Waste pump problem

[Rybo_1]

Evening all,

Got a problem with a waste pump which is serving two coffee machines.

The pump in question is a Pump Technology Drainmaster. Fitted many of these without a hitch until now.

The problem is this, when the pump pumps away, water comes out of an upstand under an adjacent sink. The waste run goes up immediately after the pump and then into the supplied check valve and then loops back down underground a raised counter all in Swept elbows as far apart as possible. Emerging from under the floor it then loop back up and over and in to a gravity 1 1/2 drain. The pumped is in 1 1/4.

The gravity run is clear so it's not blocked and backing up at the lowest point.

I have the high level.float fitted and always have bar one occasion. I'm thinking this could be the issue. Where it's pumping a way a rather large volume of water could it be taking a while to drain away from the 1 1/2 run thus meaning it comes out of the upstand. I was going to try fitting a low level float and see if pumping a lower volume of water away could fix this.

Any opinions/suggestions would be greatly appreciated here! Especially those of rpm! No pressure mate.

Thanks

 

[JCplumb]

Unless you can give it its own 50mm run I'd agree with the low level float, bear in mind the increased chance of smells with a sump that's almost always empty.
Only ever worked on one before in a cellar drop in a pub, it was a high level one - the float was nearly vertical before it kicked in, connected it to the drain that the glasswasher taps into and it tried to fill the glasswasher when it kicked in so gave it a run of its own and had no problems. They kick out more pressure than you'd think.

 

[chris watkins]

Is the up stand trapped ? if not could you if one or a non-return on the leg up to it.

 

[rpm]

Would I be correct in thinking the pipe from the basin joins the discharge pipe at floor level with a sweeped T? Any chance this T is facing the wrong way therefore encouraging water up the pipe to the basin?

Based on the pipe run given, up > down > level > and up again the level section will have water in it so as the pump discharge`s the new water it is hitting this water and sending either water or air up to the basin, as Chris said fitting a one way valve in the pipe is the easiest way to over come the problem and I believe Jung (The pump in the tank) say use 32mm pipe, don`t know of any pump this size using 50mm discharge pipe.

If however the pipe from the basin is piped directly into the tank at low level then there is another possible reason for the problem.

 

[rpm]

I'd agree with the low level float, bear in mind the increased chance of smells with a sump that's almost always empty.
Only ever worked on one before in a cellar drop in a pub, it was a high level one - the float was nearly vertical before it kicked in.

Low level float will not increase smells just means the pump activates more often, from memory doesn`t the Drainmaster have a Charcoal filter fitted? (could be an optional fitting) and all Torpedo type floats activate close to the lid.

 

[rpm]

Only ever worked on one before in a cellar drop in a pub, it was a high level one - the float was nearly vertical before it kicked in, connected it to the drain that the glasswasher taps into and it tried to fill the glasswasher when it kicked in

No surprise there then lol, pressure v`s gravity. Only way round that is to join the gravity fed pipe to the pressures discharge pipe from as high up as you can.

 

[Rybo_1]

The upstand is trapped and there is literally no room to fit a check valve under the sink unit.

The gravity pipe where the pumped run Tees in (which is 100% in the correct orientation) is around 400mm above FFL.

And correct about the charcoal filter. I can't see why changing the float would affect any bad smells anyway.

So been able to get hold of a low level float today so will be fitting tomorrow. Hopefully the lower volume of.water will mean it flows away easier and doesn't back up! Touch wood

 

[rpm]

So been able to get hold of a low level float today so will be fitting tomorrow. Hopefully tlower volume of.water will mean it flows away easier and doesn't back up! Touch wood

Still going to be the same pressure though, wanna hear how this goes changing the float please.

 

[rpm]

Any update with the low level float Rybo?