Warmflow boiler burner problems

[steve1]

The burner on our warmflow boiler, ( reillo ), seems to have a mind of it's own, when the room stat is asking for heat the burner will fire for about half an hour then stop, although i can still hear the fan and central heating pump going, then about half an hour later it will fire up again, and it will just keep on doing this all the time.
Have changed the control box on the burner, but still the same, what should I look at next.
Thanx.

 

[dontknowitall]

Sounds as if it's being starved of oil. If the tank is low I'd suspect this before trying to do anything else. If over half full then I'd suspect the pump (or oil leak?)

 

[tamz]

When the boiler thermostat reaches its set temperature the burner cuts out until it cools then comes back on again but half an hour to cut back on is too long. Check the photocell.

 

[Bartdude]

Are the radiators and water hot enough? You need to check whether the burner is receiving the signal to fire or not. Is the burner locking out?

 

[tamz]

It will be sticking in pre purge. Photocell.

 

[dontknowitall]

2 or 3 things here ... shall we have a sweepstake?

if I'm wrong ...

 

[steve1]

I am picking up a Photo-cell 2morrow, so at least I can eliminate that, as for the oil, the tank is full.
When the burner is not firing I have removed the coil from the solenoid for the oil and checked to see if it's geting a signal to open the valve up, it's not, boiler not locking out either.
Keep your thoughts coming.

 

[tamz]

Photocell.

It need to sense it is dark before it will allow it to spark then pick up the light to keep it burning.
The cell is breaking down and not sensing the dark so keeps the motor running waiting for a signal to spark. It won't lock out just keep running until the resistance is high enough to send a signal. Temperature changes the resistance in the cell slightly so it will eventually (hopefully) light as it cools.

 

[steve1]

Whilst I'm waiting for the P/C to arrive, I thought I'd have another look at the burner, and have noticed that just before it actually fires up again there is a clicking from the burner area, probably a relay or something in the control box, it does this about half a dozen times before it actualy fires up.
Does this make any sense to anyone.

 

[tamz]

Check to see if it is the photocell by disconnecting it then switch the boiler on. If it fires then goes to lock out it is definately the pc.

 

[steve1]

P/C was the problem after all, boiler behaving itself now, thanx for all your suggestions.
Now it's all up and running i was wondering what is the most efficient way of running the heating system, ie. how often should the boiler/burner be running, should the boiler thermostat be set in a particular way that the burner just cuts in now and again to bring it back up to temp. hope this makes sense.

 

[tommydog]

When my boiler starts from cold, it runs continuously for about 30mins to get up to temperature, shuts down for about 5mins and then flares again for around 10 mins, and so on. when its very cold it will run with a higher frequency as the water in the radiators cools down faster

The timing will depend a lot on how many radiators you have, the room temperature (i.e. how fast the radiators radiate and cool down) and the setting of the boiler thermostat, which should determine how hot your rads get. your boiler thermostat switches your riello burner on and off to maintain the desired heat of the radiator water. i get my riello warmflow boiler spare parts from sparesgiant.com

 

[kimbo]

Just a thought,is the overheat stat a self resetting one or a manual one, the worcesters used to do this when they overheated and the self resetting oh stat would reset it self and away it would go again.