Connecting to stove gas line for catalytic heater

[Trailbob]

I am installing a portable catalytic heater in our 25FC. I have identified the propane line that attaches to the stove as a good place to insert a tee for a separate line for the heater.

My question is: Can I connect a valve then a rubber propane rated hose (Camco, Sturgis, etc) and run it under the stove cook top, then route it behind the cabinets and out to a quick connect for the heater? My concern is whether it gets too hot under the stove top for a rubber hose. If it does, my second choice would be to run copper out the back, then put a shut off valve before the flexible rubber hose.

Also, I have used catalytic heaters for many years and am comfortable with the venting required for their safe use.

Thanks in advance- Bob

[idroba]

In general, there should be no fittings or connections INSIDE the trailer other than the one to the final device, which is why all the propane lines run outside under the belly pan, then run up to each individual appliance.

So, putting a T fitting inside in the line to the stove is not an approved way of making the connection. This is RV Code stuff, btw.

I also would not use a quick connect/disconnect inside the rig. I am not sure that is code legal either, but I simply don't trust the disconnect that well.

Sorry to rain on your parade but we want you around for a long time.

[nrgtrakr]

The funace in my 75 Overlander is under the range top just inside the door. The copper gas line to the furnace has a valved T. The valved side of the T goes to the furnace (so the furnace can be isolated). The other side of the T goes up over the furnace and down to a shut off valve then a hose to the catalytic heater.

Unless I'm confused, the catalytic heater, like the spare tire hanger, was an option during this time.

When I look at the propane pipe sizing charts for how big of gas line for how long of a run based on BTUs, everything is fine for both catalytic heater and furnace - that is they can both be on at the same time without any reduction in flame size.

The range top has its own branch. When I do the same BTUs to pipe size investigation for the range top, I see that the supply line is undersized which explains why the burner flames get smaller as you light more burners.

So what? It is likely that branching off of the range line will mean that you can only run one or the other, but not both.

When I get around to replumbing the gas lines on mine there will be no fittings inside other than point of connection, and the gas lines will be sized according to what they are supplying.

If any of this seems frightening, consider I was a career paratrooper while in the military, and in my (first) retirement was a stationary engineer (we plumb everything - water, steam, gas, liquid fuel - fiddle with electricity, electronics, and mechanical stuff and usually never blow up).

[HowieE]

Do it right. Put the Tee outside under the trailer and use copper piping to the heater. Use flared fittings.

I mounted my heater on the TV stand and had to run across the belly pan to the opposite side of the trailer.

[idroba]

Originally Posted by nrgtrakr

Unless I'm confused, the catalytic heater, like the spare tire hanger, was an option during this time.

I am pretty sure that Airstream never made a catalytic heater as a factory option, so yours was added at some point.

The reason I say this is that, although common, catalytic heaters are not approved for RV use as they are unvented. There is (or was) one which had an intake and exhaust vent and very small combustion fan which might have gained it RV approval, but I am not sure of that.

I am not wishing to start an argument for or against Catalytic heaters here, only stating why they are not used as standard equipment or factory option... because they don't meet RVIA code approvals.

[nrgtrakr]

There was RVIA code in 1975?

[idroba]

yes

[nrgtrakr]

Wonderful! Where can the current version be read? I've searched before with no results.

While a catalytic heater may not have been a factory option, pretty sure it was bought with it as the manual for the heater has the same scribbles as the original owners scribbles in other documents. Plus the data plate on the heater indicates it was made in 74. So perhaps a dealer installed option.

[idroba]

You might want to look at section 3 of this RVIA overview.

The Recreation Vehicle Industry Association: Standards

I do not have access to the actual documents as I am not a member. Lewster may have them but the outline of what is required is in the above specs.

A catalytic heater is an unvented appliance and as you can see in the outline, is prohibited by their standards.

[nrgtrakr]

Thanks!

Too bad they only provide an overview.

I remember one time Lewster said something about following yacht code as it was stricter more precise.

Kind of makes you wonder though how come almost every RV stuff sales place sells catalytics but never mentions NOT FOR INDOOR USE. Or says use indoors if permanently anchored.

In the places I've lived in Mexico, catalytic heaters are the norm for home use. But the building practices aren't exactly air tight.

[JCWDCW]

The PO installed a catalytic heater on our '96. It was as you want to do, tee'd off the stove with a shut of valve. Installer used copper all the way to the heater. Do it right as others are suggesting. Run copper all the way. Copper is more likely to survive an accident.

We run the catalytic heater with the front vent fan blowing 'in' on slow speed and let warm air drift to the back of the trailer and out the roof vent over the bed. This exceeds the recommended square footage of vent area stated on the heater and allows us to keep the whole trailer warm on brisk days.
JCW

[idroba]

I also will surely say I may be more concerned than others for this reason. There was a family tragedy involving CO gasses which killed my cousin, his wife and 3 year old daughter. Not in an RV, and a catalytic heater not involved, but CO can be really deadly, quite fast. You get a bad headache, stomach issues similar to the flu and don't go outside because you feel bad. You take in more CO and die, never knowing what hit you. They all died, one after the other, one night.

When I had a defective furnace in my '71 Caravel I kept getting headaches every time I used the heat when it was cool or cold outside. The windows fogged up more than they should of too. Finally dummy (me) realized that something was really wrong and I replaced the furnace. End of problem. I was glad there was not a 4th family member as a CO victim. BTW, CO alarms are now available, and I recommend one in your RV's. In the old days we didn't have them. Still, alarms fail too, and I would not use them as my primary defense against this deadly gas.

[nrgtrakr]

CO monitors can be beneficial.

Some small retreat cabins with propane stoves a few years after construction had some people want to use them in winter. They only wanted the ovens to make morning tea or coffee. The cabins were so air tight that the oven pilot alone was enough set the CO monitors off [the range top pilots were valved off, oven pilots typically have no shut off valve]. Hot plates were bought, distributed and gas tanks removed from the property. After the people left, all of the gas stoves were replaced with electric.

[AtomicNo13]

Originally Posted by idroba

I am pretty sure that Airstream never made a catalytic heater as a factory option, so yours was added at some point.

The reason I say this is that, although common, catalytic heaters are not approved for RV use as they are unvented. There is (or was) one which had an intake and exhaust vent and very small combustion fan which might have gained it RV approval, but I am not sure of that.

I am not wishing to start an argument for or against Catalytic heaters here, only stating why they are not used as standard equipment or factory option... because they don't meet RVIA code approvals.

In 1991, I had one installed on the line. It's on the curbside, from a tee. It has a shutoff valve, all on the outside of the belly pan.