Mobile propane question

Working on propane in an RV. Starting from scratch.

Plan is two 20lb bottles with an auto changeover two-stage regulator, black pipe back to near the appliances (water heater, stove), shutoff valve and braided stainless hose to each of the appliances.

Picked up an antique natural gas stove and am planning to convert to propane. Everything I've read says to convert, you need to change the regulator on the stove to propane settings and swap the orifices for propane-sized ones. 

If I'm running a regulator at the bottle, do I need a regulator at the stove?

The propane regulator should be fine if its the right pressure for the appliances.  I don't think RV regulators are anything special, and I don't think RV appliances use different pressures than, for instance, a home grill.  That means they should be compatible.

I strongly recommend not using black pipe except for main distribution.  One, well-supported straight line of iron down the frame rail is fine, but RVs are subjected to constant shaking, twisting, and vibration.  For this reason, most RV manufacturers use malleable soft copper.  If you plumb it all with threaded iron, the joints will start leaking sooner than you think.

Both of my current RVs have one straight 1/2" black pipe mounted to the frame rail with fittings that tee off to flare.  From there, it's all copper up through the floor all the way to the appliance.

Can't stress enough... on both the iron and the copper.... support, support, support.  I would guess the largest span without a rubber-lined clamp (at least on my Keystone 5th wheel) is 8" on the copper and 24" on the iron.

Look up the RVIA standards.  I found a book to buy here, but you might find them on the googles.

In reply to Curtis :

Yeah, that's the intent, one straight run of black pipe down the frame rail with lots of supports. I should be able to support every 12" easily.

Thanks for the feedback on the regulator, that's what I thought.

Yes once its through the reg its low pressure, as long as all your appliances are low pressure your good to go. 

JohnInKansas said:

In reply to Curtis :

Yeah, that's the intent, one straight run of black pipe down the frame rail with lots of supports. I should be able to support every 12" easily.

Thanks for the feedback on the regulator, that's what I thought.

Good.  The intent is for any branches to be incapable of exerting torque on the main trunk.  Copper or other soft line prevents that.

In reply to Curtis :

I appreciate you saying that. Looking at my scribbled diagram, I was definitely going to have a run that would have been able to exert torque on the main. I'll either use a longer braided stainless hose or use a short braided stainless hose to connect the arm to the main.