Condensdate from boiler, can it go in after the trap?

[kez1]

Boiler stopped working and found condensate drain from a combi boiler capped as shown in the picture.

Can I simply join this in to the sink waste after the u-bend / trap in the indicated location?

 

[terryplumb]

When did boiler stop working ,how long has it been working correctly ?
Seems an odd thing to do to cap a boilers condensate drain ,are you sure that's the case ??

 

[kez1]

details are correct. Cap has been removed. contents flowed into bucket until empty and cap replaced.
Boiler now apparently fine.

This pipe was open under the sink and dripping down ruining the under sink cabinet because it was wet all the time.
When capped it was not understood to be the condensate until the boiler stopped working.
It was thought to be part of the sink overflow when capped.

Can it be connected as shown in the picture? Need to get this fixed

 

[terryplumb]

It would be better connected before the trap to be frank ,otherwise it would be open to drainage odours etc. Probably won't be an issue as the boiler itself should have a condensate trap.

 

[kez1]

It would be better connected before the trap to be frank ,otherwise it would be open to drainage odours etc. Probably won't be an issue as the boiler itself should have a condensate trap.

I think that is why it was not connected, because the connection was upwards, and there were not enough remaining waste ports on the side of the sink waste u-bend.

Don't think it will be an issue to connect upwards, if I can find a way to connect in there, because the amount of distance upwards is much less than the over all drop from the boiler. So it will still drain.

Other wise I will connect as I have suggested in the image, after the sink trap, because the boiler, a Viessmann 050 apparently has a condensate trap inside the boiler.

 

[kez1]

The installation and service manual shows a trap, on page 42,
under heading "Checking the condensate drain and cleaning the siphon"
It appears they call the trap a siphon. The shape is clear.

 

[terryplumb]

How long has the boiler been in use with the condensate pipe capped ? I can't help but think something odd is going on here.
Technically the condensate is something a gas engineer should be installing ,and you would be well advised to engage one to check this out.

 

[kez1]

Yup. Odd indeed, as described previously.

The condensate was left open to destroy the under sink cabinet until it was capped because it was thought, somehow, to be part of the sink overflow.

Was capped mid October. We got half a bucket of water out of it when I removed the cap earlier.

Hopefully boiler is Ok.

Opinion from registered gas engineer / plumber earliear who knows this boiler said it will be ok, as long as it has been drained and it is connected to proper drainage.

So hoping it is all good as he says.

Plan is to connect it into the waste tomorrow or day after.

 

[Madrab]

Water doesn't flow uphills so i would say it's too low down to connect into the sink appliance spigot.

I'd put in a valved tundish further up on the run and then connect to the waste below.

 

[kez1]

Water doesn't flow uphills so i would say it's too low down to connect into the sink appliance spigot.

I'd put in a valved tundish further up on the run and then connect to the waste below.

That's a great solution. That's what we will do.

I'm guessing the valved tundish will allow the end of the condensate pipe to breathe so that there is not a potential air lock between the tundish and the condensate trap in the boiler, ie works just like an open tundish but stops waste potentially coming upwards from below flooding the kitchen unit?

 

[Bod ...]

In a situation like this I like to run Condense above the trap. (Depending on what the waste runs into.) Vi'a W/M port


Condense water is destructive and acidic.

Running the pipe like this Neutralises the acidic water and may safe a costly bill.


Pipe needs to flow with gravity

 

[kez1]

In a situation like this I like to run Condense above the trap. (Depending on what the waste runs into.) Vi'a W/M port


Condense water is destructive and acidic.

Running the pipe like this Neutralises the acidic water and may safe a costly bill.


Pipe needs to flow with gravity

"Running the pipe like this Neutralises the acidic water"

- do you mean it mixes with the sink water above the sink trap and therefore neutralises the acid as it runs off?
or meaning something else ...

As the condensate pipe currently runs it may not be possible to lift the pipe up as it runs behind the kitchen sink unit and is unaccessable without ripping out the kitchen unit.

I suppose we could run another pipe, behind the kitchen sink unit by just pushing it through, behind the back of the sink higher up, and then poke through the MDF/ conti board at the back of the sink unit to connect it.

 

[Bod ...]

That's what I mean. You could disconnect the existing and use a W\M hose from a to b