Pump Inquiry

Coffee

Coffee

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Two years ago a Kikawa pressure pump was installed to provide an ['Amazon rainforest'] showerhead with a strong waterflow located in an inside-house groundfloor bathroom.

Recently I'd noticed a slow movement of the butt-hose (next to the toilet) every ten seconds... probably from either water or air.

There is no water dripping from the toilet or any bathroom tap.
That movement stops when I shut off power to the pump.

Eventhough the pump is effectively shut off if I open a bathroom tap (ie: sink or bath) a very small stream of water will run...approx 300ml/hour.

Personally I figured no water could pass through the pump without electric power.
Is my assumption incorrect?

If I manually shut the outside pump valve connected to the pump this stream of water to the inside bathroom effectively stops.

The 'pump man' from DoHome where I purchased said pump stated water from the water tank is flowing through the Kikawa pump due to gravity when the valves to and from the pump are open.
('Really'?? - I thought.)

In effect my inquiry is: 'how could water flow through the pump if there wasn't any power source operating the pump ?'

As I'm not a pump professional I'm seeking knowledgable replies. Thanking you in advance.

Pump specs
20231011_145510.jpg
The pump and tank setup.
20231011_145211.jpg20231011_145234.jpg

Any questions - please just ask.
 
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Coffee said:
Two years ago a Kikawa pressure pump was installed to provide an ['Amazon rainforest'] showerhead with a strong waterflow located in an inside-house groundfloor bathroom.

Recently I'd noticed a slow movement of the butt-hose (next to the toilet) every ten seconds... probably from either water or air.

There is no water dripping from the toilet or any bathroom tap.
That movement stops when I shut off power to the pump.

Eventhough the pump is effectively shut off if I open a bathroom tap (ie: sink or bath) a very small stream of water will run...approx 300ml/hour.

Personally I figured no water could pass through the pump without electric power.
Is my assumption incorrect?

If I manually shut the outside pump valve connected to the pump this stream of water to the inside bathroom effectively stops.

The 'pump man' from DoHome where I purchased said pump stated water from the water tank is flowing through the Kikawa pump due to gravity when the valves to and from the pump are open.
('Really'?? - I thought.)

In effect my inquiry is: 'how could water flow through the pump if there wasn't any power source operating the pump ?'

As I'm not a pump professional I'm seeking knowledgable replies. Thanking you in advance.

Pump specs
View attachment 69437
The pump and tank setup.
View attachment 69438View attachment 69439

Any questions - please just ask.
Click to expand...
To a layman, such as myself, your pump is bypassing allowing water to flow past the impellar-( that spinning do-hickey ) in the pump that makes the
water flow. Probably time for a new pump as, they are probably a sealed unit.
A question, I wonder why Somchai put the filling point so low ?.
 
FERRET said:
To a layman, such as myself, your pump is bypassing allowing water to flow past the impellar-( that spinning do-hickey ) in the pump that makes the
water flow. Probably time for a new pump as, they are probably a sealed unit.
A question, I wonder why Somchai put the filling point so low ?.
Click to expand...

7 year warranty hence the visit by the DoHome 'pump man' and his statement concerning 'gravity'.

If indeed correct I could build a pedestal.
 
Sounds to me like there's not enough water in the tank and Air is getting into the system.
It appears you are on city water to fill the tank that supplies the water to the pump to pressurize your system for the shower etc.

Most systems having in let pipe inside that runs the top with a shut off mechanical valve with a stem sticking out with a float that activates the valve when the sat water level as achieved. Example most toilets have the system. Not sure your tank is designed that way ?
I would not condemn your pump quickly, I will not going to the more technical problems possible.
A person would have to get up on top of the tank to look and see what's going on and make the necessary repairs.

I've done quite a bit of this work myself in the past but I'm too beat up to do any now for myself.

You need a good (hopefully) water system Thai mechanic person to check this out for you, would be my two cents or 1 baht
 
lightfoot said:
Sounds to me like there's not enough water in the tank and Air is getting into the system.
It appears you are on city water to fill the tank that supplies the water to the pump to pressurize your system for the shower etc.

Most systems having in let pipe inside that runs the top with a shut off mechanical valve with a stem sticking out with a float that activates the valve when the sat water level as achieved. Example most toilets have the system. Not sure your tank is designed that way ?
I would not condemn your pump quickly, I will not going to the more technical problems possible.
A person would have to get up on top of the tank to look and see what's going on and make the necessary repairs.

I've done quite a bit of this work myself in the past but I'm too beat up to do any now for myself.

You need a good (hopefully) water system Thai mechanic person to check this out for you, would be my two cents or 1 baht
Click to expand...

Outside Water Tank is full.

Affirmative, Lightfoot - same setup with ballast balloon at top.
 
@Coffee not being able to see under the cover of the pump can I assume this is a pressure pump. Pressure pumps have a air tank that has a bladder in it.
If this is the case. You have not checked the air pressure in this tank and it has dropped below specification (normally 5 to 10 psi) Its written on it. After turning your pump off pressure is stored in the tank and water will flow for a short time. With the pressure low in the tank switching will also become erratic and pulsations will be noted as in bum gun movements. There is a Schrader Valve at the top of the tank that you can check the pressure with a tyre gauge.
Water will only siphon through the pump if the head of water is above any outlet of course. The water will be just leaking past the butterfly valve. They only stop water going back the other way.
 
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Rice said:
@Coffee not being able to see under the cover of the pump can I assume this is a pressure pump. Pressure pumps have a air tank that has a bladder in it.
If this is the case. You have not checked the air pressure in this tank and it has dropped below specification (normally 5 to 10 psi) Its written on it. After turning your pump off pressure is stored in the tank and water will flow for a short time. With the pressure low in the tank switching will also become erratic and pulsations will be noted as in bum gun movements. There is a Schrader Valve at the top of the tank that you can check the pressure with a tyre gauge.
Water will only siphon through the pump if the head of water is above any outlet of course. The water will be just leaking past the butterfly valve. They only stop water going back the other way.
Click to expand...

From opening sentence of OP: "...a Kikawa pressure pump was installed..."
Your assumption is correct.

1697168549325-2078960407.jpg16971686235151464700752.jpg

Rice, I wonder why would this slow water flow into residence commenced following two years of installation ?
Any thoughts...or just Murphys Law ?

Interesting comment. Thank you.
Where would this Schrader valve be located ?
1697168962120-1376832606.jpg

Edit: Murphys
 
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@Rice Another 'pump man' is supposed to be here Saturday morning.

Can you decipher this ?
20231013_123010.jpg

Is this "pressure setting" for air intake ?

Thanking you in advance Rice. :)

I'm attaching a parts schematic below but I cannot locate a Schrader valve.
20231013_122741.jpg
 
Possibly you could bleed the system of air my opening the primer cap, the worst thing that would happen is a little water will leak out.
I don't see a reason why the pump impeller would be cavitating, but strange things happen.
If I was my system I would put a pressure gauge on the outlet waterline from the pump.

If it comes down to taking the pump in for service.

There's a shop in Surin plaza that sells parts for Tools pumps etc. I think it's across from a coffee shop .
Last time I had my Hitachi pressure pump seals and bearings replaced, I had them do it requesting they change inner and outer seals and bearings at same Time. Their repair guy did a good job and did what I asked him to, it's lasted a long time I'm still going.
Previously I had the job done by another shop that took the quick fix by replacing all in one seal and bearing.

Just my one baht again.

That's a pretty fancy Pump you have Coffee

​

 
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There is a lot of different style of pump I was guessing what was under the cover. I was looking for a small pressure vessel like this
1697181672126.png
Yours does not have that it is a simple impeller drive system with a pressure differential switch that turns it on when a pressure drop is detected. Now I know that I would say. There is crud in the pressure switch and non return valve. In other words it needs a clean out.
That message on top of the instruction reads if you have done the preliminary maintenance steps. (bet you have not) call the dealer or a qualified technician. :p
 
Rice said:
Now I know that I would say. There is crud in the pressure switch and non return valve. In other words it needs a clean out.
That message on top of the instruction reads if you have done the preliminary maintenance steps. (bet you have not) call the dealer or a qualified technician. :p
Click to expand...

[I wonder exactly what preliminary maintenance steps they would be referring to...bleeding the water tank annually ??]

@Rice Which part number is the 'non-return valve' in the schematic posted (above) in my post #9 ?

---- ---- ---- ----
@lightfoot Primer plug was full to brim. That was the first item I checked before ever contacting DoHome; also the first thing their 'pump man' checked.
That pump man did say he would return Saturday afternoon with two 'pressure valves' to install on the hot and cold shower fittings inside the residence to see if that would alleviate the issue.
---- ---- ----- ----

(Keep well in mind that this THB13,000 (2021 price) pump is still well under its 7-year warranty.)
 
Which part number is the 'non-return valve' in the schematic posted (above) in my post #9 ?

I should have had a closer look at the schematic. Nope no NRV that explains the siphoning of the tank. 555
I bet the problem is in the flow setting 22-0.
Sorry was not paying attention been looking at air tickets !
 
Now there are two 'pump men' scheduled for late this afternoon.

(I hope this is NOT when I am told that there is a potential failure in the PVC pipe somewhere underground between the pump and the inside fixtures. :-(
 
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