Why Annual Unvented Cylinder Servicing is Essential in Horsham & Shoreham

Hi, I'm Andrew Tyler, and I'm a local Gas Safe registered engineer based right here in Horsham. 

I run Prime Boiler Care, and we look after the heating and hot water needs for customers across the Horsham District and the Adur District, from Southwater and Billingshurst right down to the coast in Shoreham-by-Sea and Lancing.

I want to talk about something crucial that is often overlooked: the annual service of your unvented hot water cylinder.

In my opinion, getting your unvented cylinder serviced every year isn't just a recommendation—it's absolutely essential. 

Cylinders like the MegaFlo are fantastic, providing high-pressure hot water, but they are also packed with critical safety devices that must be checked annually by a qualified engineer.

The Critical Safety Checks for Your Unvented Cylinder.

When I come out to service your cylinder in Steyning, Henfield, or Pulborough, I'm focused on a number of key safety and performance checks:

• Testing Safety Devices: The cylinder has multiple safety components. I manually operate and check the functionality of both the Temperature and Pressure Relief Valves (TPRV). This ensures they would open and relieve pressure if needed. I also check the discharge pipework, called the tundish, to make sure it's clear and installed correctly, which is vital for safe operation.

• Checking the Thermal Cut-Off: I test the thermal cut-off device and ensure it's wired correctly. Critically, I check that the domestic hot water zone valve physically closes when this device activates. This is the last line of defence against overheating.

• Expansion Vessel & Pressure: For performance and safety, I check and recharge the domestic expansion vessel to the correct pre-charged pressure. On older cylinders, like some MegaFlo types, I re-establish the air bubble. I also ensure the inline strain filter is clean. A blocked filter can restrict flow, hurt performance, and even cause unwanted noise from the combination valve.

• Other Components: While I'm servicing the cylinder, it makes sense to check other connected components. I'll inspect your heating circulating pump, heating zone valves, system filling loop, automatic air vents, and any drain cocks or stop cocks for water tightness. If you rely on an immersion heater, I'll check its operation too.

Why You Shouldn't Skip Your Annual Service.

An unvented cylinder is a great, safe piece of equipment under normal circumstances. 

The danger comes when you consider the "unthinkable."

If two specific failures happen—for example, if the thermal cut-off fails to physically shut off the heating source before the water reaches boiling point, and the Temperature and Pressure Relief Valve (TPRV) is not working—you have a big problem. 

The water turns to steam, pressure builds up massively inside the cylinder, and the result could be a dangerous rupture.

Your annual service is a small price to pay for the peace of mind knowing that your hot water system in Southwick or Sompting is operating both efficiently and safely.

Book Your Unvented Cylinder Service Today.

I'm here to ensure your home in the Horsham or Adur District has safe, reliable hot water. 

If you have any concerns or would like me to come and service your cylinder, please get in touch.

Unvented Cylinder Service Pricing:

• Stand-alone Unvented Cylinder Service: £90

• When linked with a boiler service: £30 (Boiler Service is £90)

I cover: Horsham, Southwater, Storrington, Billingshurst, Steyning, Henfield, Pulborough, Shoreham-by-Sea, Lancing, Southwick, Sompting, and all surrounding areas.

Contact Andrew Tyler at Prime Boiler Care:

• Phone: 01403 814602

• Address: Suite 54, Standby Business Centre, Foundry Lane, Horsham, West Sussex, England, RH13 5PX