Chaff boiler clicks on and off

[ChippieBrian]

Hello,
I'm new to this forum as I stumbled across it when trying to identify a problem.
It seems lots have had the same problems so I was able to follow your advice and fix the boiler with not to much problems, so thank you all very much.
Now another problem seems to have cropped up.
I have a Chaff and Maury 80 boiler and had the problem with the flexi pipe to the pressure vessel blocked which I fixed, the PV needed air so I charged that and the seal to the heat exchanger from the plastic hydraulic unit was leaking so I fixed that.
The boiler ran perfectly for about a day and a half but now it keeps clicking on and off. The central heating was up to temp, the pressure correct and all seems fine but it clicks on for about 5 seconds then clicks off, then after 20 secs or so does it again and so on.
Any help would be greatly appreciated.
Brian.

 

[Dan Robinson]

When was it serviced last?

 

[ChippieBrian]

When was it serviced last?

Hi Dan,
It was serviced about 18 months ago when I had the last problem.

 

[Dan Robinson]

Is it hot when it clocks off?

 

[ChippieBrian]

Is it hot when it clocks off?

It was but now it's cold and still trying to click on but doesn't seem to be able to, or rather only for a few seconds.

 

[Dan Robinson]

hhm.. I can't decide whether it is a problem with the fan or perhaps the pump.

Is the fan spinning properly?

 

[ChippieBrian]

hhm.. I can't decide whether it is a problem with the fan or perhaps the pump.

Is the fan spinning properly?

Where is the fan? It sounds like the pump is running, it's got a constant hum.

 

[Dan Robinson]

The fan is at the top, but if you had to ask, I would advise you get a RGI in.

Its just one of those questions.....

 

[ChippieBrian]

The fan is at the top, but if you had to ask, I would advise you get a RGI in.

Its just one of those questions.....

Ok, so last night the boiler should have switched off by the timer but it didn't.
I could hear the pump running all night and the boiler clicking on and off.
The upstairs rads are slightly warm and the down stairs ones cold.

I will get an RGI when i'm satisfied i've done all I can myself, monies tight and all that.

 

[peter the plumber]

hi i f i can remember these boilers have two flow switches that get stuck they work on a plunger.would not hurt to drain the boiler and clean them.also check to see if continuty is ok with multi meter pete

 

[ChippieBrian]

hi i f i can remember these boilers have two flow switches that get stuck they work on a plunger.would not hurt to drain the boiler and clean them.also check to see if continuty is ok with multi meter pete

Yes!! Excellent Pete, the flow switches were corroded. I gave them a rub with wire wool and put them back and it seems to be fine now.
Very much appreciated.