RDB boiler not starting (video)

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My oil heating is set on timer to come on every morning. I noticed 3 or 4 of mornings ago it didnt come on. I was able to press a reset button that was behind a cover that i screwed off on a small grey box (see picture) and the burner fired.

Fast forward to yesterday morning and the burner seemed to come on for an hour before cutting out (which I didnt realise as I was sleeping, I since figured the hot water wasnt that hot, so the burner wasnt firing for long). Then, last night the burner didnt fire again. I pressed the red reset button on the burner and off it went, but again cut out after, lets say an hour.

So I thought I would take a look this morning & here I am. This morning, the burner wont fire. It sound to me as though it is struggling to get power, like its runnning on half the power of mains electric is normally has if that makes sense. I made a quick video to see if any of you guys can help... Would be appreciated.

(edit, i also think the red light on the reset button isnt as bright as what I thought it was)...


 

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update:

unplugged & plugged in the boiler from the mains (leads in boiler housing), this seems to have given power again, loosened bleed vavle - oil is there and is pumping when boiler tries to start but it doesnt fire.

I just checked the oil I am a bit low in the sense the oil lovel has dropped slightly below the top of the outlet but oil is still flowing to the boiler when i open the bleed screw.


 
Motor capacitor or seized oil pump. Or both |
As you say your oil is low it may have sucked water in.
 
Thank you Terry

I am going to try a new capacitor & a few hundred litres of oil. The capacitor looks pretty simple to change, but these can be dangerous right? Does it need discharged? I'll disconnect the boiler from the mains & pull off the capacitor at the spade connectors?

Lastly, can I buy this type of capacitor at a local electrical wholesaler or would it be plumbing supplies etc?

thanks for the help, i appreciate it.

capacitor1.JPG capacitor2.JPG
 
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A heating merchant will have the correct part, but any capacitor with the same values will suffice, but you may have to adapt the mounting and connectors.
 
A heating merchant will have the correct part, but any capacitor with the same values will suffice, but you may have to adapt the mounting and connectors.

Thank :) is it safe to just pull of off now at the connectors? I’ll take it with me to a local shop.
 
Thank :) is it safe to just pull of off now at the connectors? I’ll take it with me to a local shop.

It isn't a standard electronic capacitor, it is a special mains voltage rated type, intended as a starter capacitor.
 
Just short the terminals before touching them. For peace of mind. TURNED OFF !!!
 
ok, thanks guys, tried to short the capacitor but no reaction. will try to source another one locally and report back. thanks again for the help.
 
ok, thanks guys, tried to short the capacitor but no reaction. will try to source another one locally and report back. thanks again for the help.

oil pump about 80 quid with new drive.Best getting a boiler man to set it up and clean the oil filters including dipping for water content. £150 - £200 approximately.
 
oil pump about 80 quid with new drive.Best getting a boiler man to set it up and clean the oil filters including dipping for water content. £150 - £200 approximately.

no point trying a capacitor then?
 
Take oil pump off and turn shaft by hand.
If it is tight its prob fooked.
With pump off turn burner on and see if motor runs..
 

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