Adding washing machine stand pipe to existing boiler waste.

[jmgh]

Hello,

I want to move my washing machine into the conservatory.

There is a waste pipe that takes the waste water from the boiler along the outside wall leading to the gully. Only the boiler drains into this pipe, there is a trap on the inside wall.

I’d like to extend this pipe further along the wall to the conservatory using a tee, to take the waste water from the washing machine.

Will I need a vent at the end of this pipe after the w/m standpipe?

Do you foresee any issues with the washing machine waste water backing up into the boiler trap?

Many thanks!

John

 

[terryplumb]

What is the diameter of the horizontal waste pipe ?

 

[Madrab]

If you are using a stand pipe for the appliance () then the run would be naturally vented anyway, presuming that the waste pipe is 40mm as that's the size of a standard stand pipe. (As per @terryplumb 's question) You would want the boiler condensate run into the top of the Tee.

FIY, as as standard though, it should really be a qualified bod to make changes to a boilers condensate run, just in case anything is disturbed and repairs need to be made. Wouldn't the first time I've seen a DIY'er pull the connection of the boiler condensate trap when re-doing undersink condensate pipework, luckily they had a working CO detector.

 

[jmgh]

What is the diameter of the horizontal waste pipe ?

Thanks for replying. It’s Standard 40mm waste.

 

[jmgh]

If you are using a stand pipe for the appliance () then the run would be naturally vented anyway, presuming that the waste pipe is 40mm as that's the size of a standard stand pipe. (As per @terryplumb 's question) You would want the boiler condensate run into the top of the Tee.

FIY, as as standard though, it should really be a qualified bod to make changes to a boilers condensate run, just in case anything is disturbed and repairs need to be made. Wouldn't the first time I've seen a DIY'er pull the connection of the boiler condensate trap when re-doing undersink condensate pipework, luckily they had a working CO detector.

Thanks very much for the detailed response!
My boiler man will be by in a week or so after I get some rads back on the walls so will get him to look it over then.

Out of interest, what would be the CO risk with an improperly plumbed condensate outlet? Wouldn’t it just be a case of damp cabinet problems etc?

Thanks again,

John

 

[terryplumb]

Risk is combustion products entering the property ,as it's technically part of the flue system

 

[Madrab]

Out of interest, what would be the CO risk with an improperly plumbed condensate outlet?

As suggested there is a risk that CO can be let into the living space.

That being said most boilers do have traps therefore the risk is small but in the case I mentioned, they had actually pulled the trap off of the drain pipe from the bottom of the HEX and Products Of Combustion (POC's) were leaking into the room, hence why I was called when the CO detector went off. It isn't worth the risk IMO.

 

[jmgh]

Ok, makes sense, I’ll just wait for the boiler guy to come and do the changes on that day. Thanks for your help.

 

[gas112]

is the gully for rain water or waste water ?

 

[jmgh]

is the gully for rain water or waste water ?

Its combined, we don’t have separate rain and foul water drainage on our property.