Rayburn bm30o oil valve help. of7

[adypeach]

We have fitted a bm30 oil control valve to replace ci valve. The bm valve has a high fire screw adjustment but no low fire screw adjustment. The supplier says this is how they are now, preset. Is this correct? As it doesn't regulate on simmer its always on bake never any lower. Please help. I'm beginning to wish that I had fitted a toby.

 

[mysteryman]

That seems hard to believe, though it is years since I worked on one.

Surely there must still be low fire adjustments?

 

[adypeach]

There is a recess for where the screw should be. At the moment its idling at 170 c. Unsure what to do.

 

[outinthestix]

I've not seen any valve which could not be adjusted. Can you post pictures of the valve with the top plate removed ? Stix.

 

[adypeach]

There are 2 screws top and bottom of a white plastic slider. Hopefully these are the high and low fire adjustments.

 

[oilhead]

Remove the cutout in the topplate adjacent to the knob. Turn the knob to low, and the screw that appears in the aperture is the low fire adjuster. Turn ti the high position and the screw in the aperture is the high fire screw.
What flow rates are noted on the top plate? you ashould be looking for 4-13cc

 

[adypeach]

Many thanks. Its 4-13cc. Is it best to adjust low fire by tweaking a quarter of a turnat a time as at the moment its between simmer and bake approx 150 C.

 

[oilhead]

4-13 is the correct one, if it is new, then it should not need adjusting. If you go below 4cc on an 8" burner, it will not light the outer ring on continued low fire, and will carbon up, making higher fire impossible. Have you sampled the temperature with a thermometer as the gauges are notoriously insensitive. When one considers an Aga is designed to tick over at 200c, your 150 is more than passable.

 

[oilhead]

Meant to add, Don Engineering, who made the conversion kits for Rayburns and Agas always maintained that the only problem with O.C.V.s was the fingers holding the screwdriver.

 

[adypeach]

Ok. But it always used to run at a lower temp on number 1.

 

[oilhead]

Are you sure you have it set at the same depth as the old one? 1 or 2 mm can make all the difference