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Servicing of an ASHP above a flat roof
I am trying to decide on the options for placing an AHSP as part of a new installation.
One option suggested to us is to put it on brackets on the house wall just above our flat roofed garage. The advantages of this seem to be two fold. Firstly it will be really close to the water tank and existing plumbing so will need minimal runs of extra piping so should be as efficient as possible. Secondly it'll be pretty much out of sight - we don't have a huge garden and aren't really keen on it being right there in your face when you're sitting out there.
A possible drawback the designer pointed out to us might be servicing - some engineers might not be keen to climb up a ladder onto flat roof to look at it. Is this something I should be worried about, have others run into this, or is it not really a concern ? The pump being suggested is a Valliant one.
That is precisely what we have and for the same reasons. It is true, though, some engineers/companies will not perform service work at height, so it may limit your future choices when it comes to servicing. If an installer fits it there, it would make sense for them to agree to service it.
Also be warned, though heat pumps are generally quieter, they do still emit vibrations that may annoy you when inside the house under some conditions. Ironically, we don't notice ours when it's working hard, but when the compressor is operating at low speeds, it can be felt rather than heard on that side of the house, feeling a bit like a distant idling truck. It has never caused us an issue, but it is something to consider if the location is backing onto a bedroom, for example.
1970’s 3 bed detached house in West Sussex. Mains gas disconnected September 2023.
Samsung HTQ 8kW heat pump using mostly existing radiators. House is warm 24/7 (normally between 20.3-20.6 C but currently with a newborn its 21-21.2 C).
Sunamp for hot water storage.
Solaredge 6kWp PV and 10kWh battery
Vehicle 2 Grid charger (used with a Leaf)
Wallbox EV charger (installed for Octopus Intelligent).
Home Assistant used for HEMS with lots of custom ESP devices to allow integration.
Insulation upgrades:
EPS cavity wall insulation.
Improved loft insulation (renewed and 300mm where possible).
Posted by: @stevehspA possible drawback the designer pointed out to us might be servicing - some engineers might not be keen to climb up a ladder onto flat roof to look at it. Is this something I should be worried about, have others run into this, or is it not really a concern ?
Yes, this is a valid consideration. I've heard similar concerns from both manufacturers and installers. While accessing equipment via a ladder onto a flat roof is generally safer than working directly from a ladder, it can still deter some service engineers.
Another factor to weigh is maintenance: if components need repair or replacement, the accessibility challenges might make some professionals hesitant to take on the job. It's worth discussing this with potential installers upfront to gauge their comfort level and ensure they're equipped to handle future servicing needs.
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Thanks both
It can be positioned so that it's not on a bedroom wall, and only the spare room is on that side of the house. I'd hope we'd be OK in that respect but of course we'd never be sure until it was done. Having it in the garden would probably mean being directly below a bedroom window so that's not ideal either.
I'll ask the installer about the servicing he might take on, good point. But at some stage I guess the manufacturer might need to come out. I note you say 'some' not 'all' engineers / companies might be reticent to take this on, so that's good! Perhaps it's worth contacting the relevant manufacturer before finally deciding.
@arundalep I think the access is now a major H&S issue for all companies; we recently had FTTP installed and the route had to be more circuitous than we thought it might as the installers are strictly forbidden from gaining access via flat roofs now. Toodles.
Toodles, heats his home with cold draughts and cooks food with magnets.
Posted by: @stevehspI'll ask the installer about the servicing he might take on, good point. But at some stage I guess the manufacturer might need to come out. I note you say 'some' not 'all' engineers / companies might be reticent to take this on, so that's good! Perhaps it's worth contacting the relevant manufacturer before finally deciding.
Possibly you could have movable barriers available. The principal risk I think is forgetting you are on a flat roof, stepping back and... barriers prevent this.
4kW peak of solar PV since 2011; EV and a 1930s house which has been partially renovated to improve its efficiency. 7kW Vaillant heat pump.
@jamespa We have 4 solar panels on a flat roof and the 3 sides away from that which attaches to the house had scaffolding and barriers in place before the roofers arrived. The next year they had to erect another set of scaffolding and barriers to make changes to the panel mountings as they vibrated against the micro-invertors whenever we experienced high winds. Toodles.
Toodles, heats his home with cold draughts and cooks food with magnets.
Posted by: @toodles@jamespa We have 4 solar panels on a flat roof and the 3 sides away from that which attaches to the house had scaffolding and barriers in place before the roofers arrived. The next year they had to erect another set of scaffolding and barriers to make changes to the panel mountings as they vibrated against the micro-invertors whenever we experienced high winds. Toodles.
Yes it can be a problem.
When we put our solar panels on a flat roof one very serious consideration was access to clean the windows! The window cleaner is happy.
4kW peak of solar PV since 2011; EV and a 1930s house which has been partially renovated to improve its efficiency. 7kW Vaillant heat pump.
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