bolgett convection oven

[smurphy]

converted oven over from lp gas to natural gas.Replaced gas valves, drill out pilot and burner orfices to proper btu rating.Gas pressure is at 3.5 Wc, burners are clean.My problem is when the burners ignite a low pitch whistle comes from the burner orfices.Double, tripled checked the orfice sizes and talked to tech support for proper size.Has any one ever ran into this problem with any gas equipment?

[Wild Leg]

I used to work on these things, long ago. Nobody within 100 miles would touch 'em, so I took the first one on for a good restaurant customer.
Made lots of money on cooking equipment.

Are you sure the noise isn't coming from a flex-line connector? They will whistle when too much gas flows. Change it to hard piping, or to a larger size.

Is 3.5" the right pressure? It used to be pretty much the standard, but be sure the factory recommends it for this application.

Is the gas valve rated large enough for the btu's required?
Double check it.

Good luck!

[smurphy]

3.5 wc is the right gas pressure, and i have 3.5 inches at the gas manifold.

[mike3]

Check the size of the flex connector if it has one. To small a connector will produce a whistle type sound. If that isn't the problem you may have a burr on one of the orifices.

[mike3]

OOPS bwal2 beat me to it. Guess I should have read his post better.

[smurphy]

Gas connector is a 1" quick connect gas line, No burrs in orfice body and also ran orfice drill both ways though orfice.