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Unvented Cylinder Service

Your unvented hot water cylinder is a pressurised container. Just like your gas boiler, it is important to get your unvented hot water cylinder not only installed by a fully qualified certified engineer but also serviced every 12 months.

If we find any issues or potential issues, we will offer you a quote for repairs.

Call out one of our Gas Safe Registered Engineers for your annual Unvented Cylinder service.

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What to expect during your Unvented Cylinder service

Here’s what you can expect when one of our Engineers come to service your Unvented Hot Water Cylinder.

Your engineer may ask you if you have the manufacturer’s instructions to hand. If you haven’t, don’t worry, as we can get copies of it online and provide you with one to remain in the property where the appliance is located. The exact procedure we follow during your service may differ depending on your manufacturer’s instructions.

The Engineer may also ask you if you have been experiencing any issues with the system, for example: “have you noticed any leaks” or “has your water been hot enough?”

The engineer will then perform visual checks for obvious defects and to check that the unvented hot water cylinder has been installed in accordance with the manufacturer’s instructions. 

Next, the expansion system will be identified. It will either be an internal expansion vessel or an external expansion vessel. The line strainer will then be checked, cleaned and the condition of the seals will be assessed and to see if they need to be replaced.

Then we will check the operation of the safety valve, tundish drainage, interlocks with external controls and the thermostat.

After testing the above, the electrical components and housing will be checked, then will be provided with the service documentation.

Your engineer will provide you with a detailed overview of the findings and answer any questions that you may have in order to give you the peace of mind that your unvented hot water system operates efficiently and is safe.

Why it's important to get your Unvented System checked annually

Unvented water systems are safe to use if they are installed correctly and if they undergo regular maintenance by a qualified engineer. 

They have three levels of safety built-in:

  1. The thermostat that prevents the water from being heated to over 60-65 degrees.
  2. If this fails, high-level cut-outs stats operate when water reaches 80-90 degrees.
  3. If these two safety features fail a temperature relief valve operates. 

If these safety features are faulty there is a risk that the water will overheat and that pressure will build up inside the tank. This is why it is important to get an annual service. Unvented cylinders have exploded in the past due to installations not meeting manufacturer’s instructions, so having your service every 12 months will also check that it has been installed correctly.

Book your Unvented Water Heater service today

Call us today! Our expert, London-based team are waiting to take your call. If properly maintained, your unvented hot water cylinder can offer an operational lifespan of 25+ years.Call us today! Our expert, London-based team are waiting to take your call. If properly maintained, your unvented hot water cylinder can offer an operational lifespan of 25+ years.

Frequently Asked Questions

If you have any questions about the unvented cylinder service, get in touch with us!

This issue is likely to be due to a faulty immersion heater if you have a direct system type.

You MUST NOT make any attempt to work on your hot water cylinder yourself. Only engineers with the appropriate accreditations should install, repair or maintain your unvented hot water cylinder.

Call us and we will send a qualified and highly experienced engineer to your home to resolve the issue. You can call us on any day, at any time.