HughF

26degree flow temp into a new build I’ve just helped commission…. 125mm concrete floor slab, pipe at 150 spacing. just an fyi.

Like that’s going to happen…. It’s getting whatever I’ve got spare in the drawer.

Thanks for the info all….

I’ll be fitting a used 5kW Arotherm soon, does anyone have a copy of the wiring diagram/instructions easily to hand? I’ve downloaded the installation manual but they don’t appear to be in there. Simple install; single zone, open loop, dhw cylinder, Vaillant controls.

Umm, set your hot water at a higher temperature? I use the heat pump to heat to 50 and the upper immersion to heat the tank to 65. High hot water consumption in this house.

TS with a sanitary coil, tank-in-tank, or PHE?

I run temp diff of 12.5 and stop temp of +4 iirc…

Swapped the 3 port round and moved the wiring to suit, B to bath, all quiet now… not compliant with BR but we’ll ignore that for now.

It should be on page 2 of the user mask settings. I run weather comp (fan mode = eco) but not for hot water and the settings in user mask take precedence.

Sorry, not in front of mine at the moment. I can upload the manual when I’m home later though.

If a heat pump doesn’t have a pwm pump, a flow sensor/switch and preferably an expansion inside it then cross it off your list. Samsung gen6 I’m looking at you. Not worth messing about with ones that need all that crap externally.

Looks like a good unit for the low heat loss users, and a good price too.

Mr GH is now consulting/working for Hisense on the hvac side, apparently. Knows his stuff.

Screwdriver pushes down on the white bit at the top, wires come out. Tool-less connector.

Interesting, I’ll check mine next time I’m on-site. Been running faultlessly for 2 years now, right about the time it’ll go wrong 😂

I’ve set the pump control to fixed dT5 for both dhw and heating, still getting the knocking on changeover. re-pressurised the expansion in the outdoor unit (the only expansion on this system), pipe work seems quite secure. Not too sure what to try next apart from adding more expansion or changing the valve. I was mistaken, it’s actually an EPH controls valve, not a Honeywell.

Nope, you can never have too much expansion. If you’ve got the space on the wall just bang a bigger one in.

Yeah, this….

“6kW” r290 unit from cool energy is now around £2k, just saying. It’s 3.5kW at -7/45 but that’s probably all you need anyway. Does weather comp. Vaillant cylinder off eBay, bucket of fittings, throw it in yourself.

I don’t get this behaviour on my CE iVT9, with the same diverter, but I’m pretty sure that stops the pump on changeover.

This is a 5kW gen4 on 3.06.9 I’ll try setting the pump to a fixed dT5, it’s set to maximum flow at the moment (we were chasing a ch14 error)….. Valve is a standard Honeywell diverter in 28mm… same as used on my Vaillant cylinder (heated by a CoolEnergy), and a Samsung I commissioned at another property.

Is there a hidden setting to stop the circ pump when the 3 port changes over? We’re getting banging noises from the primary pipework when the valve changes from dhw back to heating and I’m pretty sure it’s because the pump is still running.

Sorry, what do you mean by this post? You have a monobloc unit, there shouldn’t be anything related to refrigerant to worry about.

Yes, yes you do….. Schedules all sorted. Onto the next issue.

'Surface coating engineer' - glorified painter and decorator