Blue Flames on Fireplace.

[joemach]

I changed an old Heatilator 300 series fireplace from propane to natural gas.

All went well except that the flames are very blue. Not with the white tips that I noticed when it was running with propane.

Is this some sort of air/gas mixture out of wack?

The instructions say that the flames will be blue after startup for the first 20 minutes and then get the white tips.

I did start to see the white tips after about half an hour but not all of them like with the propane.

From a short distand away you really can't even see the flame when it is blue.

[kdean1]

I assume you changed the orifices and the regulator spring in the gas valve and then adjusted the gas pressure. That's to start. A combustion analysis is the best way to make final adjustments.
Color of the flame is not a reliable diagnostic process.

[Gary Warren Jr]

Sounds to me you have a better combustion now than you did.

[hearthman]

First of all, you should have the information in the conversion kit from HL. It would include either a burner change or adjusting the air shutter. Typically air shutters on gas fireplaces are wide open for LP and closed down to about 1/8" for NG but it does vary. See the mfr. Gas fireplaces burn with blue flame bases with yellow tips. The flames will start off bluish then the tips will yellow as the venting warms up and the flames stretch up a bit. This is normal. LP is a heavier fuel and is harder to get proper mixing on with an atmospheric injection burner so they tend to have more yellow flames. Hollywood always uses LP gas for the fireplaces so you can see the flames. They also are more prone to sooting and CO production.