What is a non-return isolating valve?

Combination Non-Return Isolating Valves prevent the backflow of water from a water heater to the mains line. This serves the dual purpose of protecting the mains supply from contamination, and the loss of water that has already been heated.

What is a double check valve 15mm?

A double check valve has tWO check valves in close proximity (Whereas a single check valve only has one). Check valves prevent water from flowing back. So double check valves have two checks to ensure NO back flow water can pass back to the water supply.

What is the difference between check valve and non-return valve?

A check valve is the simplest type of directional control valve used in hydraulic systems. Check valves stop the flow of fluid in one direction and allow free flow in the opposite direction. They are also known as non-return valves.

Where are non return valves used?

Non-return valves are for example used with mixing loops in heating and cooling systems to ensure proper operation, and with domestic water systems to prevent backflow.

Can a non-return valve fail?

In short, the non-return valve closure (during pump operation changeover), resulting in the water hammer in the pipe line, is likely to be the main root cause of the pump’s frequent failure.

Why do I need a double check valve?

Double check valves protect the water supply from the risk of backflow and back siphonage in domestic homes and commercial buildings, ultimately preventing potential contaminants getting into other parts of the system, especially drinking water.

Do double check valves restrict flow?

There are, however, three problems. One, check valves are prone to jamming in the open position, thereby becoming an uncheck valve of sorts. Two, they are prone to jamming in the closed position, preventing water flow in any direction. And three, they can restrict water flow.

Do isolation valves restrict flow?

If you are looking to fit isolation valves to outlets (not central heating), then: 1. If the outlet is on a high pressure (1 bar or greater) pressure, then you can probably get away with a normal isolation valve. The exception is for a bath filler or high volume shower, where a full bore valve would not reduce flow.

Are isolation valves compulsory?

No its not obligatory or mandatory (except as mentioned on Float Valves), BUT, when refitting a bathroom, usually with a minimum of five draw off points,(counting even basin or bath mixer valves as two separate draw offs for the purpose of this long winded reply) fitting them on the supply pipe to each, WILL allow you …

What is the purpose of a non-return valve?

A non-return valve allows a medium to flow in only one direction and is fitted to ensure that the medium flows through a pipe in the right direction, where pressure conditions may otherwise cause reversed flow.

When to use a non return and isolating valve?

The non return and isolating valve (NRI) provides two functions; an isolating and non-return function. The valve provides a non-return function if the upstream pressure is greater than the supply pressure, and the isolating function is used when servicing the water heater.

When to use the non return valve on a water heater?

The valve provides a non-return function if the upstream pressure is greater than the supply pressure, and the isolating function is used when servicing the water heater. We will gladly assist with returns and exchanges of this product in accordance with our returns and exchanges policy Shop wherever you are, whenever you want.

Where to find a NEFA 15mm brass female non return isolation valve?

Find Nefa 15mm DR Brass Female Non Return Isolation Valve at Bunnings. Visit your local store for the widest range of products. Javascript is required for this page Products Back Tools Back

Which is best check valve or isolating valve?

Combined check valve and isolating valve, ideal when installing garden taps. Add to basket for… Pegler 8028 Isolating / Check Valve 15mm is rated 3.5 out of 5 by 4 . Add to saved list… These reviews are managed by Bazaarvoice and comply with the Bazaarvoice Authenticity Policy, which is supported by anti-fraud technology and human analysis.