Electrics and gas
The strainer on the heat-pump circuit was left in place. What debris, if any, is still unknown?
Any debris held inside the strainer is still unknown, because the strainer on the heat-pump circuit was left in place and was not opened. The visit did not clean the mesh, sample what it had caught, or say the basket was empty. Debris downstream of a choked mesh is also unknown, since the mesh itself was not seen. The survey records a strainer that stayed shut. It has not decided the circuit water is clear or dirty.
Last reviewed 24 October 2026. Written for buyers in England and Wales unless this answer says otherwise. No named surveyor has signed this page. It is general guidance, not a report on your house, and not legal advice.
What is the fuller explanation?
A strainer is there to catch particles before they travel the heat-pump circuit. Leaving it in place means the surveyor saw the body of the fitting, not the screen. Sludge, installation swarf or scale can sit in that screen without showing on the outside. The home survey did not test heat-pump efficiency and did not drain the circuit. Approved Document L is energy-performance guidance for building work, and this visit does not issue a building-regulations certificate for the system.
If the water quality matters, a specialist has to open or service the strainer and report what was in it. Ask the solicitor for any commissioning and service record, and keep that paper separate from this look. The Boiler Upgrade Scheme is a grant route in England and Wales toward a heat pump or biomass boiler, not in Scotland or Northern Ireland. This survey has not decided eligibility and must not be read as quoting a grant. Debris in the strainer remains uninspected.
What should you ask your surveyor?
- Was the strainer body seen, or only reported by the owner?
- What stopped the mesh being opened on this visit?
- Does the report claim the circuit was flushed or sampled?
What are the typical next steps?
- Treat the strainer contents as unknown.
- Ask for commissioning and service records.
- Do not describe the circuit as clean or as blocked.
Costs vary with the building and with who you instruct. Where this page does not cite a published figure, ask the surveyor, a relevant specialist, or your solicitor for a written quote. Do not treat a forum average as the price.
Also asked about this
Does clear water at a radiator prove the mesh is empty?
No. Water at a radiator is not a view of the strainer mesh, and the strainer was left in place. Debris can sit in the screen while a radiator still runs. The survey did not open the fitting and did not test efficiency. What the mesh holds is still unknown.
Has this visit decided a grant is available for the pump?
No. The Boiler Upgrade Scheme is a grant route in England and Wales toward a heat pump or biomass boiler, not in Scotland or Northern Ireland. The survey does not decide eligibility and has not quoted a grant figure. Leaving the strainer in place is an inspection limit. It is not an application and not a decision about funding.