Washing Machine Valves

[AWheating]

What type of washing machine valves do you normally use? with or without intergrated check valve?

the reason for the question is because i have been asked what valves we should be using on a site by the customer, and i have always been of the understanding that if the machine has intergrated back flow device you do not require a WM valve with check valve but if you can not prove if the machine has a device you need to fit a WM valve with check valve. And if its unknown what machine is to be fitted then its down to the installer to ensure a risk assessment is done and correct valve used.

does anybody know if this is incorrect or the regs have altered recently?

thanks for any replys,

Adam.

 

[Plumbstar Tom]

it does need some kinda of a back flow prevention device

So if no mention of it then a double check valve on the cold

 

[Guest123]

Definately a check valve regardless of the washing machines specs. They are becoming standard now and dont cost that much more. Use good quality washing machine hoses though as I've seen the damage caused in a friends flat after a cheap imported one burst!

 

[jase158]

I find screwfix ones cant be turned on or off when you attach the hose

 

[AWheating]

from what i have been reading this evening it seems that most modern wras listed/approved machines do not require any form of check valve fitted on the cold supply as they have a built in device and/or an air gap. If the machine can not be proved to have or does not have the required device then a double check valve must be fitted on the supply (single check WM valve is not enough) because the water in a washing machine is classed category 3.

If the washing machine hose is WRAS approved then you can get away with a WM valve without a check valve, if the hose is not a WRAS approved hose then a WM valve with a single check valve is needed because the water in the hose could be classed as category 2.

if you are not installing an appliance and just plumbing in a new supply for future use then it is the installer of the washing machine that must perform a risk assessment of the installation and ensure it meets the requirements.

this is how i understand it from what i have read. its not easy working out what is required sometimes.

 

[jase158]

wow, that is a lot to take in, glad its been cleared up now, for the price of a double check valve, I think I will just add a double check valve in case.