Electrics and gas
An unvented cylinder is in a bedroom cupboard. What discharge route and service record are missing if the survey only says the cylinder is present?
The missing pieces are the discharge route and a service record. The survey only says an unvented cylinder is present in a bedroom cupboard, so it has not traced where water would go if a safety valve opened, and it has not seen papers showing the cylinder has been serviced. Presence is a location note. It is not a check of the tundish, the pipe run, the valves or the last service. The visit has not decided that this cupboard installation is in order.
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?
An unvented cylinder stores hot water under pressure. The discharge route is the path that should carry water away if a control lifts. Seeing a cylinder in a cupboard does not show where that path ends, whether a tundish is visible, or whether the pipe is complete. A bedroom location is part of the description. It is not, by itself, a verdict on the installation. The survey did not operate the valves and did not measure temperature or pressure.
Ask the seller for the commissioning and service record, and ask your solicitor to put that request with the papers. An engineer who works on unvented cylinders can inspect the discharge route as a separate instruction. Do not ask the home survey to be reread until it becomes that service. It only recorded that the cylinder is there. Both gaps remain.
What should you ask your surveyor?
- Did you see a discharge pipe and a tundish, or only the cylinder body?
- Where did any discharge pipe go after it left the cupboard, if you could tell?
- Was a service record shown to you, or is that paper absent?
What are the typical next steps?
- Ask the seller for the cylinder commissioning and service record.
- Treat the survey line as presence, not as a completed discharge check.
- Instruct an unvented-cylinder engineer if the route must be traced.
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
If the cupboard is dry, is the discharge route proved?
No. A dry cupboard means water was not standing there on the day. It does not trace the pipe, show the tundish or prove where water would go if a valve lifted. The survey still only has the cylinder as present.
Does a new jacket on the cylinder replace a service record?
No. A jacket is a cover. It is not a service record and it does not show the valves or the discharge route. The survey did not create those papers by noting that the cylinder is in the cupboard. A tidy jacket can still hide a missing service record.