potterton puma 80e problems

[shadwell]

hello,
I hope that someone can help me.

i've had this problem for some time now. when the ch or hw is turned on everything works for a couple of minutes, then the boiler starts to sound like a kettle and then the lockout light comes on.

i keep resetting but the problem persists.
thanks.

 

[Gasman1015]

Air in pump or pump not circulating.

 

[shadwell]

what do i do. will i have to change the pump?

 

[shadwell]

ive just checked the pump and the spindle rotates etc when pulled out and re-engages fine.
how do i get rid of the air in the system?

 

[kevplumb]

check the auto air vent is open [/img]

 

[shadwell]

the auto air vent is open. i changed this a couple of years back

++++++++++++++++++++++++++++++++++++++++++++

engineer has been in before xmas and has already chx'd the main board and the board with the reset button on.

problem still persists

 

[Agile]

Call him back again!

 

[ChrisR]

Hmmm. How long does HW stay on if you have good flow from taps?

 

[shadwell]

it stays on until you switch the taps off then the boiler will boil up and lockout.

 

[Baxmax]

Drop the front panel expose the cicuit board turn on a hot tap a red led should come on on the pcb turn water off the red led should go off almost immediatly if not the micro switch is sticking on the dhw differential valve, or the diff/diaphram need replacing...

 

[shadwell]

thanks for that ill try that now

 

[shadwell]

with the ch on i turned the hot tap on and the red led lit. i then turned it off and it went out immediately.
after the light went out the boiler began to boil like a kettle again and then it locked out.

 

[ACOperson]

Scaled / blocked heat exchanger? Is pump overrunning?

 

[shadwell]

ive bought some cleanser today along with some silenter. not put it in yet do you think this will work.

how do you know if the pump is over running?

 

[ACOperson]

If the h/e is very badly blocked then it may not help. Hard to diagnose without seeing the boiler.

You can see if the pump is overrunning if you turn the CH on at the programmer / on boiler. Let it reach normal working temperature (run for one - two mins), then remove the call for heat at programmer / boiler - BUT DO NOT SWITCH THE BOILER OFF AT POWER OR PUT ON STANDBY as this will stop the facility from working!

If the over-run facility is working, once the flames go out on the burner, the pump should remain turning for a short time to dissipate heat away from the heat exchanger. If it is not over-running then the boiler can overheat, however on a Puma this is unlikely to be the cause of such extreme problems as you are experiencing.

It really sounds like the pump is at fault to me somehow, are you 100% certain that it is OK? Try having the boiler switched off & cold, undo the spindle and pull forward, then try turning the spindle once engaged onto the impeller, see how easily it turns. It should move fairly easily, if it takes even a bit of effort, the pump is to blame for your problems.