Water pump problems, can anyone help?

[Big Paul]

Hi, I have just completed new build house in Phanom Phrai district, the local builders installed a water tank and pump but the water surges and pump makes loud thumping noise when water is opened, they say this is just the way it is and are not doing anything further.

can anyone help with possible solution as I am sure it is not correct.

Any advice will be much appreciated.

I have included pictures of pump cover and tank. 

 

 

[Kwasaki]

3 minutes ago, Big Paul said:

can anyone help with possible solution as I am sure it is not correct.

Yeah your right with-hold some payment if possible.

Where do the water pipes run is it them that make the noise. ?

Have you run the water fully from all parts of the house the noise could be trapped air. ?

Maybe the pump is giving too much pressure can it be adjusted. ?

[metisdead]

Moving to the DIY forum. 

[Big Paul]

I have opened both of the showers and taps etc...  but same issue, I cannot find a manual for pump anywhere so far. But I will look again at pump.

the pipe comes from tank to pump then house, it is a short distance to all taps the kitchen being furthest about 15 feet or so. 

[Big Paul]

5 minutes ago, metisdead said:

Moving to the DIY forum. 

Apologies I didn’t see DIY forum listed. ????

[metisdead]

Just now, Big Paul said:

Apologies I didn’t see DIY forum listed. ????

 

No worries, there should be some helpful advice offered here. 

[Big Paul]

16 minutes ago, Kwasaki said:

Yeah your right with-hold some payment if possible.

Where do the water pipes run is it them that make the noise. ?

Have you run the water fully from all parts of the house the noise could be trapped air. ?

Maybe the pump is giving too much pressure can it be adjusted. ?

It is actual pump making noise, the flexible pipes next to toilet and shower shake when any outlet is opened. 

[Crossy]

What's the on-off cycle time of the pump? Does it stay on if you open all the taps?

 

Try unscrewing the pressure tank (power off and open a tap) and shake out any water that's inside. Does the tank have a tyre-type valve on the end (do NOT remove any plastic plugs)?

 

It's a new build so the pressure tank shouldn't be water-logged but one never knows.

 

[steve73]

There was a similar question asked a few weeks ago.  I, and many others replied, and they are mostly probably relevant here.

I'm sorry, but I can't get anywhere with TV's search facility, but I'm sure someone should be able to find the relevant topic and provide a link.

[bankruatsteve]

Are all the valves for input and output for the pump full open?

[Big Paul]

3 hours ago, Crossy said:

What's the on-off cycle time of the pump? Does it stay on if you open all the taps?

 

Try unscrewing the pressure tank (power off and open a tap) and shake out any water that's inside. Does the tank have a tyre-type valve on the end (do NOT remove any plastic plugs)?

 

It's a new build so the pressure tank shouldn't be water-logged but one never knows.

 

Hi Crossy, I have tried opening all taps at same time, it seems to run constantly but if I shut one off then it starts surging again. The lid of the main water tank is loose I am not sure if it should be tightened all the way or not. I am not sure what part I should unscrew to shake water out.

i have uploaded a couple more pictures.

thanks for advice. 

[Lacessit]

Can you find a manual for the pump online? Most appliances have a trouble-shooting guide in their manuals, you may get lucky.

[Crossy]

The pressure tank is the grey cylinder on top of the pump. Is the brass bit on top a tyre type valve? Does the pressure tank have a label with a working pressure?

 

But your problem may be the outlet flow being restricted by that run of 1/2" pipe. 

[Dumbastheycome]

4 hours ago, Big Paul said:

It is actual pump making noise, the flexible pipes next to toilet and shower shake when any outlet is opened. 

Whats happens if you turn off the outlet, turn off the pump, then open the outlet? Does it "surge" until the pressure drops?

These pumps  have a  valve that introduces  air to add to the little pressure tank to keep  pressure on the  automatic switch. It may be  faulty and there is  too much air in the tank.

[Fruit Trader]

The pump is the LuckyPro style most likely from same widely branded Chinese stable. These pumps are hit and miss in the quality dept so it could be faulty pressure switch or bladder causing it to throw a fit. Call back the installer. 

[Fruit Trader]

16 minutes ago, Dumbastheycome said:

These pumps  have a  valve that introduces  air to add to the little pressure tank to keep  pressure on the  automatic switch. It may be  faulty and there is  too much air in the tank.

These compact pumps use a bladder type pressure tank unlike many other pumps which use air space maintained by an injector valve.

[steve73]

23 minutes ago, Fruit Trader said:

The pump is the LuckyPro style most likely from same widely branded Chinese stable. These pumps are hit and miss in the quality dept so it could be faulty pressure switch or bladder causing it to throw a fit. Call back the installer. 

Agreed - these pumps are the cheapest of the cheap... (but easy to remedy your problem). 

You (OP) says that when all taps are open the pump runs fine, so this eliminates the problem of too small a suction pipework.  But when you restrict the flowrate the pump cycles... So...

 

If it cycles quickly (bang/bang/bang...) it indicates the air tank is knackered - probably a failed bladder.  It's easiest to fit your own "expansion" tank using a 2m length of 2" PVC mounted vertically... connect it to the outlet.. eg. just before the tap connection, via a 1/2' to 2" reducer, and fit another 2" to 1/2" at the top with a valve to allow you to drain it if required... but don't vent the air.. just let it compress in the pipe.       

 

If the pump cycles more slowly, say every 5-10 seconds or longer, it suggests the pressure switch is incorrectly set (these cheap pumps can be set all over the place, and are usually a bit on the low side).  Take the black plastic cover off, and then adjust the small screw (using an insulated screwdriver) until the pump stops cycling... If it keeps running when all the taps are closed, you'll need to back it off a little or it'll damage the pump.  If you cant get the pump to run continually then the pressure switch itself is probably u/s, and can be replaced on its own.

 

The pumps are only about 1,500 to 1,800 new anyway.. (The switch itself 150-200bt if that's the problem).. Your installer will probably charge more than that to visit, unless he'll repair/replace FoC.  

[Dumbastheycome]

8 minutes ago, Fruit Trader said:

These compact pumps use a bladder type pressure tank unlike many other pumps which use air space maintained by an injector valve.

Ok.  Yes. Failed to note  the pump format. So other than air bubbles an explanation to thumping noises  and vibration  may be some item in the pump impeller....a bit of plastic?

The setup looks  very simple so other than air hydraulics from somewhere  in the extended pipeline suggests something about the pump itself.

 

[Fruit Trader]

1 minute ago, Dumbastheycome said:

Ok.  Yes. Failed to note  the pump format. So other than air bubbles an explanation to thumping noises  and vibration  may be some item in the pump impeller....a bit of plastic?

The setup looks  very simple so other than air hydraulics from somewhere  in the extended pipeline suggests something about the pump itself.

 

You got to appreciate the Thai reduction plumbing though. Guess it was just too hard to keep it all at 1" up to the outlet tee.

[Dumbastheycome]

Just now, Fruit Trader said:

You got to appreciate the Thai reduction plumbing though. Guess it was just too hard to keep it all at 1" up to the outlet tee.

lol.

[sometimewoodworker]

1 hour ago, Big Paul said:

Hi Crossy, I have tried opening all taps at same time, it seems to run constantly but if I shut one off then it starts surging again. The lid of the main water tank is loose I am not sure if it should be tightened all the way or not. I am not sure what part I should unscrew to shake water out.

i have uploaded a couple more pictures.

thanks for advice. 

While the response so far will probably help to find the problem I  would at a minimum scrap the tank outlet and piping to the pump and replace it with 1" that will ensure that the pump is not being starved and so avoid cavitation. It is such a short run it won't cost much to do, it might possibly cure the problem.

[CGW]

Pictures remind me why I do all my own plumbing 

If your thinking of calling a Thai plumber, look at these pictures? - you can do better ???? 

[Thainesss]

1 hour ago, sometimewoodworker said:

I  would at a minimum scrap the tank outlet and piping to the pump and replace it with 1" that will ensure that the pump is not being starved and so avoid cavitation.

Yes, I agree. 1" or 1 1/4" depending on what the pump inlet size is. 

 

Everything else looks installed fine other than the cheapness of the pump. 

 

IMO bein 1/2" AFTER the pump shouldn't cause this problem. 

 

If it was me, and it was my house, I would try to change that tank to pump piping, and if that doesnt work, then I would change the pump to a Hitachi or Mitsubishi automatic pump. 

 

OP, these pumps are supposed to run all the time when a tap is open, and shut off when that tap is closed, what they arent supposed to do is 'hammer' or switch on an off. (unless youve got something that uses VERY little water when its operating). 

[Andrew Dwyer]

There was a similar question asked a few weeks ago.  I, and many others replied, and they are mostly probably relevant here.
I'm sorry, but I can't get anywhere with TV's search facility, but I'm sure someone should be able to find the relevant topic and provide a link.

Steve I think you are referring to my thread “ water pump pulsing “ also in DIY forum.

My issue was different in that the pump was cycling every 3 seconds or so after I drained it ( and the tank ) to reposition it and previous, to me draining it, it would run all the time when ever a toilet was flushed or a tap opened.

I got lots of great advice and the problem resolved itself but it did take 2 weeks !!
It was probably due to voltage changes or I’m thinking now more likely to be air trapped somewhere, possibly in the bladder tank .

[steve73]

2 hours ago, Andrew Dwyer said:

 

 

Steve I think you are referring to my thread “ water pump pulsing “ also in DIY forum.

My issue was different in that the pump was cycling every 3 seconds or so after I drained it ( and the tank ) to reposition it and previous, to me draining it, it would run all the time when ever a toilet was flushed or a tap opened.

I got lots of great advice and the problem resolved itself but it did take 2 weeks !!
It was probably due to voltage changes or I’m thinking now more likely to be air trapped somewhere, possibly in the bladder tank .

 

Thinking more about this, your problem was almost certainly due to stirring up dirt and sludge when you moved the tank.  This sludge would then have partially blocked any filters on the inlets to your toilet cistern, or shower units, reducing the flow below the minimum required for stable pump operation.  Over time this sludge may have slowly cleared, allowing the flow to increase again sufficient to keep the pump running continuously.  Air in the system would not have caused this slow cycling... if anything it would add extra "surge" capacity, and slowed the cycling even more.

 

Anyway, good to know your problem is fixed.

 

For the OP here.... if this is a new system it's likely to be poorly sized, or again could be blocked filters (especially if the fitters used a cutting disc rather than a proper pipe-cutter).

[bankruatsteve]

I'm inclined, as others, to think something not quite right with the pump.  But, this connection to the 1" looks very strange.

 

 

[VocalNeal]

Big Paul are you a handy kind of guy?  It is possible that your pump has an internal check valve and the spring is broken/missing. This results in a slight delay of the check valve closing when the pump stops allowing the water to flow backwards until the valve slams shut hence the banging sound. 

I have replaced the spring in a common yellow Mitsubishi pump but that was a while ago and I can't remember exactly where is was.

 

Have a look under the grey plastic plug.

[Fruit Trader]

1 hour ago, bankruatsteve said:

I'm inclined, as others, to think something not quite right with the pump.  But, this connection to the 1" looks very strange.

 

 

Yes it does look strange. Black soot marks and discoloration are often evidence that someone has been burning out pipe which is done to reclaim used fittings. The female adapter at the tap is second hand for sure and the tap back at the tank looks like its seen better days.

 

All quite typical of multi trade plumbing. Tomorrow the same guy might be wearing the electricians hat. 

[eero]

Try assemble backpressure valve betveen pump and Water tank.

Before I have big proplem but one specialist tell me to do it and it helps.

Best Regards

Eero, from Chaiyaphum

[eero]

I agree that you tubes are too small, change bigger and install backpressure valve.