Firebird C26/Riello RDB problem

[James Price]

Hi,

Could I please have some advice with an issue with my parents Firebird oil boiler? They’ve been without hot water since NYD, their usual engineer can’t fix it and everyone else is busy for days.

The boiler is lifeless, the motor/burner will not run, no purge, not even a light on the control box.

**The boiler is not locked out.

The boiler has 240v to the control box, but no live from the control box to the motor.

I have tried a reset of the high limit stat.

The heat demand LEDs are on at the PCB (and flashing, which I’ve never seen before) but the heat demand wire to the control box is dead.

I have already changed the PCB and control box but it made no difference.

Any thoughts please?

Thanks,

 

[Terrywookfit]

Is this the model with a pressure switch ?

 

[oilhead]

If the lights are flashing, you could try new thermostat sensors. The flashing is a symptom of their failure.

 

[Terrywookfit]

If the lights are flashing, you could try new thermostat sensors. The flashing is a symptom of their failure.

Or measure their resistance , they are only NTC.
380k @ 0°
220k @10°
100k@ 25° As the boiler is cold this should give a good idea if fooked. Pretty sure all 3 are the same.
My first check would be pressure switch continuity.

 

[James Price]

Thanks both.

Not sure about the pressure switch, I’ll have to check the manual.

By thermostat sensor, do you mean the thermostat in the house? Is there not a flow sensor also, which would demand heat even if the thermostat sensor had failed?

 

[Terrywookfit]

No that is a room stat . There are 3 that plug into pcb to measure actual water temps .
The flow one is red, The tank is white and boiler is white with black band.

 

[oilhead]

Is this a combi or just heat only?
While the PCB lights are flashing, is the/are either if a combi/ pump(s) trying to run?
Have you checked for output from the room stat to the PCB? Have you got a feed out of the boiler control stat to the burner? IIRC, the control box will have 240 volt most of the time for post purge. Have you followed the fault finding chart in the manual?
When you say the usual engineer cannot fix it, do you mean he's looked it or cannot get there? When you changed the control box, have you got the right variant?

 

[snb]

deleted

 

[James Price]

Thanks for the responses.

Just to follow up on the issue, the problem was the pressure switch.

Thanks again.

James