Mitsubishi water pump?

[proton]

New about 12 months ago, no problems until a few of weeks back. Now it will come on for a couple of seconds every 1-2 minutes. Turned everything off including the inlets on the toilets, still the same. Is this is this likely to be a small leak some where, or the pump? All the pipes are in concrete of course so no chance of finding a small leak.

 

This sort of pump

 

 

[Bill97]

Leak possible 

 

pressure valve defective possible

 

air in pump system possible 

 

 

triple check turned everything off and toilet running 

 

[novacova]

Possibly the solenoid, try tapping it and see if it responds. An easy fix.

[Crossy]

2 hours ago, Bill97 said:

Leak possible 

 

pressure valve defective possible

 

air in pump system possible 

 

triple check turned everything off and toilet running 

 

 

This ^^^.

 

Can you hear "gurgling" at the pump when it's not running (non-return valve leaking)?

 

Is there an isolating valve on the pump outlet you can turn off?

[proton]

53 minutes ago, Crossy said:

 

This ^^^.

 

Can you hear "gurgling" at the pump when it's not running (non-return valve leaking)?

 

Is there an isolating valve on the pump outlet you can turn off?

 

I think it might be the air in it, I remember bleeding the old one once or twice over the years and that sorted it out, will try tomorrow

[Clapped out]

19 minutes ago, proton said:

 

I think it might be the air in it, I remember bleeding the old one once or twice over the years and that sorted it out, will try tomorrow

Yup, I'd go with that as the first port of call

Years ago we relied on a pump like that and every couple of months we had to bleed it

 

[MangoKorat]

I have a Mitsubishi pump and mine was coming on intermittently without it seemed - any reason.  The pump senses a drop in pressure caused by the opening of a tap or other demand for water.  My problem was calcium build up in a toilet cistern that was not allowing the float valve to fully close when the cistern was full.  It was only causing a tiny demand - very hard to see. You could have a similar problem.

 

Assuming you use a storage tank, the way to check it is as Crossy says above - shut the outlet valve. If it continues to come on, the problem is almost certainly with the pump, if it stops coming on, you have a problem with your plumbing. However, if you are using 'City Water' without a tank and simply using the pump to boost pressure, the problem could be air in the incoming supply.

 

The above assumes your pump has been correctly fitted with an inlet and outlet valve.

 

I've used Mitsubishi pumps for many years and found them to be very reliable. They are however, as with so much of your plumbing, susceptible to the Thai water demon 'Calcium' - as all other pumps are. I've heard of calcium causing the pressure valve to fail but never experienced it.

 

Never had to bleed mine by the way - if you have to bleed a pump regularly there's a very good chance there's a leak on the inlet side or your tank regularly runs out.