AK Plumbing London
Unvented cylinder service in London
Arrange a maintenance enquiry or fault assessment for an unvented hot-water cylinder. Tell AK Plumbing the cylinder make, postcode and whether you need routine servicing, help with no hot water or investigation of a dripping tundish. We will confirm the appointment options and scope before booking.
Have your postcode and a short description ready. Confirm availability, the visit charge and any additional work before booking.
Request a cylinder service callback
Before arranging a visit
A tundish is part of the safety discharge arrangement. If water is very hot, steam is present or discharge is continuous, turn off the cylinder heat sources at their normal controls only if safe to reach. Keep clear and seek urgent professional help rather than waiting for routine maintenance. Leave the discharge route unobstructed: do not block the tundish, cap pipework or tamper with relief valves. Do not approach wet electrical equipment to switch it off.
Routine service or a fault visit?
Routine maintenance
Book against the maintenance schedule for the actual cylinder model. Megaflo recommends annual servicing; check the instructions and warranty terms for other manufacturers. Have the previous service record available and mention changes since the last visit.
No hot water or an intermittent supply
A service appointment should not be assumed to include fault repairs. Explain whether the cylinder uses an immersion heater, a boiler or another heat source, and whether the problem affects every hot tap. This helps establish the appropriate diagnostic scope.
Dripping through the tundish
Water visible through the tundish needs investigation of the cause, not simply a replacement valve based on a photograph. Expansion arrangements, controls and supply conditions can affect discharge. Do not attempt pressure adjustments yourself.
What to discuss in the service scope
Model-specific safety and expansion checks
The competent engineer should follow the manufacturer procedure for the installed model, including relevant safety devices, expansion provision and discharge route. Some cylinders use an internal air space and others an external expansion vessel; they must not be treated as identical.
Condition, controls and visible connections
Agree which operational checks, leak inspections and control checks are included. Electrical testing or component replacement may need separate work. The appointment should account for the heat source and any manufacturer-specific controls.
A useful written record
Ask for a record identifying the cylinder, date, work completed, observations and recommended remedial work. Keep it with the product instructions and warranty documents. A maintenance record is not the same as an installation compliance certificate.
How to book without surprises
Send the right information
Provide the postcode, make and model from the accessible label, approximate age, last service date and symptoms. Mention difficult cupboard access or building-management arrangements. Do not remove panels or disturb valves to take photographs.
Confirm what the charge covers
Ask about the service or diagnostic charge, VAT treatment, parts, extra labour and any return visit. If a fault is found, agree the repair scope separately. Routine maintenance cannot guarantee that every existing fault will be repaired during that appointment.
Check competence and records
Work on an unvented cylinder requires relevant competence. Ask for the credentials appropriate to the proposed work; Gas Safe registration for a boiler is not by itself proof of unvented-cylinder competence. Keep records for future maintenance and warranty enquiries.
Questions before booking
Do all unvented cylinders have a 25-year warranty?
No universal warranty applies. Product and component cover, exclusions and maintenance conditions vary by model and manufacturer. Check the documents for your cylinder.
Can servicing fix no hot water?
It may reveal the cause, but diagnosis and repair are different from routine maintenance. Describe the fault when booking so that the scope can be agreed.
Is a cylinder service a landlord gas safety check?
No. A cylinder service and a gas safety check concern different equipment and requirements. Tell the booking team which services you need and ask for each scope to be stated separately.
Should I wait for the annual service if the tundish is dripping?
Report the discharge when you notice it rather than assuming it is normal. Keep clear of hot water and do not interfere with the safety valves or discharge pipe.
Related help
Further reading: Megaflo advice on annual cylinder servicing.
Request a cylinder service callback
Tell us what is happening and where the property is. Call for current availability or send the form above to request a callback.