Unvented Cylinder Installation


01277 411739




We are based in Brentwood and cover the Essex area.

Unvented Cylinder Installation Brentwood, Essex

Unvented Cylinder Installation

Looking to install an unvented cylinder? Call 07908430123/07903803066

1st Choice Heating Services is your local G3 qualified unvented cylinder installation specialist. We recommend and install Megaflo cylinders in particular, as well as other makes.

Our team have experience of over 45 years and have installed hundreds of unvented cylinders over this time.

Before installing an unvented cylinder in your home, there are a number of considerations that need to be made. We can go over these considerations with you and do not charge for the survey that is required before we install your unvented cylinder.


Unvented Cylinder Installation Brentwood, Essex 2

Considerations Before Installation

1. Where will the cylinder be fitted?
Unvented cylinders are heavy, with some weighing as much as one ton when filled with water. You will need to have a strong base for the cylinder to rest on.

2. Water Pressure
Unvented cylinders are connected directly to the cold water main.

The pressure is limited on the cylinder controls to 3bar. Your water pressure needs to be greater than 1.5 bar (preferably more than 2bar) to work correctly.

The water pressure will need to be tested at your property using a water pressure gauge; this is normally done on the outside tap.

3. Water Flow Rate
It is important to understand the relationship between pressure and flow.

Pressure difference is what causes flow to happen. In the case of an unvented cylinder, this would be the pumped water main’s pressure entering your property.

Once the pressure has been tested, the flow rate needs to be checked using a weir cup. Flow rate is important because this is effectively the amount of water that passes out of the taps.

In many properties, lead is still in use as the service pipe. Normally, these pipes weigh 7lb. The diameter of the pipe is the same as 15mm copper.

You will need to ideally upgrade the pipe to MDPE (blue plastic pipe) with a diameter of 25mm, at a minimum.

4. Pipework
Many pipes found in today’s homes require an unvented cylinder to operate correctly and safely.

The pressure relief and temperature relief pipes have to be taken away from the cylinder to the outside of the property.

Before installing an unvented cylinder, the above considerations and testing need to be thought out and completed.


1st Choice Heating Services will help you design, specify and install a new unvented cylinder.