Will install Platinum Cat heater, trying to figure out what fittings I need. With trailer being in Mexico, it's easier to bring all the parts from the US or Canada.3/8 OD copper pipe going from under-floor iron pipe to gas range and other appliances is a nominal 1/4 ID, right? So here is how I see it - for above the floor section. Correct me if I'm wrong:1) 1/4 ID copper pipe exits the floor inside and will have 1/4 compression x 1/2 FPT- with compression going onto the copper pipe.2) 1/2 FPT of part #1 goes onto the 1/2 MIP of 1/2 MIP x 1/2 MIP stainless 24" gas appliance connector - with excess flow valve included, it works like a shut-off valve. I could've just run the 1/4" pipe all the way to heater, but this 24" connector will make routing easier, and it has a valve.Corrosion Q:On brass compression fittings Home Depot has a warning "not to use on stainless tubing". I know about corrosion of dissimilar metals - is this really a problem? This warning is on compression only. That gas appliance connector is stainless, with brass excess valve - and there is no warning. Also, black iron pipes below, exposed to elements, have brass Tees where 1/4 copper pipe is connected - and they didn't see it as a problem. So there is no problem with stainless connector?3) 1/2 MIP end of the connector #2 goes into the FIP end of 1/2x3/8 FIP coupling. 3/8 FIP end (NOT flared) goes onto 3/8 male flared end of the heater. I couldn't find a coupling 1/2 FIP x 3/8 female flared - is this a problem?Not being a gas fitter I could've missed something - maybe a lot. Any criticism is appreciated. In a small Mex town it's better to understand what needs to be done and how, even if you hire somebody.

To cut to the chase...Stop in at your local LPG supplier the folks who deliver LPG to homes, and service appliances. They will offer crucial tips and hints as to what you need. The critical link IMO is the FLEX hose interface between the manifold supply and the unit. ALWAYS install an accessible low pressure shutoff valve where you can get to it inside the rig but NOT right against the heater. I have had nothing but problems with copper lines so they are on my BANNED list. I rather ran schedule 40 black iron pipe as the feeder beneath the rig. You might want to think about installing a FILTER somewhere. Mexican distributors rarely flush out refiner's lube oil, or excess odorant (an oil) and either can screw up LPG appliance controls.

Compression connections are not used on gas- only flair or inverted flair. I also wound not use those gas appliance connectors- they really are not meant for constant movement and vibration. A flex rubber line is what you want.Last- no, you cannot hook a pipe to a flare fitting- it will not be gas tight.

Does the heater have an oxygen depletion sensor? If not it is not safe for your use inside your trailer. Also if the heater is not approved for mobile home use I would not use it. As said before flare fittings are the best for copper tubing compression is only use for pilot lines.Good Luck

I plumbed 2 Olycat heaters in my motorhome using brass barbed fittings, and all 1/4" clear vinyl hose from our local hardware store, w/ the small fuel line clamps. Talk about an easy job, no question. Yep, I did my research, its all legal and working fine for 2 yrs now.

That looks like a nice heater (assuming you are getting one of the RV ones). I would think that a vented catalytic heater would work really well.Where is the regulator on this- are you doing a high pressure or low pressure run?Only use propane-rated fittings!

Propane plumbing - adding cat heater | Good Sam Community

Almot
Explorer III
Apr 11, 2014
beemerphile1 wrote:
Easiest way to tap the existing system may be by using an existing connection at another appliance. Install a tee in place of existing fitting and run your new line from there.

This is exactly my plan. There is a tee already on iron pipe, with 3/8 copper branching out to my (much hated) furnace. Being away from the trailer now, I'm scratching my head trying to recall if this is a regular FIP tee and how the heck they connected 3/8 to it :)... It looks like the tee has to stay, and another tee needs to be added.

mlts22 wrote:
...it won't hurt to add a valve on the line coming from the tee. This way, the heater can be disconnected without affecting everything else on the propane lines.

Jeez, I agreed to the valve already :)
mlts22
Explorer II
Apr 11, 2014
beemerphile1 wrote:
Easiest way to tap the existing system may be by using an existing connection at another appliance. Install a tee in place of existing fitting and run your new line from there.

In addition to that, it won't hurt to add a valve on the line coming from the tee. This way, the heater can be disconnected without affecting everything else on the propane lines.
beemerphile1
Explorer
Apr 11, 2014
Easiest way to tap the existing system may be by using an existing connection at another appliance. Install a tee in place of existing fitting and run your new line from there.
Almot
Explorer III
Apr 11, 2014
Westend - dinette bench has a removable top. It's easier to go outside and shut the tank than getting to the valve under the bench. This is why I like Brasscraft excess flow valve - it's an automatic valve. Can use both, of course.

Pdogg - yes, 3/8 copper all the way was my initial plan.

Incidental question: what is nominal size of black iron pipe under the floor? By the outside measurements it looks like 1/2 ID, but I could be wrong. Like this schedule 80.
pdogg
Explorer
Apr 10, 2014
Almot wrote:
pdogg wrote:
I added CAT heater by putting a black pipe fitting to flare 3/8" copper tubing. Tubing run unto interior compartment, where I put a gas rated ball valve with flare connection. Rubber hose to propane quick disconnects from there.

This is what I'm trying to figure out - what parts should I get. For now, only talking about above the floor part.

So there is a bare end of 3/8 OD copper pipe sticking out of the floor inside, in the "interior compartment" - under dinette bench. The heater is about 2ft away. What parts do I need to get from the bare copper pipe to 3/8" flare of the heater?

Rubber hose inside is not safe - technically, but still an option if nothing else will do, and it is easy. A piece of 3/8" copper sounds better for this purpose - more difficult, yes.

Go copper all the way... I did rubber with disconnects since my heater is portable and I like to put it away.
westend
Explorer
Apr 10, 2014
The minimal would be a flare union to answer your connectivity question, along with another length of 3/8" copper and the proper fittings. It is a good spot for a shutoff valve, though, even if it has poor access. Do your dinette benches have a removable or hinged bench top?
Almot
Explorer III
Apr 10, 2014
pdogg wrote:
I added CAT heater by putting a black pipe fitting to flare 3/8" copper tubing. Tubing run unto interior compartment, where I put a gas rated ball valve with flare connection. Rubber hose to propane quick disconnects from there.

This is what I'm trying to figure out - what parts should I get. For now, only talking about above the floor part.

So there is a bare end of 3/8 OD copper pipe sticking out of the floor inside, in the "interior compartment" - under dinette bench. The heater is about 2ft away. What parts do I need to get from the bare copper pipe to 3/8" flare of the heater?

Rubber hose inside is not safe - technically, but still an option if nothing else will do, and it is easy. A piece of 3/8" copper sounds better for this purpose - more difficult, yes.
pdogg
Explorer
Apr 10, 2014
I added CAT heater by putting a black pipe fitting to flare 3/8" copper tubing. Tubing run unto interior compartment, where I put a gas rated ball valve with flare connection. Rubber hose to propane quick disconnects from there.
Bob_Landry
Explorer
Apr 10, 2014
Almot wrote:
Thanks, guys. Will try and avoid straight pipe fittings. More questions:

1) Straight FIP: click on the video at bottom of the page for Brasscraft excess flow valves - they connect male flare of the excess flow valve to straight FIP of the shut-off valve. (Must be straight FIP because shut-off valves only have FIP or male flare).

2)
Chris Bryant wrote:
Compression connections are not used on gas- only flair or inverted flair.

What would be the right fitting to put on 3/8 OD copper pipe then? I mean, on the "copper" end.

3) Low pressure or high pressure. It will be from tall 70 lbs cylinder. Being a seasonal camp - possibly will install stationary tank in future. Either scenario will include a propane regulator that originally came with trailer, and I "think" this is called low-pressure. Or not?

4) Shut-off valve in easily accessible location - I'm hearing this all the time, but "easily accessible" is difficult in my case. The whole 2ft run from copper feeder pipe to the heater will be under the dinette bench, exiting out of the bench few inches from the wall-mounted heater. Shut-off valve under the bench? no, thanks. It will be easier to go outside and shut off the valve on the tank. Then I can unscrew the line from the heater and put a plug on it. Meanwhile, excess flow valve between the copper feeder line and heater will shut it off if there is a rupture downstream.

5) Mex: what problems did you have with copper tubing? Also, any links to inline propane filters?

To the OP..

I can't imagine what problems Mex has had with copper tubing. Trailer manufacturers have been using it for years. If the connections are properly done and tested for leaks, and the tubing is secured so that it does not vibrate and rub against anything, it should provide a lifetime of service.
Copper tubing is easily mated with black pipe if the proper fittings are used. Black pipe and copper gas fittings all use NPT threads and any fitting will mate with a black pipe coupler, Tee, Ell, or Street Ell of it's same thread size. The threads need to be sealed with pipe dope or yellow thread tape made for gas. Flared fittings are easy if you have done them before, if not it can be an exercise in frustration. It's not rocket science, but it does take a certain amount of knowledge.
After reading this thread a couple of times, my comments are meant as constructive and not condescending so please tale them as such.. Given your lack of knowledge on this subject and with no experience working with LP systems, I would enlist the help of someone who is knowledgeable in working with propane systems. It's not like miswiring something where you reset a breaker and get another chance to do it right. While propane is for the most part a perfectly safe cooking and heating fuel, a mistake while handling it or putting together a delivery system can be catastrophic, and you may not get a redo.
Almot
Explorer III
Apr 10, 2014
Thanks, guys. Will try and avoid straight pipe fittings. More questions:

1) Straight FIP: click on the video at bottom of the page for Brasscraft excess flow valves - they connect male flare of the excess flow valve to straight FIP of the shut-off valve. (Must be straight FIP because shut-off valves only have FIP or male flare).

2)
Chris Bryant wrote:
Compression connections are not used on gas- only flair or inverted flair.

What would be the right fitting to put on 3/8 OD copper pipe then? I mean, on the "copper" end.

3) Low pressure or high pressure. It will be from tall 70 lbs cylinder. Being a seasonal camp - possibly will install stationary tank in future. Either scenario will include a propane regulator that originally came with trailer, and I "think" this is called low-pressure. Or not?

4) Shut-off valve in easily accessible location - I'm hearing this all the time, but "easily accessible" is difficult in my case. The whole 2ft run from copper feeder pipe to the heater will be under the dinette bench, exiting out of the bench few inches from the wall-mounted heater. Shut-off valve under the bench? no, thanks. It will be easier to go outside and shut off the valve on the tank. Then I can unscrew the line from the heater and put a plug on it. Meanwhile, excess flow valve between the copper feeder line and heater will shut it off if there is a rupture downstream.

5) Mex: what problems did you have with copper tubing? Also, any links to inline propane filters?

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