Changed piping - homeboost pump not working?

[Rex_Q]

Hi all,

First-time poster. Today I had some leaky 3/4" pipe changed along with a stopcock to 15mm. On the pipe, directly after the stopcock is a Salamander homeboost pump which has helped massively with the pressure. So the pipework went from 3/4" either side of the pump
, to 15mm.

After the pipework was changed, the pump doesn't seem to work. It's lit up with a green light indicating it powered up, but turning taps/shower/flushing toilet not a sausage. The pressure is no better than it was before the pump, so I'm back at stage 1.

Does anyone have any expertise in these Salamander pumps and maybe had a similar issue...might be niche situation though?

Thanks all

 

[Aquarius]

Have you fitted the stopcock in the correct orientation, and is it fully open?

 

[Rex_Q]

Have you fitted the stopcock in the correct orientation, and is it fully open?

Both the external stopcock on the meter, and the stopcock in the house are fully open. I've checked the stopcock and the plumber has fitted it with the arrow going with the flow of water.

I don't suppose it has something to do with flow rate i.e. with the pipe going from 3/4" to 15 mm on the inlet, that now the water flow is not enough to trigger the pump?

 

[Aquarius]

It’s doubtful. Does your plumber not have ideas as to what it is?

 

[Rex_Q]

It’s doubtful. Does your plumber not have ideas as to what it is?

The plumber seems to be washing his hands of the problem. Saying the pump is probably broken and to speak with the manufacturer. It feels odd that it worked before the pipe change over but now its stopped.

The pumps still in warranty, fortunately.

 

[Brambles]

Why have you reduced the inlet pipe size when you are trying to increase your flow rate?

The quickest way to trouble shoot is to disconnect the pump and measure the incoming flow rate - it needs a consistent 3 lpm to trigger the flow switch.

Thereafter make sure that the filters are in place and clean - look for debris that has entered the pump - excess PTFE tape is quite effective in blocking the flow.

Hope this helps

 

[John.g]

Pump re installed "right way round" ?. or inlet/outlet connections swapped.

 

[Rex_Q]

Why have you reduced the inlet pipe size when you are trying to increase your flow rate?

The quickest way to trouble shoot is to disconnect the pump and measure the incoming flow rate - it needs a consistent 3 lpm to trigger the flow switch.

Thereafter make sure that the filters are in place and clean - look for debris that has entered the pump - excess PTFE tape is quite effective in blocking the flow.

Hope this helps

I didn't spec the pipe size, it was all recommended by the plumber - I was following his expertise.

The flow rate seems to be about 4.8l per min.

I'll take the pump off myself and check for those
things - thanks
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Pump re installed "right way round" ?. or inlet/outlet connections swapped.

Yes, it's fitted the correct way.

My gut says it's the pipe size which is the only thing that changed.

 

[John.g]

Hopefully that's the issue although one would think the 4.8 LPM would at least start it.

 

[Ric2013]

It does seem very odd to change from 3/4" bore pipe (which is almost the same as 22mm copper) to 15mm if flow is poor.

However, we don't know how far the 22mm originally extended. If only a few feet of pipe have been reduced in bore to 15mm and there are no other aggravanting circumstances, then it shouldn't make an awful lot of difference to flow rates. I suppose the answer is to know how close to the pump manufacturer's minimum flow to trigger the pump you are in the first place. Hence contact Salamander, as you have already suggested you will do, and ask them the specific question.

Intuitively it might seem logical that if you have a mile of 22mm pipe and even a small section is reduced in bore, then this entire pipe run may as well have been run in a smaller bore pipe. In fact, it doesn't work like this at all.

 

[John.g]

Assuming the 15mm pipe has a ID of 12MM then 10 meters will drop the pressure by 0.6M (0.06bar) for a flow of 4.8 LPM and 3M (0.3bar) at 12 LPM.

 

[Rex_Q]

However, we don't know how far the 22mm originally extended. If only a few feet of pipe have been reduced in bore to 15mm and there are no other aggravanting circumstances, then it shouldn't make an awful lot of difference to flow rates. I suppose the answer is to know how close to the pump manufacturer's minimum flow to trigger the pump you are in the first place. Hence contact Salamander, as you have already suggested you will do, and ask them the specific question.

Hi Ric2013 - so I just measured the pipe work. The total length that has been replaced is 6 metres worth of old 25mm down to 15mm. This includes a 30cm run before the pump with the rest after the pump. In your experience would this make a difference? The documentation for the pump states that it needs a flow rate of 3lpm before and after the pump....
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Assuming the 15mm pipe has a ID of 12MM then 10 meters will drop the pressure by 0.6M (0.06bar) for a flow of 4.8 LPM and 3M (0.3bar) at 12 LPM.

I need to be honest John, I am not entirely sure what this is telling me, sorry I'm a layman

 

[John.g]

What it means is that 6m of 15mm pipe work should have little or no effect on the flow rate, but 4.8 LPM seems exceptionally low except that you have practically no mains pressure or there is a blockage or a throttled valve/stopcock (which was checked open by yourself.) I think you said you were going to remove the pump to check a few things including the flow rate, so maybe this 4.8 LPM is with the pump removed.

 

[Ric2013]

Right. So you need a flow of 3lpm to make the pump kick in. 3lpm is an exceptionally low flow rate and would very easily be achievable through 15mm pipe in normal circumstances so I would be highly surprised if the 15mm pipe has anything to do with the problem. Even if the new pipework were restrictive, the fact that the pipework only "narrows" 30cm before the pump is a good thing (pumps don't usually like to suck and are happier pushing against a restriction than sucking on a restrictive pipe).

The flow through your taps is going to be equal to the flow through the pump. Open a tap fully. Stick a bucket under it. Time a minute. How many litres are in the bucket? If over 3 and the pump isn't kicking in then something's wrong with the pump or power supply to the pump.

If under 3 litres, try opening multiple taps. Some form of blockage or restriction, it would seem. Will the pump kick in with multiple taps open?

 

[wayneh]

did you get to the bottom of this?
I have a very similar issue, definitely over 3lpm its (around 6lpm) my pump unfortunately is just out of warranty and the manufacturer suspects a faulty flow sensor. Been hoping to find someone who's taken one of these apart and had a play...