Water pump problems, can anyone help?

[Mister T]

1 hour ago, eero said:

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

Yep, had similar problem from new, mitsubishi pump. A guy from Thai Watsadu came out and said to put in bigger pipes or have 4 mtr of pipe before the first outlet, did it myself and it solved the banging problem.

[xtrnuno41]

ISnt the capacity of the pump too big. Big is not always better.

You said if more taps are open its ok and if you close one then it starts making vibrations.

SO could be, you have backflow, returning to pump, which the pump doesnt like and start vibrating inside. It's too big.

As it is new, ok there could be factory faults in it, it should run quiet

I think it is a very real big sized pump. I compare with my gf house where is a tiny (about half the size and probably capacity)

pump and giving good water pressure and flow, maybe already to high, but its quiet. 

To solve it , i think , too bad you dont have specs and isnt to be found, you could have another pump, lower in capacity.

How many times it occurs you open 2 taps or more? Nihil.

Or on pressure side make a pipe back to the vessel with a valve in it to control water flow. You return water to the tank, circulating.

OK in that case you dont use the full capacity of the pump and using more electricity then normally wise with a smaller pump.

 

If you leave it, the internal mechanical parts are wearing quick and it will break down. Then you need a new pump.

ALso vibrations will effect tubing ( everything in lining) and also wear it, so it can break as well. 

 

[Dania2019]

The pump has a presostat, you can turn i down - I hope this help you

 

[rocket3rider]

Two things I can't see are:

One way valve to ensure flow only one way and

A tank bypass with a stopcock (in case your power goes out or the pumps dies).

[CGW]

1 hour ago, rocket3rider said:

A tank bypass with a stopcock (in case your power goes out or the pumps dies).

Yes, need a line from inlet (fill line to tank) to discharge line after the pump, with a valve and a check valve in the line if he wants water - for whatever reason in the "house".

Edited April 25, 2019 by CGW

[rutteketuut]

You built a new house so I suppose your waterpump is brand new, very unlikely there is something wrong with the pump . What I would do first is check the water pipe and connections from the watertank to the inlet of your waterpump. If this sucks air, you surely have a problem with the pump. Then there's air in the system all the time..

[Inuk]

Is the photo below the pump in question. If so it is made by Xinya, Zhejiang, PRC - see alibaba water pumps.

Is the house two storey or more?  Is the ground floor of the house on the same level as the holding tank?   Start at meter and disconnect the pipe to check mains smooth flow constant at whatever your water authority confirms e.g. 2 bar/30 psi at ground level average.

You may also need to install a one way inlet valve (brass) between the meter and the tank if this has not been done to retain water tank level if the mains are broken. Not unusual.

Assuming the tank is full, disconnect at the exit point of the pump, fit a slave flexi pipe, switch on to check smooth constant flow from pump.

I assume the T Piece downward carries water to the house. Builders are famous for dropping cement down pipes. If this is the case the only solution is Dyno Rod but I don't think they are here in Thailand or run a new pipe along the ground in parallel to verify smooth flow to the house. Then you have identified thatthe problem lies in the house water pipes system. Back to the builder.

[mikecha]

IS   the pump from a bore well  self priming>

u could    try to start closing the inlet valve little by little till u have a balance inlet outlet if u get a balance then it is possible pump is to big  also like many said cam be air suction causing cavitation  check any leat inlet piping

 

if u ar cucking water from a well u need a non return valve at bottem of suction pipe then u dont get air .

if u are on mains why  dp u have such a big buffer tank 

 

[Rally123]

Always buy from 'Lazada TH'. They give you the right to return within 7 days of delivery.

[whiteman]

amazing thailand hope you kept some money back from the installer they sould like a fly b y night job

[The Old Bull]

You need a check valve between the tank and the pump. It has to be the spring type not the flapper type.

[utalkin2me]

Where did they get that logo from, a pimp? 

[Joedoebarinio]

The problem will be with the pressure vessel on the top of the pump. Somehow the bag inside has lost pressure. It’s either burst or something let the air out of the valve on the end of it. How much pressure should be in it I don’t know without the manual. Put a tyre pressure gauge on it and see what you get. 

The vessel compensates for water hammer.

Edited April 26, 2019 by Joedoebarinio
Spelling error.

[Joedoebarinio]

Play around with the pressure switch if you must. But without pressure in the vessel the system will hammer, all day. 

[mogandave]

Yes, need a line from inlet (fill line to tank) to discharge line after the pump, with a valve and a check valve in the line if he wants water - for whatever reason in the "house".

Exactly. This will allow for decent flow in the house with the power off or the pump down, as well as (probably) stopping the pump from coming on just to wash your hands or refill the toilet...

[Big Paul]

Hi all, I am back in Thailand now, looking at this pump again, I can confirm it does have tyre valve on side of pressure tank, I will try to check pressure today and maybe get the guy from bike shop in village to add air if required. 

The same builder installed another pump for local person in village told them the same thing. ‘This is how they run’ 

I haven’t been able to get hold of him as he seems to be avoiding me and my wife as we need a few things looked at in house! Not really a good experience with my first dealings with Thai builders!

[Big Paul]

On 4/24/2019 at 4:29 PM, Crossy said:

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. 

Hi Crossy, 

thank you for advice,

i am back trying to resolve this problem again, yesterday I checked pressure on tyre type valve when I depressed it water came out before any air, I unscrewed the cylinder held valve in and drained all water from it, screwed cylinder back in added pressure to 1.0 bar as on label. It is now better but still surges with cycle time of about 5 seconds rather than constantly banging/ surging. However now the water in kitchen which is furthest outlet from pump is just very low pressure not much more than a trickle. Water in both bathrooms seems ok but still surging. 

Any help much appreciated.

paul. 

[bankruatsteve]

Broken bladder on the pressure tank?  Replace shouldn't be hard to find.

[Crossy]

21 minutes ago, bankruatsteve said:

Broken bladder on the pressure tank?  Replace shouldn't be hard to find.

 

Yeah, there shouldn't have been any water coming from the air valve.

[Big Paul]

Ok I will try to find one and replace.

thank you. 

 

[David B in Thailand]

Did Global House offer an installation service for the Water Pump and Water Tank you paid for?  HomePro offers installation services for water pumps and Water tanks. 

[Big Paul]

15 hours ago, David B in Thailand said:

Did Global House offer an installation service for the Water Pump and Water Tank you paid for?  HomePro offers installation services for water pumps and Water tanks. 

Unfortunately I was in the UK when this was installed, so did not get to oversee it,  it was done by builders that made house. 

[Big Paul]

22 hours ago, Crossy said:

 

Yeah, there shouldn't have been any water coming from the air valve.

Yesterday I went everywhere I could think of locally but was unable to find this part. 

I looked at it again this morning, but not finding any water coming from air valve now?? I am just thinking if it was not installed correctly could this of caused the water to be coming out of valve? 

Still no pressure in kitchen though, I am thinking maybe an air lock in pipe? This tap was turned on when I turned off pump! 

Any ideas how to fix it?

if I don’t resolve it today I am thinking buying a decent pump and trying to find someone competent to install!! 

I didn’t really want to buy another pump as this one is new and the builders should be responsible but I can’t seem to contact them. They have had their money so I doubt they will be back! 

[Crossy]

If you're getting decent pressure at some taps then the pump is working.

 

Check the kitchen tap, it will have a filter thingy in the end, unscrew it and clean (try it with the filter out), also check the wall outlet for debris. There could well be bits in the pipe so it's worth removing the valve from the wall under the sink and checking in there (pump off of course or you'll get wet).

 

[tjo o tjim]

I think @steve73 had the right suggestion for you in post 17– build your own pressure reservoir out of 2” PVC pipe at the outlet of the pump.  Cheap, simple, and easy to DIY.  You can mount it against the wall of the house easily enough.  Just need to cap off the bladder tank.  No sense replacing the pump itself. 

[mogandave]

I agree with Crosby. Assuming only one tap is opened at a time, and assuming they are all on the same level, the pressure and flow at all the taps should be about the same.

[Big Paul]

2 hours ago, Crossy said:

If you're getting decent pressure at some taps then the pump is working.

 

Check the kitchen tap, it will have a filter thingy in the end, unscrew it and clean (try it with the filter out), also check the wall outlet for debris. There could well be bits in the pipe so it's worth removing the valve from the wall under the sink and checking in there (pump off of course or you'll get wet).

 

Yes filter on tap was full of debris, now have good pressure in kitchen.

 

pump still cycling about 8 seconds now, I will try to get someone to change pipe from tank to pump where it has been reduced, hopefully this will help solve problem.

 

thank you.

[steve73]

3 hours ago, Crossy said:

If you're getting decent pressure at some taps then the pump is working.

 

Check the kitchen tap, it will have a filter thingy in the end, unscrew it and clean (try it with the filter out), also check the wall outlet for debris. There could well be bits in the pipe so it's worth removing the valve from the wall under the sink and checking in there (pump off of course or you'll get wet).

 

It does sound as if the faucet in the tap is blocked (most likely from PVC pipe cuttings if it's a new installation).  The resulting low flowrate then causes the pump to cycle on--off--on--off (as apposed to on/off/on/off, which would indicate a damaged bladder).

 

If you find the faucel keeps blocking up, you would need to shut off the pump, unscrew the tap completely then switch the pump back on and allow the water to run full-bore for a few minutes to clear out all debris.

 

btw, unless you have a proper sand filter somewhere in your incoming system, over the years (or a few outside repairs) you can get lots of sand/grit with gov't water (although probably not as much compared to your own bore-hole) but it doesn't take much to get a few inches in the bottom of your storage tank, which can be enough to keep blocking your faucets.)

[steve73]

1 hour ago, Big Paul said:

Yes filter on tap was full of debris, now have good pressure in kitchen.

 

pump still cycling about 8 seconds now, I will try to get someone to change pipe from tank to pump where it has been reduced, hopefully this will help solve problem.

 

thank you.

Sorry - missed this post.. 8 seconds cycling is pretty typical of a slightly over-sized pump and not worth worrying about.  If you open 2 taps it would probably run fine.

Changing the suction pipework won't make any difference.

If you really need to make it run continuously then you'll need to adjust the pressure switch settings... with care.