Electrics and gas
The brine manifold is inside a locked garage the surveyor did not enter. Which part of the ground array remains unseen?
The brine manifold and the ground array beyond it remain unseen. The manifold is inside a locked garage the surveyor did not enter, so valves, gauges and the pipes leaving toward the loops were not inspected. A ground-source system circulates brine through those buried loops. The trenches and the collectors were not exposed. The survey can say the garage was locked. It has not judged the array, has not measured efficiency and has not decided the ground loops are intact.
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?
The manifold is the header where the ground pipes gather before they run to the heat pump. If that cupboard is locked inside a garage you cannot enter, you lose the labels, the isolation valves and any sign of leaks at the joints. Everything buried in the garden stays buried. A green lawn does not show a severed loop or a short array. The heat pump indoors, if it was seen, is not the ground side. The unseen part is the manifold and the array it serves.
Approved Document L is energy-performance guidance for building work, and this visit does not issue a building-regulations certificate. 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 quotes no grant figure. Ask for the garage to be opened if the manifold must be seen. Tell a lender the ground array was not inspected. Do not describe buried loops as proved from a locked door.
What should you ask your surveyor?
- Was the brine manifold inspected, or was the garage locked?
- Do the buried ground loops remain unseen with it?
- Has efficiency of the ground array been measured?
What are the typical next steps?
- Treat the manifold and the ground array as not inspected.
- Ask for access to the garage if those pipes must be seen.
- Do not describe the buried loops as proved sound.
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
Were trenches opened to expose the ground loops?
No. No trench was dug and no loop was uncovered. The manifold that would show where those pipes go was itself inside a locked garage. The survey did not see valves or gauges and did not see collectors in the ground. The array remains unseen. Digging it up would be a different instruction, not part of this visit.
Does a locked garage still let the survey decide a grant?
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 quotes no grant figure. A locked garage is an access limit. It hides the manifold. It is not an application, and it adds nothing about whether any grant would apply.