Plumber needed to locate & repair water leak

[jeffandgop]

I live in Chiang Mai (San Piseua) and need a plumber to locate/repair an apparent water leak.  My pump cycles on and off about every 4 minutes running about 30 seconds.  I have checked and re-checked inside the home for any leaking toilets, water lines, valves, etc. and no issues there.  I have crawled under my house and not have seen any leaks but it is a difficult area to see clearly and the leak is very small I suspect.  Anyone have experience with a professional competent tradesman?
Thank you.

Jeff

Edited March 22, 2020 by jeffandgop

[Crossy]

It could be the pump inlet non-return valve leaking pressure back to the tank (we had a similar problem, you could just hear the valve burbling when the pump was stopped).

 

Does your pump have a shut-off valve on the outlet? Does closing it stop the cycling?

[saengd]

Pump cycling is often caused by a leaky bladder valve on the pump unit. The way to check is to isolate the pump electrics by turning off the breaker at the consumer unit, turn off the water supply to the pump and then remove the pump cover. The bladder valve is a dome like object that is quite large and unscrews from the pump body. The bladder valve contains a rubber bladder and is filled full of gas, as the bladder ages the gas escapes and it causes pump cycling. Unscrew the unit and take a pencil and insert it into the bladder valve and see if it goes in a long way or a short way, if a short way, the bladder is still full of gas and your problem is elsewhere, if it goes in a long way the gas has escaped and the unit must be replaced - Home Pro or similar, 1,000 baht ish.

[jeffandgop]

43 minutes ago, Crossy said:

It could be the pump inlet non-return valve leaking pressure back to the tank (we had a similar problem, you could just hear the valve burbling when the pump was stopped).

 

Does your pump have a shut-off valve on the outlet? Does closing it stop the cycling?

Hi Crossy!  I don't have a non return valve between the tank and the pump.  I do have a shut off valve I can close downstream from the pump and yes, when closing that valve it does stop running. I keep this valve closed now unless I need to do laundry or shower as I have a bypass that I open that provides water without going thru the pump but the pressure is very poor.  This added pic shows the run of water from the tank to the pump and the blue shutoff valve post pump.

 

Edited March 22, 2020 by jeffandgop

[jeffandgop]

Saengd- Thanks for your input...my pump is less than a year old and is Hitachi Inverter Model WM-P400XV- a very high quality unit.  Do you think the bladder could actually lose gas in less than a year?  I had another Hitachi pump that had no problem for the 5 years that it ran before this current one...what do you think?

[jeffandgop]

BTW- About 6 months ago I suffered a similar problem...After 3 days of crawling under the house and installing cutoff valves in the water lines feeding the house, a pin hole leak to an outdoor shower (the farthest point away from the pump)  was finally identified and repaired....I fear that a pin hole leak somewhere in the line is the culprit...

Edited March 22, 2020 by jeffandgop

[saengd]

It seems very improbable that the unit would fail in under one year, ours failed after 5 years. Nevertheless, store the idea in the back of your mind and if you can find no other solution or cause, it only takes five minutes to check.

[saengd]

1 minute ago, jeffandgop said:

BTW- About 6 months ago I suffered a similar problem...After 3 days of crawling under the house and installing cutoff valves in the plumbing lines feeding the house a pin hole leak to an outdoor shower was finally identified and repaired....I fear that a pin hole leak somewhere in the line is the culprit...

That would be my guess also, especially since you said that turning off the downstream valve cause the problem to go away. Get under that house my lad and start looking, again.

[jeffandgop]

27 minutes ago, saengd said:

That would be my guess also, especially since you said that turning off the downstream valve cause the problem to go away. Get under that house my lad and start looking, again.

I've looked already and could not find myself...that's why I'm asking/needing plumber person recommendation...

 

[Crossy]

56 minutes ago, jeffandgop said:

 I don't have a non return valve between the tank and the pump.

 

It's built in to the pump, but since your downstream valve stops the cycling that's not the issue anyway.

 

If you've already got isolation valves from your previous issues, time to start closing them. At least then when you find a plumber you can point him the right way.

 

[Swiss1960]

I sympathise with you,  I had the exact same problem 4 months ago.  Cycling went from 2.5 minutes to 60 seconds and water bill doubled.

 

From what I read, you say that if you cut off the water to the house, the pump stops cycling,  so the problem is NOT the pump whatever people tell you. I had the exact same situation on tried a replacement pump without success.

 

You say you can switch off the pump and use the bypass. Does your meter still run (very slow but nevertheless), then you have a leak. I had the exact same problem.

 

After 2 months of consulting every possible "authority", getting quotes from 

- 8'000 Baht to come for check and consult to

- 50'000 Baht for new water lines

 

I found a Thai guy who put NEW water lines AROUND the house from the government inlet to the 2 bath and kitchen, replaced the minimum of tiles he had to break inside the rooms (luckily  i could find all the same) and around the house (both hot and cold water lines) for 5'000 Baht labour cost for 6 days work. I bought all the material needed, around 3'000 Baht in total. He fixed it in a way that every evening, at least one shower was working. 

 

Finding a small leak which can be inside the walls is almost impossible in Thailand, nobody seems to have the equipment needed to do that. By replacing all piping, you can additionally add strategic stops to in future cut off room by room and also flow back controls and design the bypass to be better. My guy worked based on MY plans, took him a while to understand and accept what I wanted.  

[jeffandgop]

1 hour ago, Crossy said:

 

It's built in to the pump, but since your downstream valve stops the cycling that's not the issue anyway.

 

If you've already got isolation valves from your previous issues, time to start closing them. At least then when you find a plumber you can point him the right way.

 

I feared as much...thanks for the quick response and advice.....God I just hope it's not leaking in a few runs that are under concrete!!

[Andrew Dwyer]

I have exactly the same issue, the pump started cycling, at first hourly then more frequently, it is currently every 5 minutes now. We turn off the pump at night now and when we go out.

 

I did post a thread on here , like yours, to identify the problem and can confirm that closing the stop valve after the pump ( stopping the cycling ) does eliminate a pump problem, if the cycling stops with the valve closed then the bladder is okay and retaining pressure.

In fact i closed a valve before the pump also to check the built in non return valve ( don’t stray too far if you do this test as the cycling will try to draw water from your tank and with the stop tap closed heavy vibration will occur, similar to if you run out of water ).

 

If you have any doubt that the leak might be in your toilet ( sometimes difficult to detect ) put food colouring ( or those blue blocks ) in the cistern and leave for a few hours, the leak will be obvious.

 

I dug up tiles and concrete in several places where I thought the leak was likely to be , but no !!, the leak is underneath the house or in a wall somewhere.

 

Am now in the process of replacing all the pvc pipework from the pump to 13 points ( 3 bathrooms + 1 kitchen ) inside the house and 5 points outside.

 

A daunting task indeed but it does seem common for a joint to fail ( poorly glued or even no glue ! ), i am tackling the job myself ( as i’m OCD  ???? ) so will probably take a while.

 

Good luck

[Dante99]

1 hour ago, Andrew Dwyer said:

Am now in the process of replacing all the pvc pipework from the pump to 13 points ( 3 bathrooms + 1 kitchen ) inside the house and 5 points outside.

 

Was/Is it not possible to put a couple of valves in to isolate the inside from the outside to determine which has/had the leak?

 

You may find such valves plus a few more useful in the future to isolate various parts of the system for repair or evaluation.

[Andrew Dwyer]

8 minutes ago, Dante99 said:

Was/Is it not possible to put a couple of valves in to isolate the inside from the outside to determine which has/had the leak?

 

You may find such valves plus a few more useful in the future to isolate various parts of the system for repair or evaluation.

Yes, after checking a couple of areas outside under tile and concrete walkway that I suspected I uncovered the pipe as it went under the house, cut the pipe and capped, then tested from the pump to capped end, all good no cycling so leak is in the abyss.

The floor of my house is 35 cm above the incoming pipe, probably 15cm slab and the rest soil,  so the chance of water appearing at floor level unlikely, no signs of any leaks from bathroom/kitchen walls either so i have no choice.

 

Of course repiping the whole thing means i can put in stop valves at regular intervals, also threaded straight connectors to enable any future changes.

 

From my previous thread something mentioned putting in a gauge after the pump also to help troubleshooting .

 

[tpiety2]

Bleed the pump.