My DIY installed Vaillant AroTherm Plus is now LIVE

championc · 17-02-2025 05:47PM

Just a quick update

My January Pinergy bill landed, and it's €140 Net after €30 FIT.

So €140 to run the house, cooking and heating, and run an EV. That's less than €5 per day 🤩

Heatpumpmonitor.org has my SCOP at 3.9 👍

championc · 10-04-2025 07:04PM

COP in the past week has been over 5 each day 😎

monseiur · 16-04-2025 08:33PM

https://www.boards.ie/discussion/comment/123181684#Comment_123181684

Hi champion, I have been lurking in the background for some time now. Your figures are very impressive, considering that your walls are cavity/hollow blocks do think that the external insulation that you plan is worth the expense ?

championc · 16-04-2025 10:10PM

https://www.boards.ie/discussion/comment/123363924#Comment_123363924

The only way it can be worth it is by doing a self install of the wrapping.

I am possibly spending less than €500 a year on electricity for heating, so I wouldn't have a hope in hell of recouping the €20k+ that it would cost to have it done by a company, over my lifetime.

Yes, the house is far more comfortable now, and will be even more so, which is just about making it worth doing myself.

Of course, the low running cost is down to my batteries and 5c Pinergy night rate power

championc · 17-09-2025 08:05AM

Insulation boards all installed, and now the rendering has started 😀

championc · 17-09-2025 08:07AM

Not hugely cold outside yet, but very encouraging signs with that COP figure

championc · 18-09-2025 02:58PM

My SCOP from 01 Nov last year has been solid on 4.20, but is now rising upwards due to the external insulation and the lower heat curve value.

championc · 02-10-2025 09:24AM

Getting there 😎

10-10-20 · 02-10-2025 10:29AM

https://www.boards.ie/discussion/comment/123869514#Comment_123869514

So that's the k-rend or coloured external coat there. How are you finding blending it in at the joins between a day's work?

championc · 02-10-2025 11:33AM

I am using Credit CT-74 for the top coat. You can't scrape it any thinner than about 1.5mm, so you only have hard edges, and so you just render one section up to the next.

championc · 06-10-2025 11:07AM

Couldn't help posting this - top of the COP chart for the past 30 days 🤩

Max Abbey · 06-10-2025 03:57PM

Awesome, well done

zakalibit · 18-10-2025 11:23AM

@championc regarding no buffer tank in your install, as I understand rads do not need to have any TRVs, neither any termostasts need to be in action, i.e. they have to be fully open? This is to ensure there is no short circuit happening, i.e. the heatpunp has always water to run around?

championc · 18-10-2025 07:49PM

Volume is needed in the system for defrost cycles. But it is also a key part of efficiency.

The efficiency comes from the system running constantly, with little or no system restarts. So then, if there was insufficient volume, that would create greater chances of the heat not being lost enough going around only a few rads.

But none of this is any excuse to install a buffer tank. If you somehow need volume, install a volumizer.

A buffer will complicate your system. The system itself has a pump, which SHOULD be able to drive the water around your whole house, provided that that pipework is correctly sized. But if you install a buffer, you then need a secondary pump, which MUST run at exactly the same speed as the units pump.

zakalibit · 18-10-2025 08:24PM

That is what I'm looking at at the moment, volumiser like install but without it, i.e. make sure rads are always open.

I'm considering https://midsummerwholesale.co.uk/buy/samsung-heat-pumps/Samsung_r290_integrated as it has a builtin expansion vessel and flow sensor, as well it comes with EHS Wifi Kit and Control Centre. So I have to buy very few extras.

Here is the schematics for the direct connection

https://midsummerwholesale.co.uk/pdfs/samsung-r290-integrated-quick-start-10-24.pdf

championc · 19-10-2025 07:58AM

Just a quick thing on the WiFi connection - what are you hoping to use that for ?

For me, apps are utterly pointless for two reasons. Firstly, once setup correctly, you shouldn't need to touch anything 365 days a year. It shuts down automatically in summer. Secondly, if you want data, you don't want to be relying on some cloud server. You want to pull data directly locally off the unit.

zakalibit · 19-10-2025 09:29AM

Fair points.

As a minimum I hope to use wifi for a lazy way to monitor the system. I did not figure out yet the data extraction from the unit. First I'm focusing on getting it installed and running, then I'll figure out the rest :) as the parts and install part is already overwhelming for me :)

I see it has HA integration, so I'll be looking at leat to integrate it with my HA.

Grassy Knoll · 19-10-2025 10:15AM

hi did you re-pipe your rads ? Fair due to you, from the bit I understood it is working well and blows narrative that ‘it has to be a modern house for HP to work’ out of the water. Fair play to you!!

championc · 19-10-2025 03:40PM

I had to re-pipe one section, which was a real pita. There was a 1/2" going from the dining room doorway to the sitting room, feeding the sitting room main rad and the hall rad.

Running at lower temperatures, I needed to add a second rad to the sitting room. This meant that there were 3 rads downstream of this 1/2", so I redid it with 3/4", as I didn't want to fall foul over something simple.

The real pita was the fact that this was under a glued laminate floor, partially inaccessible.

I'm glad I did it, as if I didn't hit the COP levels I hoped for, I would have left myself with a massive "what if".

The big advantage of self installation was that I took it up in chunks, carefully, cleaned off all joints afterwards, and was able to relay it to the point you'd never know it came up 🤩

championc · 19-10-2025 06:21PM

And if you are planning to import it from the UK, would you not have considered the AroTherm ?

zakalibit · 19-10-2025 08:36PM

https://www.boards.ie/discussion/comment/123919508#Comment_123919508

😎 no https://groupsumi.ie/climate-control/aerothermal-energy/outdoor-aerothermal-units/samsung-ehs-r290-monobloc-air-source-heat-pump-5-0-kw-ae050cxybek-eu

+ I think AroTherm is more expensive, not by a huge amount

zakalibit · 01-11-2025 02:02PM

@championc did your SensoComfort Wireless Controller came with outdoor sensor? like in this example https://www.mrcentralheating.co.uk/vaillant-sensocomfort-vrc720f-wireless-rf-multi-zone-room-thermostat

championc · 01-11-2025 02:08PM

Yes it did indeed come with the wireless sensor. I would suggest to anyone going the Vaillant route to get the WIRELESS sensoComfort

zakalibit · 01-11-2025 02:21PM

https://www.boards.ie/discussion/comment/123953581#Comment_123953581

The outside sensor wired, or solar wireless?

championc · 02-11-2025 01:08PM

Wireless with the wireless sensoComfort / wired (and possibly not included) with a wired sensoComfort.

The wireless allows anything to to placed anywhere. I just don't see the point in not going with the wireless

Scoopsire · 13-11-2025 03:27PM

https://www.boards.ie/discussion/comment/123956673#Comment_123956673

Was it hard to get a sparks for the electrical side of things…….looking into doing similar myself

great work is all i can say!

championc · 13-11-2025 06:41PM

Did it all. Basically, all I had to do was to tap into my original flow and return pipes, and then run those pipes out to where I was locating the outdoor unit.

It would have been so handy if I had had the space to put the outdoor unit backing onto the house wall where the pipes emerged, but that was the side passage, and only 1.6m between our wall and the neighbours, and that was before I was doing the insulation wrap !!

Scoopsire · 19-11-2025 08:30PM

Just saw this now, once again great work.

micks_address · 25-11-2025 03:00PM

Interesting thread. We are in a 4 bed semi which is built with hollow blocks. We replaced all the double glazing with triple glazing last year and heat loss is 1.905. I don't think i could ever justify the cost of external wrap. Because we have quite large windows back/front/patio door the gable wall is probably coldest/least windows. Im curious what kw heatpump we might need. Currently on gas boiler which has plenty of life left in it so probably not changing it any time soon. All pipework and rads have been changes in the last few years. I think they should be big enough for a heatpump. One challenge i see is our 12kva esb connection. We have storage batteries/solar & ev.. and they are pretty much maxing out the esb connection each night. I would love to get a proper survey done at some point to come up with the 'right' size heatpump. Our plumber who is sound says they normally bring the plans into heat supplier and they work out the heatpump size.. doesnt seem very scientific. Last thing i'd want is a undersized or oversized heatpump.. I suspect 5 or 6 might be what we need.

Fair play on all the work and sharing all in the thread.

Thanks,

Mick

championc · 25-11-2025 06:20PM

Do your own calculations with heatpunk.ie. Use 0.7 air changes per hour for all rooms for the most accurate calculation. The u-value for cavity hollow blocks is around 2.3. It would be interesting to see how heatpunk looks compared to your ber figure.

I think my 5kW is now perfectly sized for our house. It runs on minimum all day long.

A 4 bed should be no more than a 7kW I would have thought. I was able to run perfectly fine last year on our 5kW, but it would have run harder than minimum on those really cold days.

My DIY installed Vaillant AroTherm Plus is now LIVE

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