Water leak maybe pump faulty

[Davejf2017]

The water pump keeps starting every 20 minutes.I have checked all taps showers inside and out for leaks all seem good and have also dug up various sections of blue plastic pipe and replaced it as near various plants.When I had the water to the pump turned off both sides of the pump the pump started for a few seconds then went off could it be that the water pump is faulty if not it mens that I will have to get all the underground blue plastic piping replaced.what is your idea maybe Crossy has a idea as he seems top on electrics and other diy.

[Crossy]

If you close the valve on the outlet of the pump (leave the inlet open) does it still cycle?

 

If you close the valve on the inlet of the pump (leave the outlet open) does it still cycle?

 

Moving to DIY.

 

[Davejf2017]

I had valves closed on inlet and outlet of pump while i was changing a tap as thought tap was leaking and heard pump start up for few seconds then stop.

[RichCor]

29 minutes ago, Davejf2017 said:

I had valves closed on inlet and outlet of pump while i was changing a tap as thought tap was leaking and heard pump start up for few seconds then stop.

If you had both valves closed and the pump still ran a few times then that suggests either:

 

A. The pressure sensor is faulty, and/or

B. The valves are leaking

 

The pump should be inactive with both valves closed. Probably ants or other small critters have moved into the sensor. Otherwise you may have a valve leak on the inlet (most likely) allowing water to egress back upstream, or on the outlet valve and system leak you have yet to locate.

 

 

[VocalNeal]

May we have a picture of the pump?  So we can determine what type it is.

 

15 minutes ago, RichCor said:

Probably ants or other small critters have moved into the sensor.

They'd need scuba gear?

 

 

Either the tank under the pump has lost it air fill over time or the integral check valve is leaking and needs to be replaced.

Edited May 20, 2020 by VocalNeal

[AtlasAus]

I have just gone through this. 

 

It ended up being a "flapper" valve type thing on the inlet line, it had lost nearly all of it's flapper ???? You will need to take it out and have a look to see if it is functioning. 

 

The "engineer" found it, which was the 3rd person we had look at it. 

[bankruatsteve]

4 minutes ago, AtlasAus said:

It ended up being a "flapper" valve type thing on the inlet line,

Was that the inlet line from the meter?  Was it a "check valve" (NRV)?

[RichCor]

15 minutes ago, VocalNeal said:

They'd need scuba gear?

As the pressure sensor is usually a electro/mechanical device it will have a wet and a dry side.

 

Something is triggering the pump to run. While it could be a pressure loss (water egress through Inlet, outlet or case; or and air leak in the accumulator/bladder), it could also be something triggering the sensor electrics.

 

A step-by-step test and examination of the pump should reveal the cause. 

 

 

5 minutes ago, bankruatsteve said:

10 minutes ago, AtlasAus said:

It ended up being a "flapper" valve type thing on the inlet line,

Was that the inlet line from the meter?  Was it a "check valve" (NRV)?

This would be what I'd suspect, if I couldn't find a active water leak or air leak of the accumulator/bladder (if the pump has one).

[Fruit Trader]

1 hour ago, Davejf2017 said:

I had valves closed on inlet and outlet of pump while i was changing a tap as thought tap was leaking and heard pump start up for few seconds then stop.

You have not included make and model of pump.

If the pump isolation valves are healthy and the pump continues to cycle at regular intervals when they are closed, inspect the pump and its components for leaks.

 

Common places for leaks around a house pump are pressure tank seams and mechanical seal between pump and motor.

Edited May 20, 2020 by Fruit Trader

[VocalNeal]

1 hour ago, RichCor said:

As the pressure sensor is usually a electro/mechanical device it will have a wet and a dry side.

 

With the wet side being the sensor section and the dry side being the switch section. As you said ants have got into the sensor section, it is wet. If the ants are in the dry section they are inside the switch.

 

 

[Andrew Dwyer]

When i did similar checks for my leak, closing the stop valve just before my pump ( it has to be between the pump and tank ) the pump cycled but as was unable to draw water in it vibrated heavily and didn’t stop cycling until I stopped it ( basically trying to draw water and achieve the desired pressure but unable) similar to if you run out of water in your tank.

 

The OP says his pump cycled with both valves, before and after pump, closed.

I suspect the pressure switch.

Or ,as Arjen stated, the stop valves are not closing fully.

 

 

 

Edited May 20, 2020 by Andrew Dwyer

[RichCor]

29 minutes ago, VocalNeal said:

With the wet side being the sensor section and the dry side being the switch section. As you said ants have got into the sensor section, it is wet. If the ants are in the dry section they are inside the switch.

You usually aren't this weird. Is everything OK with you?

 

 

[Davejf2017]

8 hours ago, Fruit Trader said:

You have not included make and model of pump.

If the pump isolation valves are healthy and the pump continues to cycle at regular intervals when they are closed, inspect the pump and its components for leaks.

 

Common places for leaks around a house pump are pressure tank seams and mechanical seal between pump and motor.

The pump is a Mitsubishi which is sited just after a 2000 litre free standing water tank the mains water goes into the tank first then into the water pump.The pump turns itself on when a tap or shower is turned on.I have taken the cover off the pump there are no leaks.Pump still turning itself on every 20 minutes.Do you think there is a fault with the pump.

[Andrew Dwyer]

1 hour ago, Davejf2017 said:

The pump is a Mitsubishi which is sited just after a 2000 litre free standing water tank the mains water goes into the tank first then into the water pump.The pump turns itself on when a tap or shower is turned on.I have taken the cover off the pump there are no leaks.Pump still turning itself on every 20 minutes.Do you think there is a fault with the pump.

Check your stop valve on the output by closing it and opening a tap in the house, if the pump kicks in then the stop valve is not closing completely.

If the pump doesn’t start then the good news is that you don’t have a leak in the pump but more than likely have one in the pvc, a dripping tap or overflowing toilet etc.

Check the stop valve on the input is not as simple but with it closed and the pump is still cycling for a second or two but then stops it could be faulty/slightly open, but would then mean that the non return valve built into the pump ( if fitted ) is also allowing water backwards into the tank, which I think unlikely unless your tank is underground.

With the input stop valve ( healthy ) closed your pump should vibrate loudly and continue to run trying to suck water until you open the stop valve or turn off the pump.

 

Think of it this way:

When you put power to your pump it runs to obtain pressure between, for example, 20 and 26 psi ( on my Hitachi ) with all the outlets ( taps , showers etc ) closed the pump will sit waiting and the pvc pipework will be pressurised within the pressure range.

Open a tap, the pressure in pipes drops below 20 psi and enables the pump, close a tap the pressure increases to above 26 psi and the pump stops.

What is happening to you now is ; the pressure is dropping very slowly and the pump kicks in to regain pressure.

This is usually a sign of a leak either in the pump itself, a dripping tap or shower, an overflowing toilet or a pvc pipe joint is badly glued and allowing water to seep out.

 

You need to identify if the leak is occurring in the pump or after the pump.

 

If the pump is cycling regularly every 20 minutes it points to a leak and not the pressure switch as I stated earlier.

 

My leak cycled the pump every 2 hours initially but increased in regularity to every 30 seconds.

 

Edited May 20, 2020 by Andrew Dwyer

[Crossy]

20 hours ago, Davejf2017 said:

I had valves closed on inlet and outlet of pump while i was changing a tap as thought tap was leaking and heard pump start up for few seconds then stop.

 

Have you performed the checks in Post #2, result?

 

The reasoning.

If the pump stops cycling with the outlet valve closed the you likely have a dripping toilet / tap or leak in your plumbing.

If the pump stops cycling with the inlet valve closed then it'l likely the non-return valve on the pump inlet (often built in to the pump itself).

 

Now you know where to concentrate your efforts.

[Don Mega]

My mitsu pump was cycling due to a leaking inlet pipe.

 

sorted that and now it no longer cycles.

 

I dont have a valve to close on the inlet though if that makes any difference.

 

https://forum.thaivisa.com/topic/1159231-water-pump-repair-or-replace/

Edited May 20, 2020 by Don Mega

[Davejf2017]

10 hours ago, Andrew Dwyer said:

Check your stop valve on the output by closing it and opening a tap in the house, if the pump kicks in then the stop valve is not closing completely.

If the pump doesn’t start then the good news is that you don’t have a leak in the pump but more than likely have one in the pvc, a dripping tap or overflowing toilet etc.

Check the stop valve on the input is not as simple but with it closed and the pump is still cycling for a second or two but then stops it could be faulty/slightly open, but would then mean that the non return valve built into the pump ( if fitted ) is also allowing water backwards into the tank, which I think unlikely unless your tank is underground.

With the input stop valve ( healthy ) closed your pump should vibrate loudly and continue to run trying to suck water until you open the stop valve or turn off the pump.

 

Think of it this way:

When you put power to your pump it runs to obtain pressure between, for example, 20 and 26 psi ( on my Hitachi ) with all the outlets ( taps , showers etc ) closed the pump will sit waiting and the pvc pipework will be pressurised within the pressure range.

Open a tap, the pressure in pipes drops below 20 psi and enables the pump, close a tap the pressure increases to above 26 psi and the pump stops.

What is happening to you now is ; the pressure is dropping very slowly and the pump kicks in to regain pressure.

This is usually a sign of a leak either in the pump itself, a dripping tap or shower, an overflowing toilet or a pvc pipe joint is badly glued and allowing water to seep out.

 

You need to identify if the leak is occurring in the pump or after the pump.

 

If the pump is cycling regularly every 20 minutes it points to a leak and not the pressure switch as I stated earlier.

 

My leak cycled the pump every 2 hours initially but increased in regularity to every 30 seconds.

 

When I turned the valve on outlet side off with inlet valve open then opened a tap pump starts then stops then starts then stops keeps doing this.

[Andrew Dwyer]

59 minutes ago, Davejf2017 said:

When I turned the valve on outlet side off with inlet valve open then opened a tap pump starts then stops then starts then stops keeps doing this.

If the stop/start/stop/start is rapid then it means the valve is not closing fully ( this would explain why the pump cycled when you had both closed to replace a tap ) and kinda complicates the troubleshooting if you can add another stop valve close by ( easier than replacing ) would be ideal.

This won’t cure your intermittent pump cycling but will help to understand the issue.

 

My water leak was easily diagnosed as closing the valve on outlet of pump stopped the intermittent cycling completely and enabled me to search for the leak in pvc , toilets etc

Edited May 21, 2020 by Andrew Dwyer