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Jas328sport

Hello good people, could do with some advice on a problem that has just arisen with the cold weather.
We had a new greenstar 30si boiler and complete new ch system fitted earlier this year and until now has all worked fine however this afternoon the system stopped working and the reset button was flashing. I phoned the manufacturers advice line and was told that it was probably the condensate pipe frozen. I then spent an hour pouring hot water over it and managed to get the system working again but it is obviously going to play up again. I tried to contact the person that installed the system but as usual just kept going straight to voicemail so am thinking this will be probably quicker to sort myself rather than get the run around off of him again.
Reading other advice on the net I have read that you should change the condensate pipe to 35mm as soon as it need to go horizontal outside whereas I have an 8 ft length of 22mm pipe running horizontally along the wall before it turns vertical again and then goes into a 35mm pipe.
Can I just lag the 22mm pipe to stop this from happening or will I need to cut out all of the outside 22mm pipe and replace it with 35mm.
Any advice appreciated as it is going off really cold at the moment and I have a young family to try and keep warm.
Many thanks.
 
21.5mm condensate pipe should be lagged if external however looks naff so as soon as it exits the external wall it should be increased to 32mm plastic waste pipe. But you can use lagging and tape the mitred corners.

Simon
 
As said you can just lag,use good quality pipe lagging,the problem with lagging outside is damage,after a few years will look taty and require doing again were as if you increase pipe size you can forget about it
And make sure you cut back the 22mm pipwork to were it enteres the larger pipe ,have been to three or four inspections this year were they have left the length of 22mm inside the newly fitted 11/4" :confused:
And if you come out of the building in 22mm and use 22mm bend into larger pipe,the 22mm bend needs lagging,great point to freeze ,never ever seen one 22mm elbow lagged in this siduation :(
Also another point to increase pipe size over lagging if it is run on ground floor ,is cats,they love to use lagging as a scratch post,ends up in shreads :eek:
 
it is best to change from 22 to 32 inside the building rather than where it exits as the horizontal 22 pipe is liable to freeze in the cavity of the wall and switch the boiler off
 
Thanks for all the advice. I will get onto it today as soon as the plumbing shop opens.
 
Leave a message for the installer that if its not rectified ASAP you will be contacting gas safe as the installation is illegal. All external pipework should be a minimum of 32mm
 
Leave a message for the installer that if its not rectified ASAP you will be contacting gas safe as the installation is illegal. All external pipework should be a minimum of 32mm

not complying with the boiler MI's is not illegal, it is not fitted properly if the 19/22mm isnt lagged outside, but i cant see GSR being too bothered as it isnt a gas safety issue, (even if it freezes it will turn the boiler off so isnt dangerous)
 
If as a result of the installation, the installation is failing, clearly action is required on the part of the installer.

He needs to look at bldg regs and the Assessment Procedure for Condensing Boiler in Dwellings, produced by the BRE and published by the office of the deputy p.m. which he should know.

heres the bit for you: "a minimum nominal diameter of 22mm should be used when run internally in a dwelling and a larger diameter is recommended for externally run pipe to reduce the risk of freezing (at least 32mm nominal diameter)." full doc here

also see BS 6798:2000 (condensate disposal).

there we go.
 
Hi, I have stumbled across this forum and thread as weirdly I have exactly the same problem with my Greenstar 30si and it happened last night. My question is can I cut the condensate pipe under the boiler where it comes out as a temporary measure and place a container underneath it to catch the waste water until I get the chance to replace/re-route the piping as mine is only thin too and it is not lagged. Any help would be greatly appreciated.
 
Yes, as it would be classed as works in progress
make sure big enough and checked,this time of year with heating on, a lot more condenstate will be produced ,so make sure emptied often enough
And when you say until you get round to it,I hope you mean days not years :)
empty down drain and in therory container/bucket should be plastic as condensate corrosive however do not think it will corrode through a metal container within a few days :D
 
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Thanks for your help, I mean days not years don't worry!! I'll sort it next weekend. Thanks again my girlfriend will be relieved at having hot water again!!
 
Quick update. Rang and left another message for the installer and he still hasn't bothered getting back to me although I guess it is possible that he is away.
Waking up yesterday with no heating was no fun I can assure you, the thermostat was Reading 12 degrees and I am sure that upstairs was even colder, no fun at all when all the family are unwell.
I could not defrost the pipework by pouring hot water over it so in desperation I cut the pipe only for water to gush out all over me, at least that proved that it was a blockage causing the fault though. Once the pipe was removed it was easy to unblock by pouring hot water down it, then reconnect with a push fitting and lag the whole thing properly. Central heating now purring like a kitten.
Thanks again for all the advice as this is never something I would normally have attempted myself but I am glad I did.
 
Yes, as it would be classed as works in progress
make sure big enough and checked,this time of year with heating on, a lot more condenstate will be produced ,so make sure emptied often enough
And when you say until you get round to it,I hope you mean days not years :)
empty down drain and in therory container/bucket should be plastic as condensate corrosive however do not think it will corrode through a metal container within a few days :D
I did this as a temporary measure to get the heating back on for a customer the last big freeze we had, all they hadf was an old pan which was coverd in burnt on carbonised food, 2 days later when i went back for a proper repair the condensate water had didolved the burnt on grease and cleaned up the pan like new!.
 
Well it would appear that my troubles are far from over. Heating packed up again today and when I removed my lagged pipework to defrost it again I discovered that it was clear, it is actually the larger 35mm pipe that has frozen solid right the way through. That isn't supposed to happen is it.
What can I do now because I had planned to replace all of the pipework for 35mm when it warmed up a bit but no point if it still freezes. I am currently just letting the water drip into a bucket but obviously can't leave it like that for long, am I going to have to lag the 35mm pipe as well because that will be perfect for all the cats as it runs along the ground.
 
I have had the same problem with a freezing condesate pipe.The previous owners installed a Greenstar 24i in the loft,this is coming down to the kitchen in the future,anyway looking again at the set-up about 5 ft to the right of the boiler is the soil stack!!!! The condensate pipe is going in it hence removing any external problems .Have another look where your boiler is sited,maybe there is potential for keeping the condensate pipe internal as far as possible.
 
Chris
I have a Greenstar 30si and have been very happy with it until this freezing weather when the 1 1/4 in pipe outside my garage wall has frozen solid 3 times. I removed the pipe and just let the 22 mili pipe stick through the wall but this ended up as a 1 foot long icicle. I have disconnected the condensate at the point it runs through my garage wall under the boiler and let it drop into a bucket. I will sort it permanently when the weather warms up.
 
Leave a message for the installer that if its not rectified ASAP you will be contacting gas safe as the installation is illegal. All external pipework should be a minimum of 32mm

it it not fitted as per MI hardly illegal, and if it went to court (like that is possible, he will say he lagged it and a big boy must have pinched it) and threatening the installer in such an agressive way is not very likely to get the guy back to attend to it
 
OK, water freezes if it gets cold enough. Problem is that a condensing boiler is producing a small nearly steady trickle of condensate which can cool enough it freezes if running along a cold length of pipe. If the pipe is larger or insulated it will just take longer to freeze. If it has to run outside for some distance a heating tape (self limiting heating are available from electrical wholesalers) on the pipe inside the insulation will solve the issue. If this can be damaged run the pipe with its tape and insulation in a larger pipe for protection. If using heating tape just make sure a switch to isolate / turn it off when not needed is included.


A condensate pump may also solve the issue as it waits and pumps a larger flow quicker which defrosts as it flows.
 
We seem to be getting a lot of problems here with freezing condensates, particularly with WB boilers (maybe as they are probably the most popular boilers)
I thought most condensate drains were now siphonic, letting go about 100ml at a time. Are there still condensing boilers available that let the condensate out in a constant trickle ?
 
In this weather 100ml is maybe still a bit of a small flow. A bit ends up at the end of the discharge, freezes, the next doesn't quite melt it all maybe at a slight sag in pipe or bend or coupling. Hasn't the Thames been known to freeze :)
 
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