Page 1 of 2 12 LastLast
Results 1 to 25 of 38
  1. #1
    Newbie
    Join Date
    Apr 2011
    Last Online
    23-02-2017 @ 06:48 PM
    Location
    Sattahip
    Posts
    17

    Reduced power from Mitsubishi water pump

    Hi,

    Hopefully I've got the right forum. Apologies if not. I've got a typical 1 story house setup. Water tank, water pump with a self contained pressure tank on the bottom. I replaced a Hitachi 150 W pump with a Mitsubishi WP 155Q5. The pressure is low - maybe 70% of the Hitachi. The contractor seemed to know what he was doing but I'd like to check myself. He spent some time with the instruction sheet, showed me a spring that he said was better left out - seemed to indicate to only use it if I was pumping from a well, and I saw him making some adjustments with a screwdriver but could not see exactly where.

    I'd like confirmation on the spring thing, info on how to check the pressure adjustment, and of course any other constructive ideas.

    Thanks.

  2. #2
    Thailand Expat
    crepitas's Avatar
    Join Date
    Apr 2013
    Last Online
    27-03-2017 @ 08:11 AM
    Posts
    1,965
    555..this should be good...

  3. #3
    Sukhumvet
    VocalNeal's Avatar
    Join Date
    Jul 2007
    Last Online
    Today @ 10:10 AM
    Location
    Bangkok
    Posts
    9,781
    The contractor is a twat. Why feck with anything?

    Double check the valve at your water meter is fully open.

    I suspect the spring he removed is the nor return valve. Useful if you are in a multistory house as it stops the water on the upper floors flowing back into the pump. If you still have it, put it back in.

    The adjustment he made is likely the pressure switch setting which is probably where the pressure difference is. I don't know how much he backed it off.
    It is under the small cylindrical cover on the top of the tank to the side of the actual pump with a cable coming out . The cover is secured by a single small screw. Under it is the screw in question. Give it half a turn clockwise and try the water, if not the same give it another 1/4 turn. There will be , in theory, some red paint on it to indicate where it was set at the factory. When pressure is where it was with your Hitachi line the paint up. Don't be greedy!

    Spec wise there is not much between the pumps. Pressure should be between 12 and 18 meters of water. Flow rate around 30l/min for the garden hose and a bit less for the shower.

    Did the guy use the same diameter of pipe for the replacement or did he use smaller pipe and bends and valves and stuff.

    If you don't know which end of a screw driver to use call the guy back.
    Last edited by VocalNeal; 26-12-2016 at 10:11 AM. Reason: Sorry read Sattahip and thought Satuek. Brain fart.
    No one on TD is gay. If suspect, it was probably because of the way they were reared.
    I apologize if any offence was caused. unless it was intended.
    You people, you think I know feck nothing; I tell you: I know feck all
    How much more grievous are the consequences of anger than the causes of it.

  4. #4
    Newbie
    Join Date
    Apr 2011
    Last Online
    23-02-2017 @ 06:48 PM
    Location
    Sattahip
    Posts
    17
    Quote Originally Posted by crepitas View Post
    555..this should be good...
    Why do you say that? Something wrong with the question?

  5. #5
    Thailand Expat
    crepitas's Avatar
    Join Date
    Apr 2013
    Last Online
    27-03-2017 @ 08:11 AM
    Posts
    1,965
    Sorry mate but I just have to ask:
    Why TF did you not buy an equivalent Hitachi pump..with unions same same? Maybe 20 minutes with a wrench and all set?

    I did the same about 12 months ago when our 10yo Hitachi started leaking..10 minutes back in business....

  6. #6
    Thailand Expat
    crepitas's Avatar
    Join Date
    Apr 2013
    Last Online
    27-03-2017 @ 08:11 AM
    Posts
    1,965
    Nuffink wrong with your question mate..just my humour.

    Obviously I don’t know what ailed the Hitachi pump but Thais are very adept of fixing stuff for a pittance if you can just find a good shop ?


    55 still waiting for our water cooler to be fixed under warranty...

  7. #7
    Newbie
    Join Date
    Apr 2011
    Last Online
    23-02-2017 @ 06:48 PM
    Location
    Sattahip
    Posts
    17
    First of all the Hitachi was only 3 years old. It seemed pretty foolish to replace it with exactly the same model. Secondly, while I have done a number of swapouts in the past, at age 75 now I prefer to pay someone else a few 100 baht to do it. So I would have used a contractor regardless.

  8. #8
    Sukhumvet
    VocalNeal's Avatar
    Join Date
    Jul 2007
    Last Online
    Today @ 10:10 AM
    Location
    Bangkok
    Posts
    9,781
    Quote Originally Posted by crepitas
    Maybe 20 minutes with a wrench and all set?
    You didn't include the two hours up to the axles in your driveway.

  9. #9
    Thailand Expat
    crepitas's Avatar
    Join Date
    Apr 2013
    Last Online
    27-03-2017 @ 08:11 AM
    Posts
    1,965
    Quote Originally Posted by expat2010 View Post
    First of all the Hitachi was only 3 years old. It seemed pretty foolish to replace it with exactly the same model. Secondly, while I have done a number of swapouts in the past, at age 75 now I prefer to pay someone else a few 100 baht to do it. So I would have used a contractor regardless.
    No offense mate....Fair enough...good luck from a 68yo..55.Wish I could find someone reliable to cut our grass and trim trees...shit being an old expat ain't it?

  10. #10
    Thailand Expat
    Slick's Avatar
    Join Date
    Oct 2008
    Last Online
    @
    Posts
    5,428
    You should post pics of the spring he left out and where it came from.

    Those pumps suck by the way. The hitachi constant pressure pumps are way better.

    You are going to have a hard time adjusting the pressure switch without pressure gauges installed on the pumps output pressure line.

  11. #11
    Sukhumvet
    VocalNeal's Avatar
    Join Date
    Jul 2007
    Last Online
    Today @ 10:10 AM
    Location
    Bangkok
    Posts
    9,781
    Quote Originally Posted by Slick
    You are going to have a hard time adjusting the pressure switch without pressure gauges installed on the pumps output pressure line.
    Technically the adjustment is easy. Measuring the actual pressure is different.

    Quote Originally Posted by Slick
    You should post pics of the spring he left out and where it came from.
    You take the plastic castellated cap off. It was under there.
    Last edited by VocalNeal; 26-12-2016 at 10:34 AM.

  12. #12
    Thailand Expat
    crepitas's Avatar
    Join Date
    Apr 2013
    Last Online
    27-03-2017 @ 08:11 AM
    Posts
    1,965
    Just for laughs as to Thai ingenuity:
    Many years ago bought a Chinese dirt bike…after a few months could not get the thing to operate (vendor had closed shop) Thought I was a smart cookie...Got it going a few times then gave up. It sat for a couple of years with 20km+ on the clock gathering dust. Got tired of looking at it and gave it away to our rubber tapper. Within days he was proudly riding it and still is..Frick!!TIT.

  13. #13
    Sukhumvet
    VocalNeal's Avatar
    Join Date
    Jul 2007
    Last Online
    Today @ 10:10 AM
    Location
    Bangkok
    Posts
    9,781
    ^ A mate brought me a Chinese 50cc scooter. Said it wouldn't run. He'd taken it to the local Indo mechanic, etc..

    The short version is that a mud wasp had built a nest in the tailpipe.

  14. #14
    Newbie
    Join Date
    Apr 2011
    Last Online
    23-02-2017 @ 06:48 PM
    Location
    Sattahip
    Posts
    17
    Quote Originally Posted by VocalNeal View Post
    Quote Originally Posted by Slick
    You are going to have a hard time adjusting the pressure switch without pressure gauges installed on the pumps output pressure line.
    Technically the adjustment is easy. Measuring the actual pressure is different.

    Quote Originally Posted by Slick
    You should post pics of the spring he left out and where it came from.
    You take the plastic castellated cap off. It was under there.
    It's clear where it came from. I put it back, but did not make any difference. It seemed to me that on the tiny schematic inside the pump that the spring is not to do with multi-story, but the level of the water supply. There's a diagram showing a lower water supply. Maybe to stop the water suctioning out?

    I'll play around with the adjustment when I have time.

  15. #15
    Newbie
    Join Date
    Apr 2011
    Last Online
    23-02-2017 @ 06:48 PM
    Location
    Sattahip
    Posts
    17
    Quote Originally Posted by crepitas View Post
    Quote Originally Posted by expat2010 View Post
    First of all the Hitachi was only 3 years old. It seemed pretty foolish to replace it with exactly the same model. Secondly, while I have done a number of swapouts in the past, at age 75 now I prefer to pay someone else a few 100 baht to do it. So I would have used a contractor regardless.
    No offense mate....Fair enough...good luck from a 68yo..55.Wish I could find someone reliable to cut our grass and trim trees...shit being an old expat ain't it?
    No worries. No, it's not shit at all. Just have to make some adjustments here and there. Fortunately with age and experience, I'm now able to figure out how to do that quite effortlessly.

  16. #16
    Thailand Expat
    Slick's Avatar
    Join Date
    Oct 2008
    Last Online
    @
    Posts
    5,428
    Anyway if you feel like fuckin with it, this is how you adjust the pressure switch. Make sure the power is off so you don't kill yourself. These pressure switches 'can' switch "L" or line power OR "N" neutral power. Fuk knows how somchai wired it. Assume it can be hot even if the pump isn't running.

    Locate it here:



    Pop off the plastic cover, there is a screw holding it down:



    You switch might look a little different with the cover off, this one is a replacement I bought, but they work the same even if yours looks slightly different. There should be a small screw with +/- indicated on it. Pretty obvious what that does. Turning it towards the + increases the "Cut Out" pressure and turning it towards the - lowers the "Cut Out" pressure.



    You really need a pressure gauge in the output side to the house to see what the fuk your doing when you turn the screw, but you can try it a very little bit at a time and see what happens.

    Take a knife or something sharp and scribe a mark into it so you can take it back to original setting after you try this and see that its not going to fix anything really. These pumps kinda suck but you can try.

  17. #17
    Sukhumvet
    VocalNeal's Avatar
    Join Date
    Jul 2007
    Last Online
    Today @ 10:10 AM
    Location
    Bangkok
    Posts
    9,781
    Quote Originally Posted by expat2010
    It seemed to me that on the tiny schematic inside the pump that the spring is not to do with multi-story, but the level of the water supply. There's a diagram showing a lower water supply. Maybe to stop the water suctioning out?
    Actually it is to maintain the prime and stops the water from draining back into a well and allows the pump maintain the pressure in the accumulator. In a multistory house the water in the upper floors would drain back to the pump. A broken spring will result in water hammer in the system.

    In a urban single storey house system connected to government water the anti-drain back function may not be necessary but doesn't do any harm.

  18. #18
    Thailand Expat
    Slick's Avatar
    Join Date
    Oct 2008
    Last Online
    @
    Posts
    5,428
    Quote Originally Posted by VocalNeal View Post
    Quote Originally Posted by expat2010
    It seemed to me that on the tiny schematic inside the pump that the spring is not to do with multi-story, but the level of the water supply. There's a diagram showing a lower water supply. Maybe to stop the water suctioning out?
    Actually it is to maintain the prime and stops the water from draining back into a well and allows the pump maintain the pressure in the accumulator. In a multistory house the water in the upper floors would drain back to the pump. A broken spring will result in water hammer in the system.

    In a urban single storey house system connected to government water the anti-drain back function may not be necessary but doesn't do any harm.
    This style of pump isn't for a well at all. That would be a jet pump your referring to. No prime issues with this style pump but the check valve spring should be left in there regardless. Dunno why somchai thought it was a good idea to remove it.

  19. #19
    Thailand Expat
    Slick's Avatar
    Join Date
    Oct 2008
    Last Online
    @
    Posts
    5,428
    Forgot to mention something about the pressure switch.

    They work on a "Cut In" and "Cut Out" system with a set difference of about 20 psi.

    So if you turn the screw towards the + and increase the "Cut Out" pressure, you are by default also increasing the "Cut In" pressure equal to the amount you raised the "Cut Out" pressure.

    A gauge costs nothing and I have no idea why nobody installs them.

    For example:

    If the pump, by default, "Cuts In" at 30 psi, and "Cuts Out" at 50 psi - when you turn the screw towards the + and increase the "Cut Out" to 55 psi, it will by default increase the "Cut In" pressure to 35 psi as well.

  20. #20
    Sukhumvet
    VocalNeal's Avatar
    Join Date
    Jul 2007
    Last Online
    Today @ 10:10 AM
    Location
    Bangkok
    Posts
    9,781
    Even your superior? Hitachi constant pressure pumps are described as shallow well pumps. Don't know where you got the idea that they are not.

    If they don't need an initial prime why is there a priming cap?

    The factory pressure switch setting for a Mitsubishi 150 W pump are on 1.4 Kg/cm and off at 1.9 kg/cm ( about 12 to 18m of head)

  21. #21
    Thailand Expat
    Slick's Avatar
    Join Date
    Oct 2008
    Last Online
    @
    Posts
    5,428
    Quote Originally Posted by VocalNeal View Post
    Even your superior? Hitachi constant pressure pumps are described as shallow well pumps. Don't know where you got the idea that they are not.

    If they don't need an initial prime why is there a priming cap?

    The pressure switch setting for a Mitsubishi 150 w pump are on 1.4 Kg/cm and off at 1.9 kg/cm
    Very shallow water supply maybe, but no kind of actual 'well'.

    If you are using it to pull water from a water source then yeah that changes things, maybe, but in OPs case the pressure from the volume of water in his storage tank permanently negates any need for prime or to ever think about it.

    Regardless there is no point to remove a check valve from a system like this.

  22. #22
    Sukhumvet
    VocalNeal's Avatar
    Join Date
    Jul 2007
    Last Online
    Today @ 10:10 AM
    Location
    Bangkok
    Posts
    9,781
    Quote Originally Posted by Slick
    Very shallow water supply maybe, but no kind of actual 'well'.

    If you are using it to pull water from a water source then yeah that changes things, maybe, but in OPs case the pressure from the volume of water in his storage tank permanently negates any need for prime or to ever think about it.
    Maximum suction head for the OP's pump is about 9 meters so yes a shallow well.

    Yes the OP's installation has a water tank and yes he lives in a single storey house so he doesn't really need a check-valve spring but there was one supplied and the "contractor" had no real need to remove it. Without the spring there is a slight delay, enough to induce water hammer in a different installation.

    One could argue that the force required to overcome the spring does detract from the pumps total output but not enough to worry about.
    Last edited by VocalNeal; 26-12-2016 at 12:03 PM.

  23. #23
    Thailand Expat
    Slick's Avatar
    Join Date
    Oct 2008
    Last Online
    @
    Posts
    5,428
    Quote Originally Posted by VocalNeal View Post
    Even your superior? Hitachi constant pressure pumps are described as shallow well pumps. Don't know where you got the idea that they are not.
    The hitachi is superior. The operate completely different than the Mitsu units with the baby pressure tank. The water runs through the switch and provides better flow and pressure. Honestly its night and day and probably why OP is unhappy with his Mitsubishi pump.

    Have you tried one? No trying to bicker with you but I don't know anyone who wasn't surprised by the difference. Not to mention there is zero pulsation in the water supply to the house.

    Quote Originally Posted by VocalNeal View Post
    The factory pressure switch setting for a Mitsubishi 150 W pump are on 1.4 Kg/cm and off at 1.9 kg/cm ( about 12 to 18m of head)
    Thats 20 psi "Cut In" and 27 psi "Cut Out"... 20 psi is nothing. Ideally it should be around 35 psi "Cut In" for a home but these pumps aren't made for this sort of thing really. The hitachi units are better at doing this job closer to this range.

    You can buy, at any local mom & pop hardware store in Thailand a direct replacement switch with preset settings in a higher range as well. I don't have any handy but off the top of my head they have a 1.8/2.4 unit for about 150 baht.

    Or you can try and adjust it your self.

    I have a feeling that if OP does adjust his pressures, the pressure switch is going to short-cycle and pulsate as the pressure tank isn't a big enough buffer at those pressures.

    Thats the reason my Mitsubishi pump is collecting dust. It sucked from the factory. It sucked when I adjusted the pressure and pulsated, it sucked when I bought drop in replacement switches of a higher calibration. If its pulsating, then the switch contacts are going to wear out real fast too.

    I been through 3-4 of these things and they just are not worth trying to 'make work' outside of the way they are packaged.

  24. #24
    Thailand Expat Thai3's Avatar
    Join Date
    Dec 2016
    Last Online
    @
    Posts
    1,301
    Always been disappointed with our 150 w Mittsu pump, no where near enough pressure upstairs, ground floor is fine but bathroom is pathetic. Never knew you could adjust them, will have a go. Sounds like the Hitachi is a better system but they don't last as long?

  25. #25
    Sukhumvet
    VocalNeal's Avatar
    Join Date
    Jul 2007
    Last Online
    Today @ 10:10 AM
    Location
    Bangkok
    Posts
    9,781
    Quote Originally Posted by Slick
    Thats 20 psi "Cut In" and 27 psi "Cut Out"... 20 psi is nothing.
    But he only has a 150W pump. I suspect the "other" switches you talk about are for ,say, a 300W pump.

    My 200W pump works fine for a three storey house with a shower on the top floor. It is in its own space and may cycle on and off but they are made to do that. Water doesn't pulsate and I can't hear it so.

    In Indonesia I had a small pump that I did adjust/measure using a pressure gauge but only because I borrowed one from the Instrument shop.

Page 1 of 2 12 LastLast

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •