Vaillant air source heat pump installation in Congleton, Cheshire

Vaillant Arotherm Plus 7KW

Back in May 2025 we installed this Vaillant arotherm plus 7kw air source heat pump into a 1970's detached property in Congleton, Cheshire. Now this customer had done their homework.....

We were one of three companies to present a proposal to this customer and we were the lucky ones to receive the order. We applied for the £7500 Boiler Upgrade scheme funding and the voucher followed a few days later, the installation could now get underway.

After spending approximately 3 hours carrying out a detailed site survey using our amazing design software 'Spruce', we were able to determine the heat loss of the property. It came in at 6.77 kilowatts at an outside temperature of -3 and a flow temperature of 43 degree's whilst maintaining an internal temperature of 21 degree's. The Vaillant Arotherm plus 7kw was the perfect candidate for this application...

Now even though it's labelled as a 7kw, this heat pump actually outputs more than 8 kilowatts at those outside temperatures, this means that even below -3 degrees we still have additional output to use for those unusually cold winter days.

Using the building regulations calculation method (45 litres of hot water per bedroom or occupant) we chose a 250ltr Vaillant Unistor Hot water cylinder. This was to supply a main bathroom with a mixer shower and bath tub along with all the other hot water outlets in the property. We generally aim to store the hot water at 50 degrees, but since installing the customer has decided to store the water at 48 degrees as they found it to be the perfect temperature for them, this reduces the energy consumed and the load on the heat pump. On another note, this heat pump is actually capable of producing 75 degrees of hot water due to the refrigerant that is uses (R290) So should you wish to store water at 55-60 degree's like a gas boiler, you can do so. Just be prepared to pay higher energy bills.

As a part of this Vaillant air source heat pump installation we changed 8 of the 10 Existing radiators (some for heat requirements, others for aesthetics) Which allows us to run the lower flow temperature from the heat pump system. Here's a simple rule to follow, the lower the flow temperature, the lower the running costs and the higher the efficiency. That being said, it's not always the most cost effective option to replace all the radiators to gain efficiency. We will advise what that would be based on our design proposal. The new radiators that were installed were a mix of double and single panel radiators with horizontal and vertical options.

Now for the installation...

As far as heat pump installations go, it was relatively straight forward. We had the usual 'old pipework' issues which is to be expected in a property of this age, but they were easily overcome. The external pipework was run up the side of the property and encased in a suitable trunking, the pipework was insulated in that trunking with a 19mm wall Armaflex type to ensure minimal heat loss. It's not the most aesthetically pleasing look, but it was much better than removing plasterboard and creating ugly boxing internally.

The pipework was routed into the loft space and dropped down to the airing cupboard where the cylinder was located. Now this was possibly one of the smallest airing cupboards we have installed a heat pump system into, but with a little forward thinking and perseverance, we got there. Yes, it's not our prettiest installation in terms of how it looks in the cupboard, but sometimes we have to sacrifice looks for function. Fundamentally the system is there to work and be efficient at keeping your house warm. As part of this installation we also installed a 3rd party heat meter which allows us to accurately monitor how the system is performing, what heat is being produced and is the the house up to the required temperature. You can also view this data by clicking on this link https://heatpumpmonitor.org/dashboard?id=698

Here is a photo of the cylinder cupboard part way through the installation showing the heat meter.

Lastly, we commission the system. This generally takes a whole day as we flush the system, check the water quality, balance the radiators and underfloor heating, instaall all the pipe insulation and carry out the required checks on the heat pump itself. This system was actually pretty clean, we flushed for a few hours, checked the water quality and dosed with inhibitor to a required level. The system was also designed to be a direct partially open loop system (some TRV's still present), this helps negate the need for any buffer tanks or volumizers whilst increasing the efficiency of the heat pump.

If you are looking to start your journey to install a heat pump at your property in Cheshire, Shropshire and Staffordshire, please reach out to us on the below contact form link. We provide free of charge advice and will help you determine the right option for you.

https://www.altereco-renewables.co.uk/contact