Mitsubishi water pump, again

[proton]

Bought new Mitsubishi water pump again WP115R, same as the last one, just had it put in. Last pump came on every time a tap was on, now out of 5 taps the pump only comes on with one kitchen tap open, does not come on for the washing machine or tap in bathroom upstairs, but does when the toilets are flushed. Its all coming off the one pipe from the pump. Cant understand why it just come on for one tap. Either needs adjusting or could it be faulty out of the box? 

[bbko]

Maybe air in the system?  Try "bleeding" it.

[proton]

1 minute ago, bbko said:

Maybe air in the system?  Try "bleeding" it.

 

Yeah that worth a try, another 'expert' put it in of course. Home pro would not do it as we have no tank, for some reason Mrs has always been against one, and it's illegal of course to pump off the mains

[NoDisplayName]

35 minutes ago, proton said:

 

Yeah that worth a try, another 'expert' put it in of course. Home pro would not do it as we have no tank, for some reason Mrs has always been against one, and it's illegal of course to pump off the mains

 

Wait, what?

 

You don't have a water tank, and are pumping from the mains?

 

I think it's possible to cause negative pressure in the community system, then pull contaminants in, you know, raw sewage or pesticides.

 

Can you check the air pressure in the reservoir tank on the bottom of your pump?

 

 

[proton]

6 minutes ago, NoDisplayName said:

 

Wait, what?

 

You don't have a water tank, and are pumping from the mains?

 

I think it's possible to cause negative pressure in the community system, then pull contaminants in, you know, raw sewage or pesticides.

 

Can you check the air pressure in the reservoir tank on the bottom of your pump?

 

 

 

Been like this for 12 years, how to check the air pressure in the tank? She thinks tanks are dirty!

[Pouatchee]

not sure if same model as me, but look on top of your tank. should have 2 black caps. unscrew the one in the 'middle-ish'. you should hear air coming out and water too unscrew slowwwwwly. let the air come out completely, then check to see how much water you have to add.  careful when taking off cap... watch for spring.

 

if one of your taps drains the small tank under the pump faster then you will get air in it. if the gvt water is slow at filling it you will get air in it. depending on times of day the water does not flow at the same rate... mornings especially. at my house at least

[NoDisplayName]

12 minutes ago, proton said:

 

Been like this for 12 years, how to check the air pressure in the tank? She thinks tanks are dirty!

 

Tanks are dirty?  Sure, if you leave them uncovered or never clean them.  All water systems leak.  Mains pressure keeps the yucky stuff out.  If you pull the pressure down, the yucky stuff will get sucked in through the cracks.  Pesticides, sewage, motor oil.....

 

I've got an automatic model with an attached 2-liter pressure tank, which has a schraeder valve to adjust pressure.   This may be of use, has some comments about other pump types.

 

 

[UWEB]

1 hour ago, proton said:

 

Yeah that worth a try, another 'expert' put it in of course. Home pro would not do it as we have no tank, for some reason Mrs has always been against one, and it's illegal of course to pump off the mains

And you do all your Mrs. want even if it is nonsense? Better to order a Tank tomorrow.

[NanLaew]

10 hours ago, proton said:

Bought new Mitsubishi water pump again WP115R, same as the last one, just had it put in. Last pump came on every time a tap was on, now out of 5 taps the pump only comes on with one kitchen tap open, does not come on for the washing machine or tap in bathroom upstairs, but does when the toilets are flushed. Its all coming off the one pipe from the pump. Cant understand why it just come on for one tap. Either needs adjusting or could it be faulty out of the box? 

 

What was the problem with the last one?

[proton]

3 hours ago, NanLaew said:

 

What was the problem with the last one?

pressure switch faulty and leaking tank

[natway09]

Try bleeding the air tank.

You can  pump from the mains but ensure you have a clack or non return valve installed

[proton]

3 hours ago, natway09 said:

Try bleeding the air tank.

You can  pump from the mains but ensure you have a clack or non return valve installed

 

Builder seems to have sorted it all. out, I got him to put a valve in as well. Home Pro want 1900 baht to install one which is way over the top IMO when all the pipes are there and it's just take out old put in new.

[peter267]

I may not have read all the threads - but are you very sure there is no leak on the pipework going to your errant tap - somewhere where you can't see it?   Hmm glue a valve in pipe work leading to that tap.   If closed, the pump stops - open the valve if the pump starts up a bit , it's leaking where you can't see?

[xtrnuno41]

Does the pump actually kick in or you notice water isnt coming out of tap?

If pump isnt kicking in, then it would be the pressure switch. You open tap, pressure drops and pump should kick in.

IF pump is kicking in, but no water, then air in system could be the trouble. Too less water in feed of pump.

 

Toilet is just a tiny valve, so seems thats is working, low flow. Tap open is already too big and pump doesnt deliver.

BUT the pump should run, as of creating low pressure for the switch, which activates the pump.

The intake is too low. You can try by just putting tap just very slightly open, like a toilet is working and see if water is coming then.

Dont know why a (extra?) valve is a solution, ok you limit the waterflow to your house. But then pump only would give water like the toilet is using to fill up. Very low. You will be annoyed again.

 

Possibility is, there could be a blocking in your water supply from where the feed is. IS there a valve in it and not all open?

You changed the pump , so water was set off to install pump. Somewhere there is already a valve, though?!

Maybe that main valve got broken and it looks wide open, but isnt. Maybe the builder is referring to that?

Or did they after all put it open?

Anyway you could check if main valve is all open. Maybe switch it open/close few times  to see if it is working.

However if you see main valve just slightly open there you have the problem.

If you have opportunity to disconnect the feed to the pump somehow, you can also see if a good flow is going in.

Of course you have to shut down main valve first before disconnecting. Then open it again and see if waterflow is very good.

IF not, then or valve , or other blocking, or low pressure, flow from water system.

Just some thoughts.

 

[Grusa]

18 minutes ago, xtrnuno41 said:

Does the pump actually kick in or you notice water isnt coming out of tap?

If pump isnt kicking in, then it would be the pressure switch. You open tap, pressure drops and pump should kick in.

IF pump is kicking in, but no water, then air in system could be the trouble. Too less water in feed of pump.

 

Toilet is just a tiny valve, so seems thats is working, low flow. Tap open is already too big and pump doesnt deliver.

BUT the pump should run, as of creating low pressure for the switch, which activates the pump.

The intake is too low. You can try by just putting tap just very slightly open, like a toilet is working and see if water is coming then.

Dont know why a (extra?) valve is a solution, ok you limit the waterflow to your house. But then pump only would give water like the toilet is using to fill up. Very low. You will be annoyed again.

 

Possibility is, there could be a blocking in your water supply from where the feed is. IS there a valve in it and not all open?

You changed the pump , so water was set off to install pump. Somewhere there is already a valve, though?!

Maybe that main valve got broken and it looks wide open, but isnt. Maybe the builder is referring to that?

Or did they after all put it open?

Anyway you could check if main valve is all open. Maybe switch it open/close few times  to see if it is working.

However if you see main valve just slightly open there you have the problem.

If you have opportunity to disconnect the feed to the pump somehow, you can also see if a good flow is going in.

Of course you have to shut down main valve first before disconnecting. Then open it again and see if waterflow is very good.

IF not, then or valve , or other blocking, or low pressure, flow from water system.

Just some thoughts.

 

How refreshing to see a brain actually working properly! Are you a Vulcan?

 

I can not fault your analysis, except you have not considered the effect of contaminants at various stages:- rust scale, sediments, etc. - and corrosion of parts, especially non-return valves.

[xtrnuno41]

7 minutes ago, Grusa said:

How refreshing to see a brain actually working properly! Are you a Vulcan?

 

I can not fault your analysis, except you have not considered the effect of contaminants at various stages:- rust scale, sediments, etc. - and corrosion of parts, especially non-return valves.

Rust, corrosion is not that an issue, as Thailand uses plastic pipes.

In the house there will be metal faucets, where corrosion could occur.

I have no clue how sour (pH) the water is from city water.

I assumed there will be no explicit non return valve, it is Thailand. As said in Thailand, you cant put a pump on watersystem, but it is a fact.

Sediments is blocking, however if flow is real low from sediments, than you have no proper working city water.

But maybe some one throw in a rock and is now blocking somewhere.

IF you use a well, then you can have more problems with sediments. Also pH, as I know water is pH 4 at my wife's house.

Well water needs to be laboratory tested first, to use. Otherwise you can have a fine and they shut you down. You need approval.

So logically I would first think then main valve. It is only logical, live long and prosper !

 

 

Just thought of new logical situation, the new pump had protection material on its connections and they "forgot" to take it off or out. Maybe stabbed a hole in it and left it.

[proton]

1 hour ago, peter267 said:

I may not have read all the threads - but are you very sure there is no leak on the pipework going to your errant tap - somewhere where you can't see it?   Hmm glue a valve in pipe work leading to that tap.   If closed, the pump stops - open the valve if the pump starts up a bit , it's leaking where you can't see?

No leaks, builder did find debris in one pipe and adjusted another tap but it's still not switching on for all outlets. Will bleed it then adjust the pressure switch. Never understand why they dont build them with stainless steal tanks, they always rust and leak after a few years, 10 for the last one.

[proton]

1 hour ago, xtrnuno41 said:

Does the pump actually kick in or you notice water isnt coming out of tap?

If pump isnt kicking in, then it would be the pressure switch. You open tap, pressure drops and pump should kick in.

IF pump is kicking in, but no water, then air in system could be the trouble. Too less water in feed of pump.

 

Toilet is just a tiny valve, so seems thats is working, low flow. Tap open is already too big and pump doesnt deliver.

BUT the pump should run, as of creating low pressure for the switch, which activates the pump.

The intake is too low. You can try by just putting tap just very slightly open, like a toilet is working and see if water is coming then.

Dont know why a (extra?) valve is a solution, ok you limit the waterflow to your house. But then pump only would give water like the toilet is using to fill up. Very low. You will be annoyed again.

 

Possibility is, there could be a blocking in your water supply from where the feed is. IS there a valve in it and not all open?

You changed the pump , so water was set off to install pump. Somewhere there is already a valve, though?!

Maybe that main valve got broken and it looks wide open, but isnt. Maybe the builder is referring to that?

Or did they after all put it open?

Anyway you could check if main valve is all open. Maybe switch it open/close few times  to see if it is working.

However if you see main valve just slightly open there you have the problem.

If you have opportunity to disconnect the feed to the pump somehow, you can also see if a good flow is going in.

Of course you have to shut down main valve first before disconnecting. Then open it again and see if waterflow is very good.

IF not, then or valve , or other blocking, or low pressure, flow from water system.

Just some thoughts.

 

 

Thanks very useful

[orchidfan]

2 hours ago, proton said:

No leaks, builder did find debris in one pipe and adjusted another tap but it's still not switching on for all outlets. Will bleed it then adjust the pressure switch. Never understand why they dont build them with stainless steal tanks, they always rust and leak after a few years, 10 for the last one.

Hitachi...which I have, DO manufacture a stainless steel model in their range. A few thousand baht more.

 

Also,all the houses in our moo baan (Pathum Thani) have underground, sealed (cap/lid can be rotated and removed if required).

After more than 10 years the water in the tank is crystal clear. Tank is automatically filled from the mains.

We don't drink this water, but everything else in the house and garden has great high pressure.

 

Of course if the tank (1000ltrs I think) gets inadvertently emptied, the pump gets hot and switches itself off automatically (built in safety device)

Pretty simple prime ~once its cooled down, then back in full operation.

[3STTW]

Apparently those Hitachi pumps are the biz, my buddy up the street has just had one installed and he's over the moon with it.

I bypassed my Grundfoss pump when I discovered that the city pressure was way better (and it doesn't surge). But with drought coming I've got a new tank and a Hitachi pump is on the list.