Keroscene combi boiler has stopped producing by-product water

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We have a Grant Vortex 36Kw combi keroscene burning boiler,
which has two expansion vessels fitted to the heating side of the boiler.

Recently we added a bit of pressure to one of the expansion vessels.
Since then the boiler has stopped producing the by-product water that's produced when you burn keroscene.
Before that the boiler regularly filled a bucket in the garage with this water, that we emptied every few weeks.

What could cause the boiler to stop producing this by-product water.

We have had this boiler 12 years and it has always produced by-product water.
Obviously something has changed.

Should we worry,
could topping up an expansion vessel do this,
is this caused by something else?
 
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Sounds like the boiler hasn't been installed correctly for a start. You say you added some pressure to one of the expansion vessels. What was the reason for doing this? What did you do to achieve it? Where is this "by-product water" coming from? Some photos would help
 
Sounds like the boiler hasn't been installed correctly for a start.
I installed it myself.
That said it has worked flawlessly apart from a periodic & sudden depressurisation problem that no engineer has been able to identify the cause of. This de-pressurisation happens may be once a month and started a number of years after the boiler was installed. It was installed 12 years ago.

You say you added some pressure to one of the expansion vessels. What was the reason for doing this?
Brother who is heating engineer suggested it might be the source of the de-pressurisation problem.
I did'nt think so, but went along with doing it anyway, becasue I'm out of ideas on this long running de-pressurisation saga.

What did you do to achieve it
Got the air pump out and added some pressure on the schrader valve at the bottom of the expansion vessel.
The pressure seemed to be Ok at about a bar, before I added air. I topped it up to about 1.5 bar while the water heating circuit was de-pressurised, so I might let the air out again and bring it back to a bar, and see if that fixes it.

Where is this "by-product water" coming from?
It comes out a pipe inside the boiler & goes through the white cylindrical thing shown sitting astride the red bucket, it goes into, shown below.
It's just a drip drip burn off water feed.
It is supposed to do this.
I never got round to digging a connection to the drain for it hence the bucket.

Some photos would help
See below
IMG_20200923_103238.jpg

IMG_20200923_103227.jpg
 
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1. Assuming that the water "by product" is actually the condensate.
2. As Lower suggests, possible blockage in the condensate pipe run. Try removing that white plastic thing from the end of the condensate pipe and see if it makes a difference.
3. If you have set the boiler to run hotter (i.e. the return temperature is greater than 55 degrees), it won't go into condensing mode, or at least, not as much.
 
If you let the air out of the expansion vessel, does water come out of the schrader valve?
Have you checked the other boiler components like the auto air vents and safety valves?
If the original expansion vessel is still fitted inside the boiler, do you have a leak from that safety valve?
 
1. Assuming that the water "by product" is actually the condensate.
2. As Lower suggests, possible blockage in the condensate pipe run. Try removing that white plastic thing from the end of the condensate pipe and see if it makes a difference.
I have tried removing the white plastic thing.
Removing it does not allow condensate to flow.

3. If you have set the boiler to run hotter (i.e. the return temperature is greater than 55 degrees), it won't go into condensing mode, or at least, not as much.
No changes have been made to any boiler settings.
Not on the house thermostat and not on the boiler itself.
 
Have you actually got the heating on ?
The heating is still working as expected.
Can't tell if the radiators are slightly less hot than normal becasue each time I check them the set house temperature has already been reached.
It seems the system is delivering the same amount of heat as before.
 
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