Plumbing an External Propane Tank

[chroniekon]

I want to be able to live in my motorhome for an extended period of time. I have a 120 gal propane tank that is the fuel source for the furnace in my shop that I would like to connect to the motorhome. I have seen the Extend-a-Stay setups and understand that concept. My motorhome has a quick connect outlet for a grille. Can I run a hose from my external propane tank (downstream of it's regulator) and plug it into that grille quick connect and supply propane to the motorhome that way?

[A32Deuce]

That quick connect maybe low pressure from your units regulator. You would have to look and see where it ties in, either before the regulator(high pressure) or after the regulator( low pressure).

[chroniekon]

Yes the quick connect is low pressure and I would be feeding it with low pressure from the external tank.

[A32Deuce]

Need to know the pressures of the regulators first.

[chroniekon]

The external tank regulator label says 9.5-13" WC. There are no tags or labels on the Motorhome regulator, so not sure, but some looking online says 11" WC is common.

[TitanMike]

Only real reason not to "back feed" the propane system with low pressure gas through the grille QD is pressure loss over any distance. If the large supply tank is close, probably no big deal. If not, better to feed high pressure from Aux tank valve directly to one of the pigtails that connects to the vehicle mounted tanks.

This way the LPG is transported to the regulator and the distributed from there.

[Mrprovy]

Why not disconnect your on-board and run an extension from the 120lb tank to your regulator?

https://www.amazon.com/dp/B07KF7LSQN..._vUFYDb32PNAZP

[chroniekon]

Originally Posted by TitanMike

Only real reason not to "back feed" the propane system with low pressure gas through the grille QD is pressure loss over any distance. If the large supply tank is close, probably no big deal. If not, better to feed high pressure from Aux tank valve directly to one of the pigtails that connects to the vehicle mounted tanks.

This way the LPG is transported to the regulator and the distributed from there.

I would need to go 15 feet or so.

[chroniekon]

Originally Posted by Mrprovy

Why not disconnect your on-board and run an extension from the 120lb tank to your regulator?

https://www.amazon.com/dp/B07KF7LSQN..._vUFYDb32PNAZP

That is a possibility. My fittings look different than that I think. It sounds like I may need to go to a propane supply business.

[br23mat8]

Be sure the extention hose can handle propane from 120 lb source.

[Lake5er]

I had a tank added to my stationary 5th wheel so I would have to deal with pulling and filling the 30 gallon tanks. I let the propane company do the hookup to the trailer to guarantee a safe connection and proper install. They charged parts and a small fee, but well worth the piece of mind.

[5picker]

To answer your question, yes it will work as long as you regulate the tank you are using to feed the low pressure disconnect.

It has been reported here several times the factory (in some divisions) use the low pressure disconnect and a portable tank to test the LP system during manufacture. You may want to close the valve on your on-board tank if you want to keep that as a reserve.

[DrLewie]

Originally Posted by Lake5er

I had a tank added to my stationary 5th wheel so I would have to deal with pulling and filling the 30 gallon tanks. I let the propane company do the hookup to the trailer to guarantee a safe connection and proper install. They charged parts and a small fee, but well worth the piece of mind.

I agree with this completely. Propane is dangerous and if you aren't certain you know what you're doing, have a pro do it.

[jkoenig24]

It's EASY to get this wrong. As I understand it, propane should only be regulated ONCE. Start by watching the RVGeeks YouTube video. Then talk with a CERTIFIED propane professional.

https://www.youtube.com/watch?v=jovTYfltUO0

[gasman6674]

Back feeding thru the grill low pressure quick disconnect will work maybe. Maybe because the line size and length from your 120 may not be big enough in id or too long for the id to handle your load. If it is properly sized it will work. the existing regulator should remain closed (no flow) because of the downstream pressure however I would close the tank valve also. You might do this if you are not going to be on-site all winter. The most common practice in the field is to replace the existing inlet "pigtail" with a longer one and direct feed high pressure into the existing system. Your supplier can set you up with the correct system for your area as he is ultimately responsible as he supplied the gas.

[chroniekon]

Thanks for all the suggestions everybody. I went to a local propane supply place yesterday and was able to see an Extend-a-Stay setup. My initial concern with using this device was it's size. I don't have very much room to install this device. That's why I was looking for an alternative method to get gas to my rig. After seeing it, it is much smaller than it looks in the pictures and I think it will fit just fine. The other issue I have, there is an earthquake shutoff valve on my external tank, so no premade hose has any of the right fittings on them. The propane supply place can make me a hose with the ends I need.
It's going to be a week or so before I get everything installed (hopefully) but I'll update with some photos then.

So a word on the earthquake shut off valve. I live in the Northwest. They say we're sitting on a potential 9 earthquake. While the device isn't required here in Oregon yet, I think it makes a lot of sense to have. I also have one on my natural gas meter for the house.
https://www.faucetdepot.com/faucetde...yABEgIfkvD_BwE

[MnTom]

Originally Posted by jkoenig24

It's EASY to get this wrong. As I understand it, propane should only be regulated ONCE.

Sorry, but most all home tanks have two regulators on the system. There is a red colored high pressure regulator that take tank pressure and regulates it down to 5 psi. From there the line runs to the side of the house to a brown colored regulator. That one drops the 5 psi down to 11 inches of water column(just under 1/2 psi). You can get a residential regulator that is called a two stage, but the distance from the tank to the house can be a problem at low pressure.

[chroniekon]

So my final setup is an 'extend-a-stay' at the motorhome end (picture 1). I had to add an elbow to the downstream side of the regulator to get enough room to make it all fit. I also added a bracket to support the regulator as I had read a few reviews that said they had trouble with the extend-a-stay breaking. I was hoping for a 20' hose, but the longest hose the propane store would make was 15', apparently the gas can re-liquify in certain conditions with a long hose. I was not able to have the earthquake valve right at the tank because they are only rated for 5psi and it has to be located downstream of the regulator (picture 2). The tank end of the hose has a standard left hand thread propane tank end on it and takes the place of the copper tube that feeds my shop furnace when in use as an external tank for the motorhome (picture 3)