Ideal Optia HE12 Drain Problems

[shaky1105]

Hi, boiler as above. The condensate drain doesn't appear to be working correctly. The boiler will run for a while, then switches the gas off. After a bit of fault-finding, it appeared that the pressure switch was causing the problem. However, I noticed that the condensate syphon was absolutely full of water, therefore causing the pressure switch blockage pipe to shut the gas off.

If I blow ( gently is all that's required ) down the white pipe from the pressure switch ( to the syphon ) a bit of bubbling is heard, then the syphon drains as it should and the boiler will work OK again. However, after a few hours, or days or even a week it will do this again. The external drain pipe is all perfectly clear and not freezing or anything like that, it's just the syphon that appears to be intermittently not working.

I've looked at the breakdown pictures of the boiler and the syphon isn't too difficult to get at so as the boiler was fitted quite a while ago ( now out of warranty ) I was wondering if replacing/repairing this part is something that I would be allowed to do myself or do I have to call a registered person in ?

Thanks.

 

[shambolic]

Double trapped and air locking?

 

[shaky1105]

Double trapped and air locking?

Thanks for the reply shambolic but I'm not sure what you mean ? The drain pipe runs out of the boiler, makes a u-bend shape about 4" deep, ( this seems to agree with the instructions in the fitting manual the installer left ) then exits out the wall of the house and into the drain.

I've double checked the whole pipework and there were definitely NO blockages anywhere while this was happening but as soon as I blew down the white sensor pipe, the syphon.....well syphons !

It's not too bad at the moment because it hasn't happened while we were out but I don't want to come back to a house that's freezing cold if it stops while we are away anywhere and £££ is very tight, hence why I would like to know if it's OK to have a go at it myself otherwise I will restrict xmas spending so I can afford to get a pro in to do the work.

Thanks again

 

[shaky1105]

Anybody else have any ideas ? Please !

 

[plummerman]

You've answered his question my friend without knowing which probably means you shouldn't really be messing inside boilers.

B

Basically boiler has a 75mm water seal trap, the u shape you mention is basically another trap that a dafty has fitted because the pipeline joins a soil pipe. It don't need it as the boiler trap is more than deep enough to prevent smell etc coming back up the line

 

[shaky1105]

You've answered his question my friend without knowing which probably means you shouldn't really be messing inside boilers.

B

Basically boiler has a 75mm water seal trap, the u shape you mention is basically another trap that a dafty has fitted because the pipeline joins a soil pipe. It don't need it as the boiler trap is more than deep enough to prevent smell etc coming back up the line

Thanks for the reply plummerman. To be honest, I didn't really want to be fiddling inside the boiler, it's just that with money being tight at the moment and the layout diagram of the boiler looking reasonably straight-forward I would have had a go myself.

So even though the Manufacturers instructions show the u-bend in the pipework as being correct, there isn't a need for it and that is what could be causing the problem ?

The pipe is readily accessible from the inside so I could easily cut-out the u-bend part to allow the drain to flow straight, horizontally into the waste.

Thanks very much.

 

[bernardgreen]

Rather than cut out the U bend you could fit a T with a short vertically upwards open ended pipe to form an air vent between the U bend and the boiler. To be 100% sure it doesn't over flow when the boiler dumps condensate the end of the vertical should be at the same height as the syphon but the volume of the pipe work will take most of the condensate so over flowing of a lower vent is un-likely. The U bend and the boiler trap then work "independently" of each other.

Then in summer when the boiler isn't used and the internal trap dries out there is still the U bend to prevent drain smells getting into the kitchen. And if the U bend dries out it can be filled via the air vent from the T

 

[Agile]

The manufacturers expect the boiler will be used during the summer for hot water heating.

It is not recommended to have a condensate pipe vented to atmosphere indoors as if the trap did dry out then dangerous products of combustion will enter the room.

There should be no issue with disposal drain smells as the condensate pipe from the boiler only communicates with the flue which terminates outside.

What depth secondary trap do Ideal recommend and what is yours OP ?

Tony

 

[bernardgreen]

The manufacturers expect the boiler will be used during the summer for hot water heating.

Manufacturers expect a lot and in some cases do not realise their expectations do not match the user's

It is not recommended to have a condensate pipe vented to atmosphere indoors as if the trap did dry out then dangerous products of combustion will enter the room.

A valid point which I had overlooked in the plan to keep the boiler running for the OP But looking at some "manufacturer's recommendation" it seems OK by them to connect the condesate drain into a sink drain between the sink and its U trap. Is this in order to prevent the double trap problem the OP has ? In which case a dry trap will allow combustion products to escape via the sink waste pipe.

There should be no issue with disposal drain smells as the condensate pipe from the boiler only communicates with the flue which terminates outside.

Provided the drain smells do not include too much sewer gas with inflammable ( explosive ) methane

 

[shaky1105]

The manufacturers expect the boiler will be used during the summer for hot water heating.

What depth secondary trap do Ideal recommend and what is yours OP ?
Tony

Hi Tony, thanks for the reply. In the Boiler instructions, it says a minimum of 75mm. The pipe actually comes straight down out of the boiler about 9" then forms a u-bend about 4-1/2" deep before going straight through the wall and directly into the soil waste. Only about 2" of pipe is exposed outside before it enters the waste pipe.

The boiler is used for the heating only, we have a separate boiler for the water. This was recommended by the fitter as he said it would be unnecessary expense to have the old water heater ripped out.

edit: Just a thought, should I have re-filled the syphon before we started to use the boiler this winter ? Just wondered if maybe there's lime or something possibly partly blocking the syphon

 

[shambolic]

So I was right with the double trap airlocking. If the heating boiler is off all summer and trap dries out them pour some water into the inner flue outside to re prime the syphon.

 

[shambolic]

The syphon will fill itself after a couple of hours condensing but until then fumes will pass down the condense line, hence what I said above

 

[shaky1105]

Thanks very much for all your replies guys, much appreciated. It appears to be working OK for now so I'll leave it well alone. I might just get rid of the u-bend come the summertime.

Once again thanks

 

[Ryanair]

I have been looking at an intermittent fault which is the exact same as the fault described at the top of this post. The gas fitter came out after I told him I thought the pressure switch was the problem because it had power on the violet wire and nothing on the red wire.

When the air pressure switch was replaced the boiler worked for a few weeks, then it started to play up, working one day but not the next. I found this thread and stripped down the boiler and found the siphon was full of water and black sludge. I cleaned the siphon out and tested it (when working the water level is about 20mm deep) replace all the parts and bingo all working ok.

Removing the syphon is very easy to remove, just a few screws and 20 minute labour.

 

[nicknoo]

Hi sorry to drag up an old post, I have exactly the same problem with the boiler intermittently cutting out. I checked the drain pipe and it was blocked where it meets the soil pipe. I cleaned this out and the boiler worked ok for a few weeks but it started happening again. I have looked and it's been installed with the double trap!!! As described in this post. My question is could the boiler drain connection have been loose (was wet when I undid it) allowing air in all the time then when I fixed the drain issue I tightened it up causing this double trap problem with no vent for the boiler trap? The boiler is in constant use and the post seem to suggest the double trap only causes problems when the boiler is not used and the boiler trap drys out?

I am trying to decide if I will need to clean/change the syphon or if the double trap can cause issues with boilers in regular use? I will remove the external trap anyway but would be good to know if I need to get the syphon checked.

On a side note (sorry) when I was testing the pressure switch I noticed the blue pipe from the fan (co/co2 pipe) connects to the boiler case on what looks like a vent but on the outside of the case there is a nut capping the vent? Is that correct is it used for putting a meter on and should be capped in normal use ?