you do run them with a buffer/llh/plate/whatever you don’t need for an extra temp sensor. SPRSUN doesn’t have an internal sensor so the buffer probe needs to go somewhere.

Pretty much, yep…. the new grant r290 hydraulic schematic appears to be properly designed (no buffer, no trv heads, single zone)… most of the others I’ve seen are just standard buffer + secondary pump. Especially Chinese ones.

Standard SPRSUN design choice - commonly used in China where electricity is cheap and they’re competing against direct electric heat so any cop is a good cop. I see it in 75% of the Vaillant schematics too, which isn’t very good I just taped my buffer probe to the 22mm that feeds the rads and covered it in insulation.

Got it... yeah that's the exact same terminal strip pinouts as the older invertech units, with the exception that the invertech has an internal pump already wired in. It should 'just work'...

Looks like the primary pump is inside the unit... What do you need an external pump for, and where did you intend to get the PWM signal from as there's no terminal for this broken out on the main PCB.

Do you have the manual for the ET-10, I can't find it on the CE website...

As I've been digesting the Vaillant schematics for someone else, attached is the one that will give you what you asked for. Arotherm plus RADS + UFH no buffer.pdf

Same here. Weather comp, nest as a glorified on/off switch

Nope, that didn’t fix it…had to swap the valve for something less rubbish….

I still stand by my ‘nah, don’t bother’ statement…