dpmiller

what are the two bypass controls set to? and is the hidden isolator fully open?

The ASHP will have a minimum flow requirement We've about 650m over 12 loops of very unequal lengths- from around 30 to 90m. But I've no problem getting heat to all the rooms with a Yonos Pico 25 1/6 running at under 2m. There's about 1.5l/s on the loops with the highest demand

Modern fridges do indeed have a "standby" consumption. Compressor control isn't just a capillary stat any more...

We're pretty airtight (a wee bit over 1ACH) and our hood which is rated at 600m3/hr on full will a. open the sealed, weighted, gravity flap in the duct at low speed b. depressurise the house to about 30Pa when on full. ...but the supply flows increase when it's on as fans happily freewheel and bypass. I haven't yet been able to detect reverse flow at the extract vents so at worst airflow is stalling on the extract side. I would do a fair bit of stirfry and pulling the air out of the house for ten minutes is a better option to me than the possibility of greasing up thee nearby ducts...

Might there be fire protection implications to a ventilated riser like this?

Yep, the extractor will happily overrule the MVHR for the short time it's on.

@Iceverge do you not have MVHR?

If it's so easy, can you not do it yourself?

and it won't help much if you do open it, Dave. It's a blokey in his shed making stoves to his own design and reselling some others. No website, and no mention of a manual...

Have you a copy of the full test cert for the unit, rather than just the COP quoted in the manual? It has a bit more info on when defrosts are likely, the required compressor speeds etc I've attached it just in case you don't... do you see the water pump throttling back much? I'd opine that flow through the heat exchanger (and therefore deltaT across the unit) is going to have more of an effect than fan speed. But again, look in Fan configuration to see the compressor speed and fan speed limits per ambient temp. CE-iVT9 EN14825 64.181.20.04362.01 Rev.00 TR Performance Pages.pdf

any of the "works underwater" hybrid sealants?

Having been inside a few now, I think Delonghi add "improvements" per model step-up rather than time. The infusers are all the same, the pumps are the same, the transmission is the same. But the top spec machines can have quieter grinders, silencers on the pump outlet, better temperature control etc

You'll not go far wrong with a Delonghi IMHO. We've a Perfecta for a number of years now and it does everything we need. The previous Magnifica was good but ended up having an appetite for elements. Something to watch out for is that the spout adjust enough in height for whatever cups you're using...

red, white, blue?

GB, not UK.

^ I can confirm that the stat on the Tesla heaters in our World Heat tank maxes out at around 92c

the one you linked doesn't have a timer either, just a stat ?

pricey https://cpc.farnell.com/pro-elec/pel00939-uk/2kw-convector-heater/dp/HG01003?st=convector

where is the VCL?

^same here. I've subsequently tightened up some questionable door seals

@Iceverge no I'd planned around the Heatstream, but multi coil versions were discontinued ( Although RED still use them) and I changed to a bespoke unit from World Heat.

I've reduced the pump minimum to 30% and the max to 70% but with the startup at 80 to ensure the flow switch gets triggered. I've got another pump in series with it in the house, so this lets the pump modulate down and assist in managing the deltaT and I presume overall efficiency I'm not convinced that the weather compensation makes a lot of difference tbh, the daily variance in external temps means any improvements are lost in statistical noise... On the DHW settings, what difference and overshoot do you have in User Mask? Try reducing the difference by a degree or two it should then cut in sooner as the tank cools, but for a shorter time which might miss the defrost then. You might also be able to stretch the defrost period and lose a little of it's duration, depending on your ambient conditions. @Wil are yours separate or cascaded?

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Yep, I'm using a TS on the heatpump, all seems to work well enough. But hang on a mo... That Daikin unit seems *very* familiar. Looks like someone in Germany spent a lot of time :ahem: "inspecting" a Harlequin Heatstream tank...

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