Water heater flame help - adjustments not having any effect

I only had a single burner going when I measured that. I'm not sure how to adjust my pressure regulator - if it's adjustable or not.

The last time I was testing things, my combustion chamber was still damp from me cleaning it out more thoroughly with water. Now that it's dried, the flame seems much less orange. It's not perfect, but it's mostly blue now. And I don't see soot collecting anywhere. So I'm thinking now that maybe it's ok.

I'm going to just keep an eye on it and see how things work out on my next trip.
Thanks for the help and ideas.

How many propane appliances did you have in service when you measured that 12" WC?

Should have at least 50%....better if 100% and adjust your propane regulator to hold 11" WC

Did you adjust the gas valve to restrict the gas a bit?
Not familiar with these but have adjusted stoves and furnace gas valves.
Set screw is often under another screw plate cover of sorts.

Thanks RV papa, I checked and it looks OK in that regard. I don't know how to tell if that was the orifice that it came with the factory, but it does appear to be the right size as marked.

I just verified pressure at the orifice too (looked like my stove had it's own regulator). But still showing 12".

Hmm.... what a bummer. Running out of ideas.

The picture you have of the orfice looks to be #55 or 56. Easy to check if it was over sized. Find a 1/16 drill bit and try for size as a measure. It should NOT fit. If the orfice is the proper size it is about 5 to 10 thou less than 1/16.
Art.

So I checked the LP pressure at the stove (from a burner on high) and it's 12". Maybe a little high, but not high enough to cause problems I'd expect.

So if the LP pressure isn't too high, and everything is clean - then how can I be running rich? Could the orifice be too big - maybe the previous owner dorked around with it? What harm could come from me trying a smaller orifice?

A few pics, if it helps:

Valve Jet


Combustion chamber


Overview

Bummer - no luck cleaning the orifice. Seems like no change (looked clean when I took it out - but cleaned it anyway).

I double checked the burner tube - wire brush, etc. Even wire brushed, CLR'd, and hosed out the big combustion tubes all through the U-turn. Everything's rusty still, but nothing loose or flaky.

I did notice that the burner tube was not perfectly aligned with the jet/valve. So I bent the valve mount to make sure the jet was better aligned with the burner tube. That may have helped some - but not dramatically.

So still looking at a big floppy flame with too much orange most of the time. Sometimes it's actually pretty clean and blue, but more often there's a lot of orange. The shutter adjuster now has some effect, but not enough, and not too consistent (more effect on sound than the flame appearance).

I tried nearly closing off the tank, as well as running a couple stove burners at the same time - to see if it affected pressure or anything. No real effect. I also tested the fridge today and it seems happy on LP - clean blue flame.

Even in this state, the 6 gallon heater goes from cold to max in about 10 minutes. That's fine for me if it's safe and not going to empty my tanks in one shower's worth. It does give a bit of a belch at auto-restart though which is disconcerting.

Also tried feeding from both different LP tanks.

So I'm thinking I need to verify some pressures. I don't see any adjustments that people mention. Is the brass set screw in the center of the gas valve a pressure adjuster? I don't see an adjustment mechanism at the tanks.

Thanks for the ideas... kind of frustrating, as it doesn't seem to be that complicated of an instrument.

That air/mixture window needs to be fully open and any restrictions removed for more air to move toward a blue flame.
I would also consider adjusting the propane valve to reduce the flame to see if it helps. Note the position of the adjusting screw to put it back same if no help.
Soot in the combustion chamber can also affect how it burns. Give it a light scraping or brushing then sweep it out.

Also try cleaning The exhaust side or where the hot air comes out at the top a golf ball should be able to roll through the tube(exhaust) from top to bottom.