Community Forums

CJ7365 · 02-21-2017, 09:18 PM

Took a look at my propane tank today, it looks like I am missing some kind of cap, I say that, because the inside threads look new and bright.

Does anyone know what this port is for, I did try a bing search, but nothing came up.

Does anyone have a picture or know what is missing and where to get one

Thanks in advance.

Old-Biscuit · 02-21-2017, 10:02 PM

That is the 'Relief Valve'
Missing dust cap.
Pointed down and out of propane compartment should it open due to overpressure

Use to have a picture of a MH tank with components...can;t find it right now so here is a diagram

CJ7365 · 02-22-2017, 09:49 AM

Quote:

Originally Posted by Old-Biscuit

That is the 'Relief Valve'
Missing dust cap.
Pointed down and out of propane compartment should it open due to overpressure

Use to have a picture of a MH tank with components...can;t find it right now so here is a diagram

Thanks Old Biscuit!!, was looking for a diagram, does it need a cap, piece of tape, or leave it alone?

Skip426 · 02-22-2017, 10:14 AM

JMHO: A piece of tape to keep debris out till you can locate the correct cap.

I'll check my tank and see if I have the same valve and a P/N on a cap.

twinboat · 02-22-2017, 11:44 AM

Here is a site that recomends a small bag and rubberband.

http://www.propane101.com/safetyreliefvalve.htm

theroc · 02-22-2017, 01:18 PM

Most likely you had a plastic dust cap covering the relief valve. I've attached what mine looked like and a close up of what you may want to purchase. The cap will "blow off" when needed if excessive pressure is present. Yours may have blew off entirely, tether and all.

Some tanks will have a hose attached to the valve to vent it away from the tank itself. Here's an old thread where a member is asking a similar question ...wondering what it was he was seeing coming out the bottom of his tank. At the end of the thread, it's concluded that it is a relief valve:

2005 Fleetwood Expedition 38N - propane line

.

firedoc · 02-22-2017, 01:37 PM

thisis not my picture or my unit but mine looks just the same. I was worried about a line that hung down under the tank and motor home that could be taken out by road debris. But it is an empty tube. Mine doesnt even have a dust cap on it. It exits by the rear duals. Just to keep the overpressure blowoff from being directed under the mh.

theroc · 02-22-2017, 02:07 PM

Quote:

Originally Posted by firedoc

thisis not my picture or my unit but mine looks just the same. I was worried about a line that hung down under the tank and motor home that could be taken out by road debris. But it is an empty tube. Mine doesnt even have a dust cap on it. It exits by the rear duals. Just to keep the overpressure blowoff from being directed under the mh.

Coincidentally, that photo is from the thread I referenced in my previous post. Yes, some tanks do have that setup that takes any bleed-off away from the tank area. No dust cap should be necessary at all in that scenario. And even if yours was partially taken out by road debris, I'm thinking it would not be that big of a deal in that the valve is still being protected from dust and debris.

The dust cap is probably not something that needs to be replaced immediately but as others have said, you would want something protecting the valve itself from getting clogged which is something that would in all likelihood take time to accumulate in order to clog the valve.

Old-Biscuit · 02-22-2017, 06:21 PM

A dust cap is nice to have to keep road debris out of area BUT if relief valve should open it will clear anything on it....they open at 300PLUS psi

twinboat · 02-22-2017, 06:50 PM

Quote:

Originally Posted by Old-Biscuit

A dust cap is nice to have to keep road debris out of area BUT if relief valve should open it will clear anything on it....they open at 300PLUS psi

They open at 300.1 psi. A slight leak can let debris into the sealing seat.

From the propane safety website if referenced.

A protective cover should be placed over the relief valve to ensure proper operation. If the valve has debris in the upper mechanism of the relief valve and it opens, the debris may cause the valve to remain open resulting in a potentially dangerous situation and/or excessive loss of propane. A simple protective relief valve cover can be made from a plastic bag fastened around the external portion of the valve with a rubber band.