Electrics and gas
The immersion thermostat dial does not turn and the cylinder was not heated during the visit. What electrical test of that immersion is outstanding?
An electrical test of that immersion is still outstanding. The thermostat dial does not turn, and the cylinder was not heated during the visit, so the survey has a seized control and no demonstration that the heater works. It has not tested the circuit, the thermostat, the cut-out or the element. A home survey does not carry out an electrical inspection. The dial that will not move is a handling note, not a certificate that the immersion is dead or safe to use.
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 immersion is an electric heater in the cylinder, held by a thermostat. If the dial will not turn, you cannot set it, and you cannot tell from the knob whether the contacts inside are open, closed or failed. Leaving the cylinder unheated means the visit also lacks a simple working check. Neither gap is an electrical test. The survey did not apply instruments, did not isolate and prove the circuit, and did not identify an RCD for the heater. Those checks belong to an electrician.
Ask an electrician to test the immersion circuit and the thermostat, and keep that report apart from the home survey. Tell the solicitor the note is a dial that does not turn and a cylinder that was not heated. Do not describe the visit as an electrical certificate. Until the test is done, do not treat the heater as passed because the cylinder happens to be a modern shape.
What should you ask your surveyor?
- Did the thermostat dial fail to turn, and was the cylinder left unheated?
- What electrical test of the immersion circuit is still outstanding?
- Did you record a handling note rather than an electrical inspection?
What are the typical next steps?
- Treat an electrical test of the immersion as still outstanding.
- Ask an electrician to test the circuit and the thermostat.
- Do not read the home survey as an electrical certificate.
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 cylinder is hot from the boiler, has the immersion passed?
No. Heat from the boiler coil is a different source. The survey did not heat the cylinder with the immersion, and the thermostat dial would not turn. The electrical test of that heater is still outstanding. A warm tank does not show the element, the thermostat or the circuit. Those parts were not inspected electrically.
Can the seized dial be freed as part of the survey?
No. The survey does not repair controls, and it did not. The dial was found not to turn, and the cylinder was not heated on the visit. Forcing a stuck stat is not a test result. An electrician should deal with the control and the circuit. The report stops at the observation.