How Does Mains Water Pressure Affect My Combi Boiler?

Have you ever wondered what effect your mains water pressure has on a combi boiler? It matters a lot more than you might think, as your boiler’s ability boiler to produce a steady stream of hot water depends on it being fed at sufficient pressure.

How does mains water pressure affect my combi boiler?

For a cold-mains-fed combi-boiler, it is important to make sure either before or at the time of installation that your pressure at the water main is enough to deliver an adequate amount of water to it. This should be measured by your gas Safe registered heating engineer while other cold outlets are being used (for example while flushing the toilet, filling the washing machine or running two or more cold taps). If the pressure at the water main is insufficient, the boiler may end up starved of cold water when multiple outlets are being used simultaneously. This can be minimised or remedied by your heating installer by giving the boiler more priority than the other outlets, which will be done by connecting it as the first feed from the mains.

What affects boiler performance?

The performance of mains fed hot water systems is dependent on the mains supply to your home being able to supply water at a suitable pressure and flow rate. The flow rate has to be sufficient to supply both hot and cold water simultaneously. While there may be sufficient pressure, flow rate is dependent on the incoming main too. Pressure and flow are different things, and the dynamic pressure is always less than static water pressure.

L&W Heating and Plumbing

For more information or advice, we recommend LW Heating and Plumbing. Call your local office on one of the regional numbers:-

Boiler Servicing Wigan 01942 417220
Boiler Servicing St Helens 01744 776140
Boiler Servicing Newton Le Willows 01925 394260
Boiler Servicing Warrington 01925 394260
Boiler Servicing Runcorn 01925 394260
Boiler Servicing Widnes 01925 394260