dpmiller

it's my perception that it's sensing the system demand more accurately, giving a bit more boost on heatup.

control on return temp is another option...

seems a bit overkill, what with insurance etc. What's wrong with a trailer?

nope, a tiny bit of flow can move heat to odd places...

have you not got a diode across the 24V coils?

isn't the choice really Openreach- Virgin- Fibrus? as they supply the infrastructure...

build it on a tray with an drain to outside?

if you can't see the aluminium, it's only a scuff. Ignore...

why can't your air-to-water cool?

regeneration discharge is pressurised yes, overflow is not...

If you try to use the velux lower flexi-flashing alone you'll end up with a gutter behind the PV panel, whereas the GSE top flashing routes the water over the top of the PV. You'd also need to replicate the velux flashing for any areas that *don't* have a velux above them?

surely being able to transport items the size of a fence panel would be useful during a self-build?

Correct. not white, silver. They're not pure black panels...

it's more about pulsations/ fluctuations. The glue/ weld may have embrittled over time too...

some washing machine valves are similar. I've seen it a couple of times over the years. What kind of supply is it on, is there a pressure vessel and is it charged OK?

It's a woodburning stove with a heat exchanger, a "boiler stove". With an opening door it can only be room sealed when it's closed... it's not a roomsealed boiler.

hmm, looks like my double post *wasn't*... BRegs do not allow an uncontroled combustion appliance in a room with an extract vent. AD L, 2012 (current for NI) states "for a solid fuel appliance – a room extract fan should not be installed in the same room. If mechanical extraction is unavoidable then seek specialist advice from a mechanical/services engineer to ensure safe operation of the appliance."

If HETAS were a bit more open and transparent then things might be a bit different... Our boiler stove is room sealed but still is in a room which only has a supply vent, and I have to MVHR commissioned to slightly pressurise the house

I'd caution that a multiphase motor on a VFD might very well be running on a reduced voltage by design

Another vote here for a TS, and it's my experience that the inefficiencies that some folk mention are somewhat overdramatic

at the end of the day this scheme is all about the recovery, it's an ASHP combi. *If* you can get the heat pump on and at full chat before the store cools too much, then for a particular maximum flow rate you've an inexhaustable supply of DHW. heck, you can do the same to have a gentle shower straight off a Willis on an vented cylinder. BTDT. But we're spoilt now, seemingly requiring massive flow rates for everything...

ventilated dry ridge kit and some soffit vents

edit: I know that's for bigger cyls but the principle appears identical from what I can see?

It's a small unvented cylinder with a massive (4 to 6m2) coil and stores just enough hot water to last until the ASHP cuts in and ramps up... https://newarkcylinders.co.uk/wp-content/uploads/2024/04/HG-Series-Specification-Installation-Booklet-V2.0-Feb-2024.pdf it's all then down to the configuration of the heat pump, getting the best deltaT and control hysteresis. Just as I have found, using a thermal store for the same application (but bigger...)

probably a plastic cap pushed over a tek-screw