Water Pressure Guide

To ensure you achieve the best possible performance from your chosen product, you need to be able to identify your existing plumbing system and therefore your water pressure.

The following information provides a general overview on water pressures and a guide to ensure you choose the right product for you and your home.

If you have 'LOW WATER PRESSURE' you should take care to choose a product that is suitable, otherwise you might find that the flow rate is poor. It will be difficult to achieve a mixed temperature.

If you have 'HIGH WATER PRESSURE' you can choose any product with the same or lower pressure requirement.

As a general guide only, when connecting multiple products you should work to the product with the highest pressure rating.

Throughout our website we have highlighted by each product, a simple key outlining whether the product is low pressure (LP), medium pressure (MP) or high pressure (HP) along with stating the minimum pressure required to achieve the best result. The following diagram explains the pressure required for each level.

Please note all products marked LP and MP are also suitable for HP water systems.

A GUIDE TO DIFFERENT TYPES OF WATER SYSTEMS

Below outlines the four most commonly found water systems in the UK

GRAVITY FED CYLINDER - VENTED SYSTEM
Most commonly found in older UK housing Hot and cold pressures are typically unbalanced (the cold water pressure is higher than the hot) Cold water pressure is as per incoming mains Hot water pressure (head pressure) is distance ‘a’ in metres divided by 10. For examples if 'a' is 1 metre then the hot water pressure is approximately 0.1 bar This type of system is generally considered as low pressure
PUMPED GRAVITY FED CYLINDER - VENTED SYSTEM
Most commonly found in older UK housing that has been modernised Hot and cold pressures are typically unbalanced (depending on the cold mains pressure and the rating of the hot water pump) Cold water pressure is as per incoming mains Hot water pressure is as per the pump rating This type of system is generally considered as high pressure
COMBINATION BOILER - UNVENTED SYSTEM
Most commonly found in newer UK houses The 'combi' boiler is generally located in the kitchen Hot and cold pressures are typically almost balanced (the cold water pressure may be marginally higher than the hot) Cold water pressure is as per incoming mains Hot water pressure is as per incoming mains but generally reduced slightly due to pressure reducing valves, filters and flow limiters This type of system is generally considered as medium - high pressure
PRESSURISED CYLINDER - UNVENTED SYSTEM
Most commonly referred to by the brand 'megaflo' The cylinder(s) can be located anywhere in the house. Hot and cold pressures are typically balanced (the hot and cold water pressures are equal) Hot and cold water pressure is typically 3 bar (as shown), otherwise the hot and cold pressure will be approximately the same as the incoming mains cold pressure This type of system is generally considered as high pressure

If you have any questions however as to if a product is suitable for your home, please do not hesitate to contact our Customer Service team and they will be happy to help. Simply call us on 01226 283434 or complete the contact us form by clicking here.