Central heating

Air source, ground source and associated systems for heating homes
jonc_uk
Posts: 59
Joined: Fri Jul 08, 2022 1:56 pm

Re: Central heating

#21

Post by jonc_uk »

I have the same problem occasionally with my Panasonic Aquarea 16kW A2W heat pump running UFH in Portugal.

It would throw either H62 - 'Water switch abnormality' indicating the flow rate is too low, or H12 - 'Indoor/Outdoor capacity unmatched'.

The H12 error is the most annoying - it basically means the unit has been unable to wind down the output capacity enough to maintain the flow temperature. It should have stopped the compressor, but these units are too clever for their own good.

I think the proper solution to all this is that there should be a buffer tank between the heat pump and the UFH. What I did was ensure there was a kitchen radiator always open in the loop, and use the low/normal/boost settings on the app which change the flow temp - 35C / 40C / 45C depending on the time of year.

When I installed a Kensa 25kW GSHP in the UK, I separated it from the UFH with an 800 litre thermal store. The Kensa units are also so simple that they are either on or off - no errors here.
Oldgreybeard
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Re: Central heating

#22

Post by Oldgreybeard »

A low loss header is a sort of mini buffer designed specifically to get around this problem, although they were originally designed for use with boilers and multiple circulation pumps. Dead simple, just a fat bit of pipe with two pipe connections at the top and two at the bottom, that's connected inline with the flow and return. This is a good article describing them: https://www.heatgeek.com/low-loss-headers/

The big advantage over a buffer tank is that they don't take up anywhere near as much space.
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Joeboy
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Re: Central heating

#23

Post by Joeboy »

House had crept down to 10 degs in.last few days so had a fair heatsoak to do. Ran most of the SH's while we were on our way home from Glasgow this morning( in front door at 03.30). It had taken the sting off but very glad to run up the WBS this morning. Big lounge where WBS lives is really nice now, over 20 degs and heat shove into rest of house ongoing. WBS storage bricks are up to temp and will keep emitting long into the night while we get the fabric back up to habited space.
Image

Image

It's pulled duty as kettle and also tumbledryer today for that no grid bonus it provides in these solar tightening months.
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Oldgreybeard
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Re: Central heating

#24

Post by Oldgreybeard »

Still no heating at all here, this is the temperature in our hall as of a few minutes ago:

Thermostat.jpg
Thermostat.jpg (44.51 KiB) Viewed 2608 times
It's still relatively mild outside, too, although getting cooler. It's 11.4°C outside at the moment, but the sky's clear and I think we'll be in for a cooler night tonight.
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Fintray
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Re: Central heating

#25

Post by Fintray »

Joeboy wrote: Thu Nov 03, 2022 4:20 pm House had crept down to 10 degs in.last few days so had a fair heatsoak to do. Ran most of the SH's while we were on our way home from Glasgow this morning( in front door at 03.30). It had taken the sting off but very glad to run up the WBS this morning. Big lounge where WBS lives is really nice now, over 20 degs and heat shove into rest of house ongoing. WBS storage bricks are up to temp and will keep emitting long into the night while we get the fabric back up to habited space.
Image

Image

It's pulled duty as kettle and also tumbledryer today for that no grid bonus it provides in these solar tightening months.
You'll be needing that extra heat into the house tonight seeing it's down to 3C already. :shock:
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Joeboy
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Re: Central heating

#26

Post by Joeboy »

Fintray wrote: Thu Nov 03, 2022 6:49 pm
Joeboy wrote: Thu Nov 03, 2022 4:20 pm House had crept down to 10 degs in.last few days so had a fair heatsoak to do. Ran most of the SH's while we were on our way home from Glasgow this morning( in front door at 03.30). It had taken the sting off but very glad to run up the WBS this morning. Big lounge where WBS lives is really nice now, over 20 degs and heat shove into rest of house ongoing. WBS storage bricks are up to temp and will keep emitting long into the night while we get the fabric back up to habited space.
Image

Image

It's pulled duty as kettle and also tumbledryer today for that no grid bonus it provides in these solar tightening months.
You'll be needing that extra heat into the house tonight seeing it's down to 3C already. :shock:
I'm in my bed! Time difference and battery install caught up. :D 3C :shock: where's my 30C went? 8-)
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Joeboy
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Re: Central heating

#27

Post by Joeboy »

Feck!

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Fintray
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Re: Central heating

#28

Post by Fintray »

Joeboy wrote: Fri Nov 04, 2022 7:38 am Feck!

Image
Better get used to it! :lol:
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10.24kWp PV SolarEdge system
Tesla Powerwall 2
100 x 47mm Navitron tubes (still being installed!) Now likely to be removed for more PV.
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Joeboy
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Re: Central heating

#29

Post by Joeboy »

Fintray wrote: Fri Nov 04, 2022 10:30 am
Joeboy wrote: Fri Nov 04, 2022 7:38 am Feck!

Image
Better get used to it! :lol:
Trying! :D
Last edited by Joeboy on Thu Nov 10, 2022 8:20 am, edited 2 times in total.
15kW PV SE, VI, HM, EN
42kWh LFPO4 storage
7kW ASHP
200ltr HWT.
73kWh HI5
Deep insulation, air leak ct'd home
WBSx2
Low energy bulbs
Veg patches & fruit trees
Oldgreybeard
Posts: 1873
Joined: Thu Sep 09, 2021 3:42 pm
Location: North East Dorset

Re: Central heating

#30

Post by Oldgreybeard »

Temperature in the house dipped down to 21.5°C last night, almost low enough for the heating to come on for the first time. However, today is bright and sunny, so we're getting a fair bit of solar gain, which I hope will delay the heating needing to come on for another day or two. Can't be far off the time when we need to run the heating overnight every now and again, though.
25 off 250W Perlight solar panels, installed 2014, with a 6kW PowerOne inverter, about 6,000kWh/year generated
6 off Pylontech US3000C batteries, with a Sofar ME3000SP inverter
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