Pressure Reducing Valve
A pressure reducing valve (PRV) functions, as the name suggests, by reducing a high inlet pressure at the inlet to a safer, lower water pressure at the outlet. The benefits of PRVs are multiple, as lower water pressures can decrease the amount of damage to heating systems, appliances, and buildings. Considering water pressure in the UK can vary from 1 bar to 20 bar, it is important that any risk to plumbing and heating systems is minimised to keep buildings and people safe.
As there are no regulations on water pressure in the UK there are no regulations for specifying PRVs, however, to reduce risk of unsafe water pressure it is highly recommended to specify them not only for domestic buildings, but especially for commercial buildings, where it is not uncommon to have sudden jumps in water pressure. PRVs ensure that the flow rate of water is not only correct for its intended purpose but that there is a safe water pressure that will allow other valves, such as thermostatic mixing valves, to function correctly as well. The individual valve that should be specified will depend heavily on the type of building, the water flow rate, and whether or not it is being used on a hot or cold-water supply.
The above article is an extract of "Do not get your ABCs confused – all you need to know about TMVs, PRVs and the Tenant Valve" published in the AT journal, issue 144, Winter and written by Richard Bateman, Product Marketing Manager, RWC.
--CIAT
[edit] Related articles on Designing Buildings
- A guide to installing thermostatic mixing valves: what, why and how.
- All you need to know about TMVs, PRVs and the Tenant Valve.
- Domestic hot water.
- Mechanical, electrical and plumbing MEP.
- Ofwat.
- Pipework defects, ventilation and airflow rates.
- Pipework.
- Pressure independent control valves.
- Pressure-relief valve.
- Pumps and dewatering equipment.
- Radiator.
- Tap.
- Thermostatic mixing valve.
- Types of valve.
- Types of water.
- Valve.
- Water safety plan WSP
- Water.
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