Washing machine drain into condensate drain from boiler

[psarinuk]

Hi

I asked this question in appliances section but they advised me to ask here for a second opinion:

I've moved the washing machine from under the sink in kitchen (dishwasher there now) to the other corner of the kitchen under the Ravenheat HE85 T condensing combi-boiler (roughly 2 metres away from boiler).

I've done both hot and cold connections and worked a power socket behind the washing machine as well now.

There is a white plastic overflow pipe (22mm?) coming from boiler that runs through the back of where the washing machine is now by the wall and all the way around the back of kitchen units and it goes into the drain pipe under the sink. (about 5 metres away). Its descending down all the way from the boiler into the drain pipe.

Would it be OK to connect the drain of washing machine to the overflow pipe (by cutting the pipe and putting a T in, then attaching the drain pipe from washing machine through a jubilee clip on another small piece of overflow pipe?

Just thinking if everything should be fine with the boiler and the washing machine pump if I do this (as planned

One advice I got from appliances section is to use a Y instead of T:

For Y, I should put the washing maching drain pipe and combi condensate drain at top of Y and both of them drain into the bottom one as 1-way (the drain from washing machine and acidic residue from boiler flow one way through vertical leg of its travel into the main drain).
Thanks in advance for your advice..

 

[JPC]

i would be say no to you..

washing machines need the full 40mm waste pipe (albeit they come from smaller diametre hose..but pumped)

CAnt you replace the 21.5mm overflow pipe from the boiler condence with 40mm and run both together in that

 

[gas4you]

You need 40mm (1 1/1/2") waste for the WM. What you are describing is back to front, ie usually the boiler condensate is run into the WM waste.

 

[garagerob]

i'd say definately not!
its a lot of if's but there is the possible risk of pumping the water from your washing m/c up through the boiler if a drain blocked.
It should be on 1 1/4" min 1 1/2" pref drain though a trap of some sort to stop any smell coming up.
plus: extra duty on the pump will reduce its life.
possible syphoning of condensate trap in boiler which could affect its performance.

 

[psarinuk]

HI

thanks for your replies. I can easily manage to replace the 21.5mm overflow pipe from the boiler and condence with 32mm and run both together in that to the main drain under the sink..
40 mm however, is a bit tight as even after drilling bigger holes, there is not much space behind a few units and the cooker.
40 mm is coming a bit tight there, should I carry on with 32 or if 40 is a must, then please let me know again!!

Cheers..

 

[gigz]

Go with 40mm, can you not take the 40mm outside to drain (you can then tee in the condense waste internally to this.

 

[powell30]

No!......32mm is not big enough to take the pumped flow from the WM....it will back up and potentially block the condense pipe from boiler and/or overflow......and that will cause a breakdown if your not careful......WM waste is the biggest cause of blockages....the powder/starch is the pipe equivalent of cholesterol.......

 

[psarinuk]

Thanks to all for your replies..

I managed (only just) to drill bigger holes behind the units yesterday and replaced the 21.5 mm overflow pipe with 40 mm one. Connected them with a T with washing maching (at top) with 21.5 mm overflow pipe to the side of the T through an adapter.

The hardest job was to get the pipes connected through push-fit couplers and elbows. Very hard to apply force to push them home under the kitchen counter inside the units.