2017 Thor ACE propane pressure drop

[martix_agnet]

I'm making this post for my wife, who is on a travel job and using our Thor ACE as her home.
She is having a propane pressure issue. She first discovered this when she returned to the RV after a few days and turned opened the propane tank valve to use it again. (she always closes the tank valve before she leaves for more than a day or so.) The propane tank shows full, and she has tried opening and closing the valve multiple times to make sure it's fully open.

She showed me a video where the interior stove lights at what appears to be full high flame, then it quickly dies down. At about medium setting, there's almost no flame at all.

She called me yesterday and said that when she was using her blackstone hooked into the outside line, she wasn't able to use the interior stove.
Today she calls and tells me she has almost no flame on the interior stove, even when when it's on high setting. She also says the blackstone grill no longer has full pressure either.

She removed the external propane line from the hookup outside the RV and the stove still has pressure issues.

Is anyone able to help us with this problem? The biggest issue is that I'm 4 hours away and unable to help solve it.

 

[16ACE27]

1 - Where is she located? There may be someone here that can do a quick recon.

2 - If 1 fails then call a mobile RV tech to go check out the RV (or just skip to this step).

 

[martix_agnet]

1 - Where is she located? There may be someone here that can do a quick recon.

2 - If 1 fails then call a mobile RV tech to go check out the RV (or just skip to this step).

She's in Southern Illinois.


I did some reading and we're going to give it time with the propane tank valve closed to see if it safety lockout system has limited propane flow. After reading more, we realized that can happen if a propane appliance is opened with the propane tank being closed. Hopefully she can try this before her night shift today so we can know what we're dealing with.

 

[ghnl]

After reading more, we realized that can happen if a propane appliance is opened with the propane tank being closed.

Does the 'fridge run on propane (if not on Shore Power)? If there was a power failure does the 'fridge automatically switch to propane?

 

[martix_agnet]

Does the 'fridge run on propane (if not on Shore Power)? If there was a power failure does the 'fridge automatically switch to propane?

It should auto switch to propane, you bring up an excellent point.

 

[16ACE27]

She's in Southern Illinois.


I did some reading and we're going to give it time with the propane tank valve closed to see if it safety lockout system has limited propane flow. After reading more, we realized that can happen if a propane appliance is opened with the propane tank being closed. Hopefully she can try this before her night shift today so we can know what we're dealing with.

How does the safety block explain the propane smell?
How does the safety block explain the stove lighting and burning fine at first but then lowering the flame?

 

[ghnl]

How does the safety block explain the propane smell?

Where did you read about a propane smell?

 

[16ACE27]

Where did you read about a propane smell?

It was in the original post before the original poster ninja edited it.

 

[GeorgePal]

How does the safety block explain the propane smell?
How does the safety block explain the stove lighting and burning fine at first but then lowering the flame?

I am thinking it is the safety block, but the block leaks a bit. She opened the tank valve and the block closed. It leaks a bit causing the interior lines to slowly come up to pressure. Light the stove, looks ok, drops down to minimal. This scenario happens on my rig if I open the propane valve rapidly after it sits for a while.

I open the p valve very slowly for the first half turn. Hasent happen since I started doing that.

 

[martix_agnet]

It was in the original post before the original poster ninja edited it.

I was hoping I caught that before anyone saw it.
The propane smell was from a second burner that she had opened and didn't fully close while she was attempting to find what the problem was. Once she closed the burner, the smell dissipated.

I am thinking it is the safety block, but the block leaks a bit. She opened the tank valve and the block closed. It leaks a bit causing the interior lines to slowly come up to pressure. Light the stove, looks ok, drops down to minimal. This scenario happens on my rig if I open the propane valve rapidly after it sits for a while.

I open the p valve very slowly for the first half turn. Hasent happen since I started doing that.

I'll give this advice and see what happens.

Are you able to explain how the safety block happens, and what monitors it? I assume it's "checking" for a leak in the system, or an open burner/valve.

 

[16ACE27]

I was hoping I caught that before anyone saw it.
The propane smell was from a second burner that she had opened and didn't fully close while she was attempting to find what the problem was. Once she closed the burner, the smell dissipated.

Whoops. That changes the trouble symptoms. Could be the safety stop, but since she turns the gas off all the time I doubt it, Why would it suddenly be a problem? They aren't prone to failure.

But the regulator is prone to sudden failure and may be the source of her problem as currently described.

 

[GeorgePal]

I was hoping I caught that before anyone saw it.
The propane smell was from a second burner that she had opened and didn't fully close while she was attempting to find what the problem was. Once she closed the burner, the smell dissipated.



I'll give this advice and see what happens.

Are you able to explain how the safety block happens, and what monitors it? I assume it's "checking" for a leak in the system, or an open burner/valve.

The block will stop the flow of gas if the flow rate exceeds what normal demands would be. So you should be able to run the stove, fridge, furnace at the same time, but if the line was broken, the gas would rush out. If the lines are depressurized, and you open the valve quickly, this rate can be exceeded for a moment while the rigs lines pressurize. This is what happened to me. Make sure the valve is off, all appliances are off. Wait a while (I don't know how long, I waited hours) and slowly open the valve. Purge the air from the line with the stove for a few seconds, and everything should work.

 

[martix_agnet]

Whoops. That changes the trouble symptoms. Could be the safety stop, but since she turns the gas off all the time I doubt it, Why would it suddenly be a problem? They aren't prone to failure.

But the regulator is prone to sudden failure and may be the source of her problem as currently described.

She closed the tank valve, let it sit for a while and then turned it back on. She said it worked to cook food on one burner. Later today she tried to use two burners and experienced the problem again.

I don't know if I'm going to able to talk her into replacing a regulator, but I'll give it a shot. This was my first guess before making this post anyhow. Is there only a single pressure regulator, or is there a high and a low?

 

[16ACE27]

She closed the tank valve, let it sit for a while and then turned it back on. She said it worked to cook food on one burner. Later today she tried to use two burners and experienced the problem again.

I don't know if I'm going to able to talk her into replacing a regulator, but I'll give it a shot. This was my first guess before making this post anyhow. Is there only a single pressure regulator, or is there a high and a low?

It's a single regulator, probably two stage. Not too difficult to replace but getting a mobile tech to do it may be the path of least resistance.

 

[martix_agnet]

It's a single regulator, probably two stage. Not too difficult to replace but getting a mobile tech to do it may be the path of least resistance.

I'm very much considering going to visit her this weekend or having a mobile/handyman tech come install it. I do need to get her more comfortable doing this like this though. She's perfectly competent, but the propane scares her.

I've found several models. Any idea which would be best? And am I going to have to adjust the output pressure on the one I install?
The Marshal Excelsior has lots of models, how do I know which one has the right output capacity?

Here is one a guy on youtube recommends. Is it $30 better?

Tractor supply also has one

I'm assuming any big hardware store also has them available.

 

[ghnl]

Did she switch off the 'fridge' (so that it won't be calling for propane when the tank valve is first opened)? Would that make any difference??

Our fridge has three options - Off, Auto, Gas. Auto uses 120V if available but 'automatically' switches to propane is 120V is not available.

 

[martix_agnet]

Did she switch off the 'fridge' (so that it won't be calling for propane when the tank valve is first opened)? Would that make any difference??

Our fridge has three options - Off, Auto, Gas. Auto uses 120V if available but 'automatically' switches to propane is 120V is not available.

This didn't change anything. She also got under the sink and took a look at the propane hoses to make sure they're not kinked.

 

[martix_agnet]

I ended up buying a Marshal excelsior MEGR-295P. Its rated for 175,000 btu, and from what I can find, the one installed is 165,000ish but. It should just be a 1:1 swap. It's seemingly a good middle ground in price and quality. Some of the once I found for sale look like junk and have reviews to support that.

I really would have preferred a higher flowing one just because they seem built better, but time is of the essence, and they wouldn't arrive until next week. This M.B. Strugis brand seems bomb-proof and offers 400,000 but output if necessary. Maybe next time I can see this coming before it happens, and order one of those instead.

 

[martix_agnet]

The regulator fixed the problem.

Thanks everyone!

 

[GeorgePal]

Glad you got it fixed!