#  >  > Living And Legal Affairs In Thailand >  >  > Construction in Thailand >  >  Hitachi water pump - help please

## benbaaa

I have an automatic water pump (Hitachi GP Series WT-P 250GP) which pumps water from my tank to my taps when I turn them on.  It's less than a year old, but recently, I have noticed it running when there are no water taps on in our house.  It sound like the pump is trying to pump air and water instead of water.  

I checked the water tank first, and it's full of clean water, with no obstruction in the pipe which goes to the pump.

I removed the plastic cover and unscrewed the cap on top (pictured with my fat finger pointing at it), and there was a hiss of escaping gas.  I poured water in the hole - Mrs benbaaa said this was the thing to do - until it was full, then screwed the cap on again.  This seemed to fix the problem for a while, but now I get the sound of water and air being pumped again.  Any advice?

This is my pump.


This is the cap I unscrewed.


Cheers,

bb

----------


## Thetyim

Switch the electric off
Drain the pump reservoir
Switch it back on

This will  reset the air volume in the reservoir to the correct level

----------


## BobR

I disassembled the shut off mechanism on mine and found it jammed with green algae.  I cleaned it with a tooth brush, and it worked for about 4 months, then it started running all the time because it was full of algae again.  The Toshiba is a good pump, but the water here is filthy.  

Think of that the next time you brush your teeth.

----------


## jandajoy

Benbaa,  we had a similar thing happen. Went on for ages. We'd open the cap, as you did and fill it up and it'd be fine for a while then start over again.

Then, to my shame the bloke next door came round and made a slight adjustment to a screw on the top of the pump under the cover. It'd been good for months now.

Our pump is not a Hitachi, its some Chinese cheapo but you might have such an adjusting screw on yours.  Just a thought.


By the way, here's a manual from Hitachi

http://www.hitachiconsumer.com.my/ho.../WT-P400GP.pdf

----------


## FarangRed

Also check for leaking pipes

----------


## kingwilly

Have you contacted Driving Force, I heard that he's an exert on pumps.

----------


## Thetyim

Ben, I wouldn't spend time worrying about the pump I would concentrate on finding where your left thumb went.

----------


## Norton

Is your tank is below ground?

If so the check valve in the water pump may not be working properly, allowing water to run back into the tank leaving air in the impeller.  Remove the plastic cap your fat finger is pointing at.  You will see a plunger like plastic valve with a spring.  Pull it out and check to see if the rubber gasket and where it seats is clean.  Also, make sure the spring is functioning.

----------


## nedwalk

clean yer fingernails..

----------


## benbaaa

> Switch the electric off 
> Drain the pump reservoir 
> Switch it back on


Could you give a few details about draining the pump reservoir? Like where is it, what is it and how to drain it? Please.  :Very Happy: 

JJ thanks for the manual - I couldn't find one.




> Is your tank is below ground?


I'm not very technically minded, Norts, but I think my tank is the large aluminium thing full of water behind the pump in the first picture.  :La:

----------


## benbaaa

> JJ thanks for the manual - I couldn't find one.


D'oh!  That's not a manual.  It doesn't tell you anything about routine maintenance or what to do if it goes wrong.  :Sad:

----------


## Norton

> I'm not very technically minded, Norts, but I think my tank is the large aluminium thing full of water behind the pump in the first picture.


Should have noticed in the pic.  My apologies.  Above ground so not likely  a check valve problem.

Try this.



> Switch the electric off Drain the pump reservoir Switch it back on  This will reset the air volume in the reservoir to the correct level



If it doesn't work, try this.




> Also check for leaking pipes


The pipes between your tank and the pump.  Turn off the pump and see if any water is leaking.  If you see water leak then when the pump is turned on the leaking bit will be sucking air into the pump.

----------


## jandajoy

> D'oh! That's not a manual. It doesn't tell you anything about routine maintenance or what to do if it goes wrong.


Shows you how it works though don't it.

Try this;

http://www.inspectapedia.com/water/W...termittent.htm

----------


## benbaaa

> Should have noticed in the pic. My apologies.


You're so polite.  :Smile: 

Waiting for Thetty to get back to me about draining the pump reservoir, as I have a knack of really fokking things up when I try to work out how to do stuff myself.

JJ, thanks for that link:




> Here are the more likely causes of the water pump coming on at odd  times when you're not (aware of) running any water. You may want to  investigate these possible causes roughly in the order they are listed below.
> *Running Toilets*: A toilet somewhere in  the building is running - this can be VERY hard to spot - unless you are  meticulous. I've tried wiping the toilet bowl interior to make it dry  and then feeling it later for wetness above the water line, or watching  the water in the toilet bowl for ripples, or placing a little septic dye  or food coloring in the toilet tank to see if it appears in the bowl  below, or, simplest, simply turning off all toilets at their supply  valve to see if the pump cycling goes away. A leaky flush valve or a  leaky fill valve in a toilet causes this problem.*Leaky Plumbing Fixtures*: A plumbing fixture  such as a sink, tub, shower, or clothes washer is leaking slowly -  dripping into the fixture (where you can see it) or worse, dripping into  a hidden building cavity such as a wall or ceiling cavity (where water  stains eventually show up below) or into a floor or crawl space (where  you may not see the leak).*Leaking Water Tanks*: An air leak at the  water pressure tank, above the water line in the tank, (or a water leak  from the water pressure tank) can cause the tank to slowly lose air and  the water pump to cycle on. This is possible with both traditional steel  water tanks and with modern captive-air bladder type tanks (water is in  a separate bladder inside the tank). Older water tanks which have an  air volume control (which rarely work) are designed to automagically add  air to the water tank as needed, so if the AVC is working and if there  is a little air leak on the tank somewhere (often you can spot a rusty  pinhole leak), this condition could continue for a while before being  diagnosed.*Leaky check valve or foot valve*: A check  valve at the pump or a foot valve in the well at the bottom of the water  pipe could be failing and leaking, sending water backwards from the  pressure tank, through the water pump, and back into the well. This can  eventually lead to loss of prime and loss of all water supply as is  discussed at our website.*Leaks in well piping*: A water leak in the  well piping between the building and the well or even inside the well  could also cause a back-flow of water from building to well and lead to  pump cycling on and off.*Defective Pressure Control Switch*: A  defective pump pressure control might, in theory cause this intermittent  cycling but in more than 30 years of practice I've not found this to  occur.*To Fix Water Pump Intermittent Cycling*
> 
>  To correct the problem of water pumps coming on when there is no  apparent reason, we need to find which of the causes listed above is occurring. Remember that on occasion more than one fault could  be present. Each of the possible causes listed above is also discussed as a diagnosis and repair topic at this website. Use  the links at page left or the "Search Box" on any of our web pages to look for further advice.



Pretty sure that 1 and 2 aren't what's causing it. The pump still runs when all the water taps are off and all supply valves are off.  I guess there could be a leak underground or behind a wall, but there's no evidence, so how could I find out?


3 is N/A 'cos it's not a pressurized water tank. Not sure I completely understand what 4 or 5 are all about.  6 sounds like your slight adjustment to a screw.  After I've tried Thetty's suggestion, maybe I'll get the shop guy to come and have a look.  As I said, it's less than a year since it was installed.

----------


## jandajoy

> I'll get the shop guy to come and have a look. As I said, it's less than a year since it was installed.


By far the best plan.

----------


## Thetyim

> Waiting for Thetty to get back to me about draining the pump reservoir


Turn off the electric
Shut the red gate valve water supply from the tank. I can see it in the photo above.
Open a tap in the house to relieve water pressure.
Remove a plug from the reservoir. I can't see the plug in the photo. It will probably be 90 degrees from the house supply pipe.  (facing the water tank)
Let the water drain out then reverse all the things you did above to get back to normal.

----------


## DrAndy

> I'm not very technically minded, Norts, but I think my tank is the large aluminium thing full of water behind the pump in the first picture.


it is probably stainless steel, but never mind

and if it is less than a year old and they installed it, call them back to fix it

even if they didnt install it

----------


## benbaaa

Gonna try Thetty's suggestion.  Breakfast first, though.

----------


## Butterfly

could be the same problem I had, it was the "pressure valve" if I remember correctly, it was broken and would go into an endless cycle

eventually the "small reservoir" started to melt because the water was too hot

----------


## FarangRed

it should cut out there Butters, joking apart it's sometimes difficult to tell you whats wrong without seeing it, one thing that does happen is the foot valve at the bottom of the pipe in the well I'm afraid they dont last long and stick open causing the water to go back down in the well, just get the guy who installed it to take a look

----------


## RamboII

Is there a water pump sold in Thailand that is demonstratively better than the rest, as far as reliability?   I need to replace the pump running my underground lawn sprinklers (4 zones with 4 sprinkler heads on each zone) and eventually the pump for my house (3 bathrooms and two kitchens).  From what I've read, hitachi and Grundfos are both good pumps, with Grundfos being more reliable and more expensive.  I need reliable because I am away from Thailand most of the time and need my grounds watered regularly.

----------


## pickel

> could be the same problem I had, it was the "pressure valve" if I remember correctly, it was broken and would go into an endless cycle  eventually the "small reservoir" started to melt because the water was too hot


I had the same problem and solution. Things get sticky in humid environments and the pressure valve won't release as easy as the day you bought it.

----------


## Butterfly

> Is there a water pump sold in Thailand that is demonstratively better than the rest, as far as reliability?


I have been told many times that HITACHI were crap, and they broke down quite easily, could be unfounded rumors though

it seems that everyone is swearing with FUJIKA, a bit more expensive but should last longer

----------


## jandajoy

> I have been told many times that HITACHI were crap, and they broke down quite easily, could be unfounded rumors though  it seems that everyone is swearing with FUJIKA, a bit more expensive but should last longer




 :smiley laughing: Your English is hysterical.

----------


## RamboII

Looks like it is going to be a Grundfos.

----------


## FarangRed

> Is there a water pump sold in Thailand that is demonstratively better than the rest, as far as reliability?   I need to replace the pump running my underground lawn sprinklers (4 zones with 4 sprinkler heads on each zone) and eventually the pump for my house (3 bathrooms and two kitchens).  From what I've read, hitachi and Grundfos are both good pumps, with Grundfos being more reliable and more expensive.  I need reliable because I am away from Thailand most of the time and need my grounds watered regularly.


I have 2 Grundfos on my sprikler system they have been there for 5 years now and turn on twice a day, no problem so far

----------


## benbaaa

Well, I did Thetty's thing - back on page 1 before the thread hijack  :Sad:  - I found a panel labelled *out* at 90 degrees to the water inlet and took it off, drained the water (having previously cut off the power, turned on a tap and turned off the supply from the tank first).  Then I reversed everything and the pump started up.  It was fine for a day, but now I still get this kind of sputtering noise when it's working, like there's air where it shouldn't be inside the pump.  The pump's only coming on when it should, but it doesn't sound right.  It used to be a quiet, high-pitched whine.  Now it's the whine plus sputtering.

----------


## Marmite the Dog

^ Maybe got a leak and the air is exiting its reservoir? Get the bloke in the shop to take a look before you do a Butterfly on it.

----------


## VocalNeal

When you run the water in the house out of the tap/faucet do you get 100% water or do you get any air sputtering.

----------


## benbaaa

^ Just water, as normal.  No sputtering.

----------


## FarangRed

Have you not fixed that fuking pump yet?

----------


## benbaaa

Several times.  :Sad:

----------


## VocalNeal

My original thought was that you were getting air sucked in on the suction side but waited until you had done the Thetty fix. 

If there is no sputtering when the water is running then the system is full of water. Is the tank below ground or can you check if the water free flows from the tank?

I wouldn't worry too much about the sputtering noise. Unless it interferes with daily life.

First question for trouble shooting is " What has changed?" Only you can answer that.

----------


## Thetyim

> It was fine for a day, but now I still get this kind of sputtering noise when it's working


That would suggest that we are in the right area (amount of air in the reservoir)
Need to now find out why the reservoir is losing/gaining air.

Top left of your picture shows three screws.
In there is a diaphragm that controls the pressure going to the pressure switch.
This sometimes gets dirt in it.
Problem is the housing is plastic so retightening the screws correctly is critical and the black plastic tube must remain airtight.
If you ain't confident then get a thai expert to look at it and he will fuck it up for you.

----------


## benbaaa

> If you ain't confident then get a thai expert to look at it and he will fuck it up for you.


I got as far as the word *expert* and thought to myself _fer fok's sake Thetty, you've lost it_.  But then I read the rest of the sentence.  :Very Happy:

----------


## VocalNeal

I have had a Sanyo pump in Indo. and now a Mitsubishi. I cannot find anything in the way of instruction or fault finding.

One thing I did find was on Yahoo answers  they speculate on a vortex in the water tank. 

It may be worth turning on a couple of taps in the house then looking inside the water tank while the pump is running to see if this is the case. An outside chance as it was not happening before but.....

I trust you have a sufficient quantity or beer while attempting all this work.

----------


## benbaaa

> It may be worth turning on a couple of taps in the house then looking inside the water tank while the pump is running to see if this is the case. An outside chance as it was not happening before but.....


Nothing to see inside the tank when the taps are on.  Just slowly decreasing water level.

My beer-drinking days are long gone.  :Sad:

----------


## Butterfly

^ why aren't you calling the installer ? or the shop you bought it from ? something is obviously broken, I am sure it can be fixed for less than 1000 THB

----------


## FarangRed

Get the Thai expert in be done in 2 minutes

----------


## Marmite the Dog

> My beer-drinking days are long gone.


Really? You're going to be a bundle of laughs at the weekend, then.

----------


## FarangRed

Have you still got the box that the pump came in?

----------


## benbaaa

> Originally Posted by benbaaa
> 
> My beer-drinking days are long gone.
> 
> 
> Really? You're going to be a bundle of laughs at the weekend, then.


Yes.




> Have you still got the box that the pump came  in?


No.

----------


## lom

> ^ why aren't you calling the installer ? or the shop you bought it from ? something is obviously broken, I am sure it can be fixed for less than 1000 THB


Isn't that the advice you are usually given by others here?  :mid:

----------


## Butterfly

^ indeed, and I follow them  :Razz:

----------


## Norton

> indeed, and I follow them


We've had lots of "My water pump is broken" threads.  Trying to fix a problem on a forum is near impossible.  Way too many possible fixes on something that has all sorts of interdependent parts.

Unless it's something obvious, always better to have a fix it guy do the job.

If you don't, result will be getting an unwanted shower and a flooded house. :Smile:

----------


## benbaaa

> better to have a fix it guy do the job.


We have had some bad experiences with fix it guys.  

One guy couldn't be bothered to screw a set of hinges into the door frame - he used a fucking hammer to put the screws in.  

Another guy blew himself off the ladder because he said he didn't need me to cut the power before he changed an electrical fitting.  

Another guy had two new doors to fit to our bathrooms.  One _big door_ for the _big doorway_ and one _small door_ for the _small doorway_.  I was at work, and Mrs bb wasn't paying attention.  First thing he did was cut the _big door_ to fit the _small doorway_.  Then he complained that the _small door_ was too small for the _big doorway_.  We chucked him out without paying him.

 :Sad:

----------


## Norton

> We have had some bad experiences with fix it guys.


Haven't we all.  Contact Hitachi.  They will steer you to a proper service guy.

Email - pip[at]has.hitachi.co.th

Phone - +66  (2) 632 9292

The pump may well be under warranty so might get lucky with little or no charge.

----------


## Butterfly

> We have had some bad experiences with fix it guys.


I know how you feel, but installers should be different ? or didn't they do a good job installing the pump ?

----------


## benbaaa

> Haven't we all. Contact Hitachi. They will steer you to a proper service guy.  Email - pip[at]has.hitachi.co.th  Phone - +66 (2) 632 9292  The pump may well be under warranty so might get lucky with little or no charge.


That's probably the way to go.




> I know how you feel, but installers should be different ? or didn't they do a good job installing the pump ?


The guy who did the big and small doors installed the pump.  :Sad:

----------


## jandajoy

> The guy who did the big and small doors installed the pump


Sorry mate but



 :smiley laughing:  :smiley laughing:  :smiley laughing:  :smiley laughing:  :smiley laughing:

----------


## Butterfly

> The guy who did the big and small doors installed the pump.


oops, call the manufacturer then, that's what I did, and they sent me a good guy

----------


## FarangRed

I think you have 5 years warranty on that pump

----------


## benbaaa

I think so too.  Next job is to find the receipt.

----------


## Norton

> Next job is to find the receipt.


Even if you do, if the problem is not the pump but the installation, Hitachi's guy will get it sorted but will charge for fixing installation problems.

----------


## Thetyim

> Hitachi's guy will get it sorted but will charge for fixing installation problems.


True, but at least it will be fixed.

Try asking the Hitachi guy if he can report it as a gaurantee repair and then you pay him cash  :mid:

----------


## benbaaa

I don't think it's an installation error, despite Mr Fuckwit who installed it.  The pump ran smoothly and silently for at least seven months.  It's only in the last couple of weeks we've had this sputtering noise.

----------


## Norton

> It's only in the last couple of weeks we've had this sputtering noise.


If as you say, pressure at faucets is OK and no air is coming out, sputtering noise may not be air as we assumed.  Could be pump impeller noise caused by any number of things.  Hitachi guy will get it sorted.

----------


## benbaaa

> Next job is to find the receipt.


Hmmm.  I seem to have every receipt for everything I've bought since 2001.  Except for one.  :Sad: 

Search continues.

----------


## the dogcatcher

I had the same prob.
Turned out there was a bit of plastic bag in the impeller.

----------


## benbaaa

> impeller


WTF is that?

----------


## Norton

> WTF is that?


The bit that looks like a fan blade driven by the motor.  Sucks the water in and pumps it out.  On your pump it's inside the brass casing.  If there's air, plastic, sand, or other bits in there you will hear a shushing noise.

----------


## the dogcatcher

Ok.
Lift the lid of the pump.
As Naughty says on the side of the pump there will be a round plate secured by 4 stainless steel bolts.
This is probably the only bit of the pump that isn't painted grey, the plate will almost certainly be round.
If you can isolate the pump from the tank then do so, if you can't your going to get wet.
Remove that plate to reveal the impeller.
It looks like a fan with about 100 blades.
Check carefully visually between each blade, I bet you find plastic bag fragments.
Do of course unplug the pump before you do this
Good luck.

----------


## Norton

^Good instructions but I think in this case, call the Hitachi guy!

No offense to your skills Benbaaa. :Wink:

----------


## benbaaa

> No offense to your skills Benbaaa.


Cheeky bugger.  I've got a hammer, you know.  Still looking for the receipt.

----------


## Norton

> I've got a hammer, you know. Still looking for the receipt.


A hammer and a receipt.  No worries mate.  She'll be right.

----------


## the dogcatcher

When you say it runs without taps turned on do you mean all the time.
It's quite normal for a pump to trigger occationally with no taps on.
No system is completely air tight.

----------


## Thetyim

> Still looking for the receipt.


Maybe it's jammed in the impeller

----------


## benbaaa

^ Fok off.   :Very Happy: 

^^ No, just occasionally, but it seems more often than usual.

----------


## the dogcatcher

You have a slight leak somewhere or the peasants are'nt turning the taps off all the way.
Actually you can see the impeller cover under you hand in the pic.
Yours appears to have 5 bolts, and as suspected isn't painted grey.

----------


## the dogcatcher

The rustling noise could also be the pump on the cusp of turning off.
If a tap is just on then the pump will fire, and just before it clicks off will create a rustling noise. Mine does this but it's rare.
I have an HP 130.

----------


## FarangRed

you are not fit to own a fuking pump

----------


## jandajoy

13.00 on the 25th. = first post. 

It's now 20.12 on the evening of the 3rd.


And you still haven't called a bloke in to fix it.


This beginning to smell.....

----------


## the dogcatcher

> you are not fit to own a fuking pump


 
I,ve got a fucking pump.
It's completely automatic and makes a sort of squelching noise when I use it.

----------


## globin

> I have an automatic water pump (Hitachi GP Series WT-P 250GP) which pumps water from my tank to my taps when I turn them on.  It's less than a year old, but recently, I have noticed it running when there are no water taps on in our house.  It sound like the pump is trying to pump air and water instead of water.  
> 
> I checked the water tank first, and it's full of clean water, with no obstruction in the pipe which goes to the pump.
> 
> I removed the plastic cover and unscrewed the cap on top (pictured with my fat finger pointing at it), and there was a hiss of escaping gas.  I poured water in the hole - Mrs benbaaa said this was the thing to do - until it was full, then screwed the cap on again.  This seemed to fix the problem for a while, but now I get the sound of water and air being pumped again.  Any advice?
> 
> This is my pump.
> 
> 
> ...


The non return valve is located under the cap with three screws just beside or behind the priming plug hole.  I have often found debris under this valve which will cause frequent pump cycling.

----------


## Auroria

Hope that fixes it. The washing up will have built up a bit over the last 6 years.

----------


## crippen

stripped my pump down a while ago.doing a lot of strange things.    Cleaned it all out,lots of gunge inside the various ports.  And the impeller inside the brass casing was loose on the shaft.   It is only held in place by 4 centre punch marks !!!!!!! Punch these a bit harder,gently though.  All ok now.   :bananaman:

----------


## globin

> Hope that fixes it. The washing up will have built up a bit over the last 6 years.


Haven't you noticed we run in a different sort of time here? :>)

----------

