Heat Pumps: anyone have one/thought about it?

Still no install date for me. I noticed on the proposal that Octopus were wanting to connect it all up to the spare RCD on the EV charger fuse box that they fitted back in October. This is straight off the main meter box outside via a henley block and if they did it this way then my hybrid inverter would not be able to see the heat pump at all. I can't simply move the CT clamp as its far from the inside consumer unit, plus I do not want the inverter to see the EV charger anyway.

The easiest way would just be a straight swap of the 2 way Live SPD consumer unit the PV is on for a three way and go straight out of the wall to outside. The heat pump only needs a 20A fuse and the PV fuse box comes straight off before the consumer unit. Will Octopus do it though I wonder? They're sending someone to take a look at it all next week.
 
They should, it’s standard for them to install a new board on installs, using an existing is the exception.

Edit: Make sure when they do it, they install a second Henley block on the ‘correct’ side of the EV charger otherwise you’ll still have problems. There needs to be enough space between the Henley blocks to get your CT on.
 
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Ron-ski said:
How did you get that done, random audit or did you arrange it - looks like I'll be using a Vaillant approved installer.

Don't suppose your in the Kent area?
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In Bristol. It was a random selection by Vaillant from the customer list of the approved installer. I knew the installer was good anyhow, but it was a nice validation.
 
b0rn2sk8 said:
They should, it’s standard for them to install a new board on installs, using an existing is the exception.

Edit: Make sure when they do it, they install a second Henley block on the ‘correct’ side of the EV charger otherwise you’ll still have problems. There needs to be enough space between the Henley blocks to get your CT on.
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Yes, this is essentially how it is already.

There's a henley block straight after the meter which splits the supply to EV charger and the rest of the house, followed by a second which splits off before the consumer unit to the PV. It had to be done this way as the consumer unit was full when I got got my solar installed. The hybrid inverter CT clamp is on the line before the henley block, so it can see the house load from the consumer unit.

Essentially all they need to do is replace the mini consumer unit (2 RCDs in it, one supplying the hybrid inverter, the other the solar only inverter) with a 3 RCD version and the third RCD can feed the heat pump. That way nothing else will need to be changed and the CT clamp see the heat pump draw.
 
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They’ll install SPDs as well which is a bonus if you don’t have them already.

Edit: my installation is already covered by SPDs thanks to my GivEnergy gateway but they added some more anyway…
 
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b0rn2sk8 said:
They’ll install SPDs as well which is a bonus if you don’t have them already.

Edit: my installation is already covered by SPDs thanks to my GivEnergy gateway but they added some more anyway…
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Yes, the current mini-consumer unit feeding the inverters has SPDs too.
 
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Ready to fall off your chairs!!!




Vaillant aroTherm 7kW with uniTower: Materials £9400, labour £6300, less BUS Grant = total of £8,200
Kronoterm 9kW system: Materials £11,600, labour £6300, less BUS Grant = total of £10,400

I would also responsible for installing the base for the heat pump

Somehow I don't think they will be installing my heat pump.
 
Ron-ski said:
Ready to fall off your chairs!!!




Vaillant aroTherm 7kW with uniTower: Materials £9400, labour £6300, less BUS Grant = total of £8,200
Kronoterm 9kW system: Materials £11,600, labour £6300, less BUS Grant = total of £10,400

I would also responsible for installing the base for the heat pump

Somehow I don't think they will be installing my heat pump.
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Some of these quotes are wild!

I managed to get BG to price match a stroppy local who quoted a system for 10,300 -> 2,800 after grant -> 800 after mortgage cash back, hopefully get a few quid back for all the old kit.

It’s been installed over the last week and they have done a very neat job.

They did however stick a buffer in the loft that I’ll have to look at getting bypassed in time.

Not having bottomless water will take getting used to though…
 
stuman said:
They did however stick a buffer in the loft that I’ll have to look at getting bypassed in time.
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Buffer or volumiser?

Buffer = 4 pipes - 2 to heat pump and 2 to the house with a pump.
Volumiser = 2 pipes, 1 in one out.

If the latter, don't bypass this, it doesn't impact performance, it aids it. It is purely their to add water volume to the system and helps when the heat pumps needs to undertake a defrost cycle. If it wasn't there, you may not have enough warm water in the system to fully defrost the heat pump and you end up in a defrost death cycle where the system radiator loop gets colder and colder each time it frosts up.
 
b0rn2sk8 said:
Buffer or volumiser?

Buffer = 4 pipes - 2 to heat pump and 2 to the house with a pump.
Volumiser = 2 pipes, 1 in one out.

If the latter, don't bypass this, it doesn't impact performance, it aids it. It is purely their to add water volume to the system and helps when the heat pumps needs to undertake a defrost cycle. If it wasn't there, you may not have enough warm water in the system to fully defrost the heat pump and you end up in a defrost death cycle where the system radiator loop gets colder and colder each time it frosts up.
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It’s a buffer, 4 pipes, Heatpump to buffer and the a pumped circuit around the house.

I already have a pump bypass pipe - just need to know if the integrated pump is enough to drive the whole loop: 15m primaries and has to lift 6m height - before I go re-routing the buffer to be volume. Or if I can do away with the tank altogether - plenty of system volume…

The system design guy did say they would do it as volume.
 
b0rn2sk8 said:
Insane, how did they get to those numbers for such a straight forward install?

Just get Octopus to slap you a Dainkin in :p
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It's crazy, no radiator changes, and a pretty straightforward install, it would likely be cheaper to do it myself.

I've got the other company coming in the morning, I'll see what they come up with.

At this rate I might have to try BG and Octopus.
 
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I wonder how they work it out? Mine is a tight cylinder install into a cupboard, 8 radiator changes, a long pipe and wire run and a 6kW Daikin and its £600 after the grant!
 
I think my house must have some sort of marker, which says Ronski lives here, charge four times as much :rolleyes: I'm not in a posh area, and it's not London, it is a five bed detached house though.

I've just had SGS Energy round, and he's going to do a new quote, so let's see what that comes back at, their indicative quote was just over £5k after the grant.
 
Octopus just use an algorithm. 5 beds anything older than a new build is probably going to be at the high end of what they quote as they are just making many assumptions.

Octopus are also pretty limited on what they install and IMO their cosy units are totally wrong aesthetically and the daikin units they use are simply some of the most ugly heat pumps around.
 
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