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Re: Quote for propane install

PostPosted: Wed Apr 15, 2015 10:49 am
by zroadhouse
I got another estimate from a local RV shop on the work @ 6 hours of labor - $120/hr + $180 in parts = $900. Much better than the first estimate. The gentleman I talked with stated that on a short run to a single device that we could use a single stage regulator and a rubber hose into the trailer. I'll have to think about that option.

I think I'm getting more comfortable with the idea of doing it myself and hiring someone to do an inspection on the system.

Re: Quote for propane install

PostPosted: Wed Apr 15, 2015 10:51 am
by zroadhouse
bobhenry wrote:Here is a further explaination of the drip leg.

I had problems with this fireplace




and finally called in professional help. The furnace guy was even almost at a loss. He was finally convinced the orifice was clogged. I stripped a very fine stranded wire and pushed it thru the opening. I couldn't tell any difference but we reinstalled it and it worked. He pointed out that my 1/2 steel threaded pipe goes directly to the flex gas line. He suggested I re-plumb slightly by removing the upsweep ell and replace it with a tee fitting and add a 4-5 inch nipple with a cap pointing down. This "drip leg" gives a place for heavy particles to fall and get out of the gas flow. Seems the rust and crud in the pipe just needed a place to get away.


Can you post a picture? I'm trying to visualize what you are talking about.

Re: Quote for propane install

PostPosted: Wed Apr 15, 2015 4:16 pm
by Treeview
Maybe a description will work?

Main gas line comes in from the right...at 3 o'clock.

Main line is attached to a T fitting, at 3 o'clock.

Short pipe nipple is installed at 6 o'clock and capped.

Gas line exits at 12 o'clock.

Take a look at your house water heater or furnace, you'll see the T.

Tom

Re: Quote for propane install

PostPosted: Wed Apr 15, 2015 5:33 pm
by MtnDon
There are drip legs and there are sediment traps. Similar but different.Link with explanation and pictures.

Drip / sediment traps have a varied history. They have come and gone in different versions of codes and can differ with geographic location and with propane vs natural gas. We built our home in the mid 80's. No drip or sediment traps needed. Now if we installed a new gas appliance or furnace we would need a sediment trap. But no need to retrofit on the old existing equipment. Traps can do good, can prevent problems, they do no harm, so installing a sediment trap could possibly head off a future problem.

Re: Quote for propane install

PostPosted: Wed Apr 15, 2015 5:59 pm
by zroadhouse
Got it. A little googling on "gas drip leg" helped.

Here's my attempt at a verbal description of the system (will draw and post in a bit):

On the front of the trailer:
  • 20# Bottle in mount on the front of the tongue
  • ACME connector high pressure pig tail from bottle to valve (about 3-4' running along the tongue frame and up to the right side of the regulator) (still looking for a part)
  • valve
  • Two stage horizontal regulator mounted on front of the trailer (1/4" NPT inlet, 3/8" NPT outlet) (inlet is at 3 oclock - outlet at 6)
  • 3/8" NPT black pipe nipple (a few inches?) (from 3 oclock to 9 oclock)
  • 90 deg reducing elbow (3/8" to 1/2") (from 3 oclock to 6 oclock)
  • 1/2" NPT black pipe (~18") (from 12 to 6 oclock)
  • 90 deg elbow (1/2") (heading towards the back of the trailer - 3 oclock is now front of the trailer)
  • 1/2" NPT black pipe (~3') (from 3 to 9 oclock) (attached to cross members with hanger straps)
  • 90 deg elbow (1/2") (from 3 to 12 oclock) (pointing up towards the floor of the trailer)
  • 1/2" NPT black pipe (2') (from 6 to 12 oclock) (grommets around floor and cabinet entry)
  • 90 deg elbow (1/2") (from 6 to 9 oclock)
  • nipple to T with 3" down nipple with cap (from 3 to 6 and 9 oclock)
  • valve
  • flex line to burner (from 3 oclock up)

Re: Quote for propane install

PostPosted: Wed Apr 15, 2015 6:21 pm
by zroadhouse
Here are the drawings of my proposed system:
130744
130746

Re: Quote for propane install

PostPosted: Wed Apr 15, 2015 6:47 pm
by MtnDon
The valve between the regulator and the cylinder is not needed. The cylinder has a shut off and that is all you need before the regulator. You use that to shut down the gas supply.

OTOH, when or if there are more than one appliance (range, furnace, water heater, etc.) a valve just before the connection to the appliance can be handy in case service is required. That can avoid shutting down the whole system if one piece needs work.

Re: Quote for propane install

PostPosted: Wed Apr 15, 2015 7:13 pm
by zroadhouse
MtnDon wrote:The valve between the regulator and the cylinder is not needed. The cylinder has a shut off and that is all you need before the regulator. You use that to shut down the gas supply.

OTOH, when or if there are more than one appliance (range, furnace, water heater, etc.) a valve just before the connection to the appliance can be handy in case service is required. That can avoid shutting down the whole system if one piece needs work.


Ok - cool. I included a valve before the appliance since I figure that will make it easier to test the system in pieces (I can test the pipes for leaks before hooking up the cooktop).

I was realizing that I could also change the drip leg into a sediment trap by changing the orientation of the T.

Re: Quote for propane install

PostPosted: Wed Apr 15, 2015 7:21 pm
by zroadhouse
Though I did read this while doing some more searching on the net:

G2419.4 Sediment trap. Where a sediment trap is not incorporated as part of the gas utilization equipment, a sediment trap shall be installed downstream of the equipment shutoff valve as close to the inlet of the equipment as practical. The sediment trap shall be either a tee fitting with a capped nipple in the bottom opening of the run of the tee or other device approved as an effective sediment trap. Illuminating appliances, ranges, clothes dryers, decorative appliances and outdoor grills need not be so equipped unless specifically required by the appliance manufacturer's installation instructions.


Even though its not required, is it still a good idea?

Re: Quote for propane install

PostPosted: Wed Apr 15, 2015 8:02 pm
by MtnDon
Considering that homes only require them at furnaces and water heaters I am comfortable not having one at all on a trailer. For whatever the reason is for homes, the distinction seems to be made on whether or not the gas appliance turns itself on and off, as a thermostat controls a furnace or water heater.

We don't have one on our trailer, FWIW.

Re: Quote for propane install

PostPosted: Thu Apr 16, 2015 11:18 pm
by capnTelescope
I included a drip leg in my piping install. It's in this post.

It looks like this:
ImageThe end on the right is the drip leg and points down. The tee gets the pipe from the tank. The other nipple goes up to my appliances.

Note the yellow pipe goo. That's the kind they want you to use for gas pipe sealant. It'll say its for natural and LP gas. Works for water, too. :)

Re: Quote for propane install

PostPosted: Thu Apr 16, 2015 11:32 pm
by zroadhouse
Is the leg part under the trailer and pointing down in your install?

capnTelescope wrote:I included a drip leg in my piping install. It's in this post.

It looks like this:
ImageThe end on the right is the drip leg and points down. The tee gets the pipe from the tank. The other nipple goes up to my appliances.

Note the yellow pipe goo. That's the kind they want you to use for gas pipe sealant. It'll say its for natural and LP gas. Works for water, too. :)

Re: Quote for propane install

PostPosted: Thu Apr 16, 2015 11:57 pm
by capnTelescope
zroadhouse wrote:Is the leg part under the trailer and pointing down in your install?

That is correct. It's vertical. Actually, the tee is underneath, too. The other nipple comes up through a hole in the floor THAT STILL NEEDS CAULKING! :fb

[edit] My tee is underneath. Yours doesn't have to be. [/edit]

Re: Quote for propane install

PostPosted: Fri Apr 17, 2015 10:41 am
by zroadhouse
On my trailer if I did the T that way, the trap nipple would protrude under the frame. :oops:

Hopefully I'll get to this this weekend.

Re: Quote for propane install

PostPosted: Fri Apr 17, 2015 11:53 am
by bobhenry
This helps to picture the thoughts in my original post

Here I have oriented the picture in as near upward as I could.
The red lines are cut lines showing a very short nipple replacing both sections.

Image

The down leg will collect about as much debris as the amount of black pepper you put on your eggs.
A huge volume is not needed just a place for it to fall out of the flow of gas. Most gas lines have male thread so a coupling can be added to the top. Again by having a very short nipple between the top of the tee below the floor and the coupling above your gas line is well supported if you kept the hole just big enough for the pipe itself.