Drainage/condensation overflow pipes (posts merged into one thread)

21 Feb 2018
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United Kingdom
Can the 2 overflow pipes from the boiler, possibly condensation. 1 used to release water in to open air and the other was fed in to downpipe to drain. Both are letting out quite a lot of water. Is this a concern or normal? Also as downpipe and outside drain now gone, can these pipes be fed in to washing machine waste pipe? Please
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Who ever does the work will carry out the alterations to the latest standards and leave paperwork saying what they did :idea:

kind of doubt without seeing your installation if your idea holds water :)

Photos help :mrgreen:


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The white one is condensate and should release water and go into a suitable drain, preferably internally.
The copper one is your pressure relief and shouldn't release any washe. What is the pressure on the system on the pressure guage? Are you having to top up using the filing loop? Is the loop letting water through when it's off?
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The copper pipe does release water. The pressure gauge reads 1.2 on the red hand and .6 on the black hand. I don’t do any topping up. Or fiddling
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The two pipes are probably:

Pressure relief (normally a copper pipe turned back to the wall) - if water is coming out of this then you have a problem with your system which needs to be checked out

Condensate discharge - this should be discharging into a drain (it can be connected to an internal waste pipe but this needs to be done correctly as it is technically possible for combustion products to discharge)

Is normal for the condense to be running but NOT normal for the Pressure relief
The pressure is a little low but doesn't suggest water is getting in. Are the topstof the upstairs rads warm? Maybe the water has only the weight above it left and the pressure relief is letting by
Thanks John D the rads upstairs are always requiring bleeding as rad is hot on lower 1/3. So much do that a new bleeder is now required as worn so difficult over 5 years.
Do they bleed successfully until water comes out? Maybe you need to top up the water. Have you ever done that? Braided filing loop turn on both taps until the pressure goes up to 1bar or so.
Is the correct pressure from 1 bar to what? Rad difficult to bleed in the top room as bleed screw now worn. Have tried unsuccessfully for someone to drain rad to change it! More concerned at mo re dripping condensation relief pipe and pressure relief pipe. The boiler/tank room is directly above room with wash machine. Any other suggestions?
Correct pressure is system dependent but if you go for 1bar in a normal house should be ok.
3 storeys might need slightly more if it's downstairs.

You never mentioned whether water comes out when you bleed or just air.

The condensate drain pipe is not a relief and should be fed into a drain. A washing machine trap would be fine. Just make sure there's an air gap at some point.
Pressure relief can't be fed directly into a drain due to the potential temperature. Someone will be along to confirm whether you can run it via a tundish. You can extend it down to bnea the ground if you keep it running downfall all the way

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