Everything Works but the Stove! Propane puzzler...

[JRD]

Interesting propane problem on my White Hawk 24RKS: all propane appliances work as usual except the Atwood stove.

All propane lines to the stove appear to be intact and burners are clear. The system has operated as it should for the past two years until yesterday.

Furnace, fridge, and water heater have good propane supply and operate normally but the stove has no gas supply without the workaround described below.

Strangely, I can get propane to the stove if I first set the fridge to “gas” mode and then turn on the stove. Propane will then flow to the stove and it will light and work normally until shut off. If I return the fridge setting to “auto” (electric) mode, propane ceases to flow to the stove after it’s been shut off and it will not re-light until I return the fridge to “gas” mode.

This one’s got me scratching my head. What do you think could be causing this and how can I fix it?

[WinnieView]

How much in the tank(s)?

[JRD]

Quite full and they are heavy. All propane appliances except the stove are working normally and the stove works intermittently as described above so the gas supply is there.

[WinnieView]

It sounds like a pressure issue to us caused by near-empty tank(s) or regulator issues.
Sorry we couldn't be of more help. Someone else should be along soon.

[RedHorse1]

Do you have an oven and does it work?
I’m guessing the stove and fridge are on the same section of gas line but it’s just a guess.
I’d look at the regulator and then examine the lines for crimps or damage. This is an odd puzzle, keep us up on what you try and what you find.

[JRD]

Haven’t tried the oven lately but it seems like I’m priming the stove’s gas line by allowing propane to flow to the nearby fridge in “gas” mode. Crazy I know.

When I switch the fridge back to electric, turn off the stove, and then try to re-light the burners there’s no gas flow to them. Even after they’ve been lit for 5 minutes or more while the fridge was in “gas” mode.

I’m wondering about the small regulator in the range top itself but never heard of one failing. What do you think?

[JRD]

.... the main regulator by the tanks seems to be working properly as the fridge, water heater, and furnace are operating normally.

[curver900]

So the fridge allows gas to the stove when the fridge is on "gas" when on auto or electric the stove doesn't work.

Does the stove work when the fridge is set to off?

I would look and see how the fridge is plumbed... my bet would be the regulator to the fridge causing some sort of issue for gas flow to the stove.

Seems odd... that the stove would work when the fridge is on gas if it was a low gas problem... I would expect the exact opposite the stove would NOT work when the fridge is on gas...

[JRD]

Just tried and no, the stove burner won’t light (no propane flow) with the fridge switched off either.

The only way propane flows to the stove burners is if another gas appliance is operating. Very strange indeed.

Seems to be something in the stove itself. I suspect the stove’s regulator but don’t understand why it would work while other gas appliances are running but not on its own.

Thanks for all the replies. Hopefully we can figure this out. We are traveling so I may not be able to get back to the forum until tonight PST, depending on WiFi and cell availability.

[DaveT]

How cold is it?

[curver900]

quite the mystery.. logic says there is a valve that opens when you turn on the fridge and closes when you shut it off... but that makes no sense at all.. I would think there is a T behind the fridge.. one line goes to the fridge regulator while the other other part of the T goes to the stove to its regulator... puzzled.. to say the least...

[us71na]

If you recently changed out an empty tank or just opened you tank valves for the season, you may have tripped the gas line flow limiter. You need to allow it to reset. Try this. Turn every thing off. Go to the tanks and close the valves. Carefully crack open the hose connector to the tanks until you hear a slight hiss or smell a bit of gas. Then tighten all tank connections. Tap lightly on the regulator connections. Then very very slowly open the active tank valve. Wait one minute. Then slowly open the valve to the other tank . Go to the stove and open the stove valve, you should hear gas flow.

[JRD]

DaveT... outside temps have been 80-90* days and 45-55* nights.

curver900... There probably is a tee buried behind the stove and fridge that serves both appliances. So why does the fridge work normally but propane flows to the stove only when the fridge is in “gas” mode? It’s a real head scratcher.

us71na... I’ll try this in the morning using your directions. I’ve already done something similar that didn’t help, though: closed the tank valves, disconnected both hose connectors to release gas in the lines, reconnected, then slowly opened the tank valves (active tank first then reserve tank).

Assuming the gas flow limiter is part of the tank regulator, wouldn’t it affect all of the gas appliances if it was tripped? Everything but the stove is working normally.

[DaveT]

Yeah so temp ain't the problem

[JRD]

I followed us71na’s directions exactly for resetting the main regulator/gas flow limiter with no result. Propane still flows to the stove only when the fridge is in gas mode.

When I switch the fridge to electric, the gas supply to the stove peters out after a minute or so. Similarly, when I switch the fridge back to gas mode, it takes a little while for gas to reach the stove burners so they can be lit.

Upon closer inspection, I see that all of the gas line junctions are surface mounted under the trailer and visible. They appear to be well connected with no breaks, gas odors, etc. Again, all gas appliances except the stove are working normally.

Could it be the stove’s gas regulator? Has anyone ever heard of one failing?

Other ideas? Thanks all.

[bankr63]

Does the stove work when the water heater is actively heating? Run the hot water until you hear the water heater ignite (or let it cool down a while with the burner off), then try lighting the stove.

I suspect that the problem is possibly with the regulator at the tank having an issue. With the stove alone there is possibly not enough demand and the regulator isn't allowing any gas to flow. Could be an old or damaged diaphragm inside the regulator. How old is the regulator? Mine seem to last 4 or 5 seasons with all of the heavy freeze/thaw over our Canadian winters.

The stove itself likely doesn't have a regulator as the actual pressure in the entire system is very low already from the 2-stage regulator at the tank.

[JRD]

I just fired up the water heater with gas, but there was no propane flow to the stove burner after leaving it open for two minutes. Seems to work only when fridge is in gas mode.

The gas lines to the fridge, hot water heater, and stove all branch out of the same junction block under the trailer which appears to be intact.

Tank regulator is only 2-1/2 years old.

Also FYI, this Atwood stove does have a small regulator where the gas line meets the burner manifold under the range top.

Geesh.

[ranchosinvacas]

Natural gas and propane gas each have a specific orifice depending on the type of fuel being used at the appliance. Is it in some way possible that the stove has an incorrect orifice installed? This is not likely, but it is in the realm of possibility....

[JRD]

Originally Posted by ranchosinvacas

Natural gas and propane gas each have a specific orifice depending on the type of fuel being used at the appliance. Is it in some way possible that the stove has an incorrect orifice installed? This is not likely, but it is in the realm of possibility....

No, because the stove has been working normally for the past 2-1/2 years. Thx.

[bankr63]

Final thought, if you switch the fridge to the electric with the stove lit, does it stay lit, or does it flame out?

Considering that it has been working for so long, there are only a couple of possible solutions, either a blockage/flow restriction in the line or a faulty part, but there are very few moving parts. Regulators have some moving parts, diaphragms and springs, that can break or leak. There is also the safety valve at the acme connector to the tank (but this could be isolated by swapping the tank in service if you have two). There are only a couple to spots to check.

The only other (cheaper) thing I can think of is to try to blow out the gas lines from the stove back to hopefully dislodge any foreign matter. But be careful with this as the system is designed for very low pressure (10"wc; less than 1 psi), so you run a real risk of possibly damaging something if you pump too much pressure in. I would disconnect the piping from the regulator and shut off supply at the WH and REF before trying such a thing.