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Megaflo & Unvented Cylinders

What is an Unvented Cylinder or Megaflo System?

Do you want to have high pressure hot water coming from your taps and showers? Then you need to get an unvented cylinder. Megaflo is the leading brand of unvented cylinder. An unvented cylinder looks different to a normal cylinder. They are usually larger and white in colour (as opposed to bronze coloured). Also, you will need a specialist trained fitter to install them.

Megaflo Installation Costs

The cost of installing a Megaflo is different with every job. It depends on proximity to an external wall (for safety discharge outlet), proximity to electrics and size and location of the mains water pipe in the house. My Plumber will carry out a full survey to provide you with an estimate of how much the work will cost.

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Where can an Unvented Cylinder be installed?

You can have your unvented cylinder or Megaflo fitted in most locations including: loft, garage, large airing cupboard or a basement.

Does my Megaflo or Unvented System need to be serviced?

Yes, it is highly recommended that you have your Megaflo or unvented cylinder serviced annually. This typically involves cleaning filters, checking and testing the safety components, valves and thermostats. We also check the thermostat wiring and general performance of the overall system. For the annual service we currently charge a fixed price of £89+VAT (plus parts, if required).

Inlet Pressures for Unvented Cylinder or Megaflo systems operate?

Inlet pressures usually range from 1.5 bar to 3.5 bar. There is a safety mechanism fitted to ensure the maximum is not exceeded.

Installation of an Unvented Cylinder or Megaflo system

Unvented hot water systems should only be installed and serviced by a qualified and competent person holding a current G3 Unvented Qualification. All our engineers who work on unvented systems hold this qualification. It is extremely important that the system is correctly installed, together with all essential safety controls. Building Regulations require all installations of unvented hot water cylinders to be notified to Building Control. My Plumber can take care of this for you when we install your unvented system.

Is my mains water supply suitable?

It is really important that your mains water pressure, at peak times, is a minimum of 1.5 bar dynamic pressure, although all unvented systems will operate at pressures as low as 1 bar dynamic. The size of the incoming main ideally needs to be at least 25mm MDPE or 22mm copper, in order to provide adequate flow.


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