Vented Hot Water Cylinder Replacement

What a vented hot water cylinder replacement includes

A vented cylinder is usually fed from a cold water storage tank in the loft, with an open vent pipe and separate hot water storage cylinder. Replacement is planned to minimise downtime and leave you with reliable hot water and confident system operation.

• Isolation, controlled draining and safe disconnection of the existing cylinder
• Removal of the old cylinder (where access allows) and preparation of the installation area
• Supply and installation of a like-for-like vented hot water cylinder, sized to suit your property and usage
• Connection to existing hot water draw-off, cold feed, vent, and primary coil pipework (where applicable)
• Replacement or reconnection of key components such as immersion heater, thermostat, cylinder stat and associated valves (as required)
• Checks of the cold feed and vent arrangement to reduce air locks, poor flow and noisy operation
• Refill, venting and commissioning, with leak checks and functional testing on both boiler and immersion (if fitted)
• Temperature and control set-up, plus handover guidance on safe operation
• Clear summary of what was done and what was replaced

When this service is the right fit

This is most relevant if you notice any of the following:

• Water marks, damp patches or active leaks around the cylinder base or fittings
• Rust staining, pinhole leaks, or a cylinder that is reaching the end of its life
• Hot water running out faster than usual, or taking too long to recover
• Frequent immersion or thermostat faults, or overheating and discharge issues
• A planned upgrade as part of bathroom work, rental compliance, or general reliability improvements

If your system is unvented (sealed and mains-fed), the approach and requirements are different. A site visit can confirm what you have and the best replacement route.

How the replacement is delivered

Work is typically completed in a single visit, depending on access, condition of existing pipework, and whether any associated parts need updating.

1. Assessment and confirmation: cylinder type, size, pipework layout, and heat sources are checked before work starts.
2. Isolation and draining: the hot water cylinder is drained safely to protect the property and minimise mess.
3. Changeover: the old cylinder is disconnected and removed, then the new unit is positioned and connected.
4. Refill and commissioning: the system is refilled, vented, brought up to temperature and tested for correct control and safe operation.
5. Handover: you are shown what has been changed and how to operate the controls and immersion safely.

After installation

You should have stable hot water temperature, improved reliability, and fewer recurring faults. If any follow-up adjustments are needed (for example, improving venting or addressing a pre-existing valve issue), these can be scheduled with clear next steps and costs agreed in advance.