Condensate pump repeatedly activating

[Forbez]

Hi all, after what started out as a crap start to the year in the house finally started to get back on track, before the latest adventure of ‘Money Pit’

Recently we’ve noticed that the Sauermann 1820 condensate pump from our gas central heating seems to be activating very regularly. From anything from every 2 minutes, through to 15-20 minutes, it makes what sounds like a purge, and settles down. The issue is the boiler and condensate are in the airing cupboard in my sons room, so it’s noisy at night for him.
All the heating and water seem fine, so I suspect it’s a condensate issue rather than boiler.
I’m trying to get hold of our normal plumber, but have had no answer or returned calls this week. So I’m reaching out to the great collective minds of this forum, as to why it maybe constantly activating, and what I could do to resolve it.

The boiler is a Vaillant Ecotec pro28, and wasn’t serviced last year due to COVID. We’re trying to book the plumber in to do this, but to no avail at present.

from what I’ve read the condensates should be cleaned at the time of service too, so maybe it’s a build up of grime or dirt in the water in the condensate?
Any suggestions? Thanks Tom

 

[CBW]

Is this with heating/hot water being ran, or regardless?

 

[ianmcd]

Are you having to keep topping the pressure up on the system ?

 

[Forbez]

Hi both, cheers for the responses.

Ian, I’ve only topped it up once in about 18months, and even then it was only a very small amount.

Chris, it seems to happen when the water and / or heating is being used. Aswell as when it’s not in use.

We had the boiler serviced yesterday, and the engineer had a look at the issue. He disconnected the pipe that takes away from the pump, and it was full of water and it emptied out. It didn’t seem to be blocked.
Is this correct that it’s full of water?


It stopped pumping for most of the day, and had started back again this morning (about 18 hours after being emptied)

I emptied the pipe again this morning and it seems to stop the issue.

This makes me think that when the water is being pumped away, up into the attic and across to the soil pipe. Maybe it’s sitting in pipe and is not flowing away, and feeding back into the pump.
Should the pipe stay full of water?

Maybe a one way valve is allowing the water to drop back into the pump?

thanks Tom

 

[ianmcd]

That is your problem, the exit pipe should be clear, follow the hose and look for kinks or blockages

 

[Forbez]

Thanks Ian,
Funnily I had taken these pictures since posting earlier.

I’m guessing that the exit pipe should be a straight line and not with right angled bends.

we’ve lived in the house for 7 years and the issue has only just started in the last week or so.

The pot that the pump sits on, has water in there, is this correct, and shout the water be cleaned out? As if I look down into it, the water looks a little murky or dirty. Should it be cleaned out?

Your help is very much appreciated, thanks Tom.

 

[ianmcd]

no the pump itself has a sump in it, with a float switch, when the condensate reaches the correct level, the pump activates and empties the condensate to a level that cant be altered, your second pic is not very clear but at the top that hose doesnt look too clever, first thing to do is remove and clean the non return valve, it just pulls off no tools needed, give it a good flush through with a cold tap and see if that stops it

 

[Forbez]

Cheers Ian, thanks. Will give it a clear out in the morning. I can hear it buzzing away now. Cheers for being so helpful. I’ll let you know how it goes.

The hose in the second pic is just abit loose, no kink or twists in it. Is it worth making it a straight run, up and through the ceiling, rather than those bends? It’s in an airing cupboard, so it’s no issue with how it looks.

 

[Forbez]

I've removed and cleaned the non return valve this morning. The pump was going last night, so the exit pipe was full of water.

I've rerouted the piping, to make it a straighter run upwards, will this be of any benefit?

I'm guessing that the exit pipe fills itself with water, and then over time and during the pumping, the water just gets pushed along the piping.

Hopefully, the Non return valve will be cleaned out now. It seemed to free up the float a little, when I was running the water through it, also let it soak in a little warm water too.
I cleaned out the sump too, as the water in there looked dirty. So I guess that'll take a little time to refill, before it pumps again. So it may be a little while before i'll see if this has helped with the issue.


Many thanks for your help so far Ian.

 

[ianmcd]

Just pour some water into the sump until the float switch operates, then see if it just pumps for a short burst then stops, if it does then you have sorted it

 

[Forbez]

I'm now sat here thinking, that's so bloody obvious, why didn't I think of that!

 

[Forbez]

So I topped it up with water, and in 22 minutes its pumped 5 times.

The water pressure on the boiler is fine, heating works, hot water works.

Pump still activates, even when the hot water is running.


Is it worth getting a new Non return valve as a precaution? In case its back filling.


Or should I remove the inlet from the boiler that feeds into the pump, put that into a bucket. And then if the pump goes off, then it suggests that the sump is refilling through the NRV.

And if it doesn't, then seemingly there's water flowing from the boiler in. And I can guage that from the amount of water in a bucket.

 

[Forbez]

Been into the attic, and no clear kinks or bends.
It pumped whilst I was up there and I could see the water moving along the pipe, upto the point where it joins onto a plastic PVC pipe.

I've tried to create a high point where it initially goes up and into the attic, but not hugely successful, hopefully enough to stop it flowing back.

But the pump seems as active as it has been.


I will now try removing the inlet, pipe and separating the pump from the boiler.

 

[ianmcd]

would be better if you had a short piece of hose and put it on after the NRV and empty it into a bucket where nothing can run back , if the pump keeps activting like that then it is a faulty pump, but it is usually and NRV or restriction somewhere on the hose

 

[Forbez]

Will see what I can pull together. I've been caught out with the pump going off once, with the exit pipe removed.

I now have issues with the pump, and an angry missus.