HughF

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

I wasn't going to go down that rabbit hole, but I agree with you. Me, engineer - I design PCBs, write firmware, design enclosures, design wiring harnesses. Others in my company, fitters - they assemble the product. I only used the term as it's the preferred vernacular in industry (for better or worse). Interesting, the LG book shows a buffer and then an LLH after the buffer 😁

The engineers who are specifying buffers and new cylinders are just copying install schematics out of the big Vaillant book. They’re not doing anything particularly wrong, its just the options in the book aren’t very good for the UK where we have to chase the SCOP to get a system that’s on par with gas.

Yes they should be insulated… I hate flexis personally, don’t think they’re really needed if you’ve got properly bonded insulated twin… This has since had a couple of coats of the condensate pro UV touch up paint.

OK, update… Resetting the settings inside ‘tank setting 1’ to defaults of 5 and 55 has resulted in a DHW recharge. Is this ‘min temp’ value subtracted from the setpoint to give the restart temperature? Onto scheduling… do I need to specify an off period between my on periods?

I’ve been commissioning an LG gen4 and I’m after some help from the forum when it comes to DHW settings and scheduling. We’re on software 3.06.9, if that makes any difference. I’d welcome clarification on the following: Tank setting 1 -> ‘min temp’: is this the hysteresis for restart, or is this the minimum temp that the user can set the DHW to? Tank setting 1 -> ‘Comp. Limit temp’: is this the maximum LWT allowed when in DHW mode, irrespective of deltaT and or target tank temp? ‘DHW set temp’: I assume this defines the allowed values for the user when changing the DHW setpoint? Basically the issue is, we’re not getting a DHW recharge cycle even though the tank temp has dropped to something I’d expect it to restart at. Setpoint is 53deg and even at 34deg we weren’t getting a restart.

OSB is more rigid, more uniform and holds up better if it gets wet. It’s a superior product.

Aircon guy is probably better value for money too. Used to dealing with a product that isn’t marked up because of the current grant of the week.

Yep, I use flap types for this task with the flap falling down under gravity.

Remember, the LG doesn’t have a dedicated buffer sensor, it just uses an internal temp sensor in the outdoor unit to sense flow. Same as the Samsung. On an LG there’s no way to separate the two sides of a buffer system from a call-for-heat perspective (unless you’ve done a terrible job installing it) - the 3rd party room thermostat wires back to the outdoor unit. They’re literally designed to have a room stat by default. Good heat pump, complex and can do lots of things. But a good unit. p.s. On the gen4 there isn’t a heater in the outdoor unit.

To be fair my system is very simple/small. 2 rads downstairs, three upstairs (usually off), three fan coils and a ufh loop.

My eahp has anodes (it’s a glass lined/enamelled steel thing)….. I should check the service schedule on them as I’m on acidic water (it eats non dzr resistant fittings)….

Ouch…. 60 degree rads - that’s burn your skin territory.

I run all mine wide open on the valves and the lock shields, weather comp takes care of everything. Stat is never satisfied and just calls for heat from September till April. dT of about 3 degrees, but I’m on a heat pump

Modulating pump in the boiler? If so just leave them all wide open and let the pump do its thing…. Throttling the rads down will just increase pumping resistance.

Rads sized for 45@-3, ufh runs at about 30. Ivar unimix3, no buffer, CCTs for separation. Peefectly happy with the system efficiency and performance, house runs 23.5-24 all winter. Size for 45 at target outdoor temp and go from there. Do be sure to ask your significant other if 21 is acceptable design temp, I didn’t 😂

I’ve installed 2x r290 mini splits with a third one about to go in. Dead easy (but I’ve watched a lot of YouTube)

I’ve got one running with no pipe extensions and one running with a extension kit. Running on the supplied charge, haven’t changed it. No issues with either of them.