Worcester Heatslave 18/25 not firing

[AndyH562]

Direct wired Honeywell thermostat working.
Calls for heat and hot water. Full oil tank. Tigerloop has oil.
Boiler just stoped working.
Does not lock out. I can hear the switch and then a gentle fan noise but no pump action therefore does not even try to fire up.
Resets do nothing.
Hard to know if a solenoid..elecrrical fault or perhaps pump has gone.
Can't get an engineer out this week.
Anyone else experiences a similar problem?
Don't mind getting my hands dirty..my old external boiler I've changed most parts but first-time come across something like this.
Thanks to anyone's input.

 

[Bosswhite]

Have you checked the Photo Cell, unplug and clean off the eye , it could be covered with soot.

 

[AndyH562]

Thanks for the tip. Unplugged but was spotless, cleaned anyway but no life.
I can hear power to diverter. vibrates but nothing else happening.

 

[oilhead]

99% photo cell if a Riello burner. Unplug photocell from control box, restart burner. If it lights and goes to lockout, replace photocell.

 

[AndyH562]

Thanks Oilhead. Will try this when I get home from work tonight and let you know.

 

[Bosswhite]

A couple of other simple problems, is oil getting through, during the summer you could have condensation in the Tank, water getting into pipe or if the tank has been filled recently disturbed muck in tank blocking Tank Filter.

 

[AndyH562]

Thanks Bosswhite. Will check the photocell first and if that fails will look at the oil.
Tigerloop is full of oil would that not indicate good oil flow. Previous boiler was gravity fed so not sure if indicates flow ok.
What would e the easiest way to check oil is flowing to the pump?
Tigerloop one pipe from tank and two to the boiler

 

[Terrywookfit]

Have you tried resetting the two limit stats under control panel.

 

[AndyH562]

RDB 2.2 Greendale burner. Not the usual Riello red casing though.
Photocell does not connect to the control box and can' see where it connects unless I remove the control box and burner. Not going to manage that with my 2 year old daughter running around.
No other reset button s under the control box. Separate reset box nextcto thermostat control.

 

[oilhead]

There is one screw that holds the lid of the control box closed. The photocell plugs in and should be accessible. You need to drop/pull out the control panel. Consult your Installation instructions to identify the two screws you need to remove to do this.

 

[AndyH562]

Thanks I will do that.
Before I do need a quick education on tigerloops. Gravity fed oil run out free flow. Tigerloop facing it two pipes. Pipe one and two connect to the oil pump. pipe two is first connected to a shut off lever. When I undo the connection to check the oil there is no flow. Can I assume I should have flow or only flows when system is closed?

 

[oilhead]

The Tiger Loop is an oil de-aerator that incorporates a series of non return valves. It essentially converts the burner pump into a fuel supply pump where the supply is lower than the appliance. The oil pump draws fuel from the Tiger Loop, feeds the nozzle and returns the excess to the loop. The oil used is replaced from the feed from the tank by the vacuum the pump produces. If you disconnect the pipes from the pump, the Tiger Loop will drain via the return pipe if the loop is higher than the burner. If there is a gravity head on the supply, then you can still get flow through the Loop.

 

[AndyH562]

Thank Oilhead now fully understood.
Update. Changed the damaged pipes from the tigerloop but when boiler turned on Tigerloop is not priming with oil.

Stripped down the boiler, removed burner to access screws to the control box, unplugged photocell and tried to restart boiler.
Still nothing, servo on diverter kicks in and moves the arm, then a humming noise but nothing else.

What canI try next? Likely culpit? I am guessing if the oil pump was working then the tigerloop would start to fill with oil.

One good thing with all this is I am learning my way around this boiler as I did in the one in my old house.

Much thanks to all for you advice so far.
Look forward to finding out what the porblem is.

 

[Terrywookfit]

Did you check the overheat stats as I suggested.

Underneath the control panel below the thermostat knobs.

 

[AndyH562]

There is the reset button below the water temperature dial on the control panel. Fist thing I tried. My reset buttons are not on the boiler housing but a seperate unit on the wall.
I tried these also but does not even go to lockout.
I imagine now that it must be the solenoid or oil pump.
Happy to be corrected on my assumption.
Thanks