Condensate pump question

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I tested the small Grundfos condensate pump yesterday that I have ran hose across my loft for.
It's a long run of hose (around 5m upwards from pump with a good gravity drop thereafter to come back down and catch my kitchen sink waste pipe- around 10m from the head- just within acceptable limits according to instructions). I have the hose simply terminating into a plastic hose fitting, going straight into 1.5" plastic waste pipe.

All seems generally fine except after the pump stops pumping, air obviously works back into the condensate hose and you can see water draining up and down (as though a partial syphon effect before things settle (the hose tubing emptying/draining). I think I'm going to hear some water noise from the set-up at my kitchen sink as well but this isn't presently a worry.

Can this aftermath of the pump running (the draining effect) be avoided with a water trap (purely for the condensate water) before the condensate goes into the 1.5" waste pipe? Is that maybe the answer or good practice anyway?
Thanks
 
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Can this aftermath of the pump running (the draining effect) be avoided with a water trap (purely for the condensate water) before the condensate goes into the 1.5" waste pipe? Is that maybe the answer or good practice anyway?
why
 
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Possibly to avoid syphonic suction sucking the water out of the condensation trap in the boiler ? ( which would allow gaseous combustion products to reach the kitchen sink wate pipe )
The pump outlet will have a nrv, the water movement seen in the hose is just settling at a level after the pump stops so creating a water seal to stop any gases passing through.
 
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It maybe isn't necessary, it just doesn't seem ideal.

As bernardgreen is saying, I suspect some water is going back in the direction of the pump.
In which case the sensor in the pump would activate again.
 
As bernardgreen is saying, I suspect some water is going back in the direction of the pump.
our armchair keyboard basher never works never works with condense pumps on boilers but hey what do i know :whistle::whistle:

is it working or leaking if so leave it alone ,
 
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our armchair keyboard basher never works never works with condense pumps on boilers
Then it may not be me you are refering to. It may have been many years ago, before condensing boilers became domestic items, but one thing I got involved in was alarms for when boilers ( very big ones that did produce condensate ) went faulty.
 
and what about condensing pumps ????
yes those big boilers had condensate pumps,

I assume the pump that the OP has ( had ) installed has an air break ( syphon break ) between boiler and the suction input of the pump. The one just pumps lonked to does seem to have a vented tank ( the necessary air break ) http://uk.grundfos.com/products/find-product/conlift-conlift-l.html

But if it doesn't then there is a risk of the boiler's condensate trap being sucked dry.
 
where the hose connects to the pump there's a non return valve so no water can go back into the reservoir once it's in the hose.
the water gets pumped upwards and then out to the drain (in this instance the OP has installed it) then whatever is left in the vertical section just settles down ready to go again.
 
It looks like what I have should be ok then. I expect the long run of hose and the fact the pump is needing to pump upwards nearly 5m is exacerbating any settling after the pump has stopped running. The idea of a small trap was just one that came to mind that might stop air entering the condensate pipe which might have (I'm not totally sure) helped ease the phenomena.

Indeed the Grundfos pump tank isn't sealed to outside.
 

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