Runnning water from Worcester Bosch 30Cdi condensate pipe

2 May 2010
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United Kingdom
Our Worcester Bosch 30CDi boiler was installed in our new build home just over two years ago. The plastic condensate pipe sticks out through the brick wall to the exterior of the house, below the boiler. Until recently, we have not seen any drips from this pipe, but about two weeks ago, it started dripping quite fast when the boiler is on, and dripping slowly even when the boiler is off. Yesterday when the boiler was on, water was flowing fast from the condensate pipe. To avoid messing up the paving slabs below, it is running into a bucket, which now needs emptying very frequently!
Our plumber was employed by the builder, who is not interested. Any suggestions as to the problem please?
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Yeah, theres supposed to be condensate running from that pipe its the nature of your he boiler

However it shouldnt be running onto slabs, it should be run to a drain ideally, bit naughty that!!

Get him back because its not fitted to manufacturers instructions
No, no, no. Two things. The pipe should be running into a drain or into a soakaway. At it's most simple, a soakaway is a hole in the ground filled with limestone chippings, but there are special plastic bottles you can bury to meet all requirements very simply.

Second, there shouldn't be any noticeable condensate when the boiler is off. The way it should work is that when the burners are running, condensate is collected into an internal trap in the boiler. Periodically this will be emptied in one go. Possibly there are cheap boilers that continuously drip out the condensate (anyone?), but still only when the boiler is running.

So, a thought. Since you never noticed water before, is this actually the pressure release pipe? Shouldn't be plastic and the water would be hot. Also shouldn't be in a position to be collected in a bucket, but then neither should the condensate.
Why would the prv not be in a position to be collected by a bucket.If it is the prv you'll notice by the constant need to top up your heating via the filling loop

Worcester condensate constantly run when actually condensing.
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The dribble when the boilers not on could be due to lack of fall on the pipe work, whatever the problem its the installer that should be returning and probably wont because its not terminated correctly
Why would the prv not be in a position to be collected by a bucket.
You can argue all day about whether the MIS, regs, or anybody else actually prohibits this, but it isn't nice for something that could randomly emit scalding hot water to terminate where it might hit someone. To me, a convenient height for catching in a bucket sounds like it isn't nice.

Worcester condensate constantly run when actually condensing.
Where do you get this stuff? It doesn't and it shouldn't. Worcester claim the condensate is released in 100ml quantities. In any case, it is certainly batched up. Maybe you've seen some long horizontal condensate pipe constantly dripping, but that's not how it is supposed to work.

Just stretching my knowledge here, but aren't there much more important reasons why a condensate pipe can't just stick out randomly? Like potentially containing combustion gases? Or is that taken care of in the siphon?
Where do you get this stuff? It doesn't and it shouldn't. Worcester claim the condensate is released in 100ml quantities.

what they claim and what happens in real life are not one and the same. Being able to read about gas and heating systems doesn't make you a gas and heating expert. It just proves you can read.

Op- The boiler is clearly installed wrong. Given that this is wrong, who knows what else is. Call Gas Safe Register and complain and they should be able to send out an inspector. Was the guy even registered?
Thank you for your replies. This is definitely the condensate pipe as the water pressure is not dropping and its building up a crust around the pipe. (We had a previous leak in the system and had to top up the water often for a couple of weeks, so know its not that)
Strangely enough, yesterday when the boiler was fired up, the pipe discharged a strong flow of water and getting worried, we turned the heating etc off so that the boiler turned off. The water coninued to flow for several minutes, and then stopped completely. On switching the heating back on, the continuous drip has ceased competely. Would this have been the boiler automatically dumping the condensate reservoir?
By the way, the boiler has been serviced annually - last time by Npower engineers, and no-one mentioned that tha condensate pipe should be into a drain.

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