My original Manchester #6820 LP tank developed its second leak around the threads for external fittings. First it was the port for the pressure relief valve and now the port for the level gauge. That’s two leaks too many so time for a new tank, especially since the original passed its 16th. birthday.
My online research endorsed the Manchester #
6817 12” x 32” tank selected by
autox as a direct bolt on unit having the best compromise in size, weight and capacity. Our road trip style never required the full capacity of the original tank so any opportunity to save weight was welcome.
1. DELIVERY of NEW TANK
I purchased directly from Amazon who promptly delivered a new #6817 Manchester tank by FedEx. Amazon’s tentacles are now into everything and make supply to the end user far more convenient. When I inquired about getting a new tank a few years ago I was told I could only proceed through an authorized Manchester dealer and submit to their professional installation. Good luck finding one in the Arizona outback, where DIY rules the day.
2. REMOVAL of OLD TANK
Just my luck the leak was detected with an almost full tank, so the combined weight of tank + propane was around 140 lbs. First step was to attach a grounding strap as leaking propane made me overly cautious. Then I judiciously placed ramps and blocks to slide the behemoth down after removing four 1/2” bolts securing the frame brackets. There was just sufficient clearance under the fiberglass skirt to roll the tank out without jacking up the vehicle.
So far so good, but now I had to burn off the propane to prepare the tank to be accepted as safe scrap. This took nearly 4 days using a single burner turkey fryer supplied by single-stage regulator. Then I removed fill valve, supply valve and overpressure relief valve for permanent venting. These large fittings were most stubborn and needed a large breaker bar. Finally I filled the tank with water to displace all propane vapor. Even so the stench of mercaptan odorant persisted.
3. PREPARATION of NEW TANK
First I attached the two frame brackets to the shiny new tank as they are hard to reach in place under the RV to tighten up to ~ 60 ft.lbs. Then I laid the assembly flat on a stiff cardboard sheet to make a template with bolt holes cut out. The horizontal bolt spacing was 23 1/2” and the template enabled me to mock-up the best position along the chassis frame rails without interference.
4. PREPARATION of MOUNTING AREA
I also had to remove the galvanized sheet metal exhaust heat shield to cut new slots to pass through the lower mounting bolts for the shorter tank. The cardboard template was again most handy to scribe the sections to be cut out with a Sawzall.
5. INSTALLATION of NEW TANK
Fortunately the lighter tank was easier to handle but still needed blocks and a jack to position so the mounting bolts lined up. This became quite fiddly writhing under the RV and an LED work light became essential to line up the bolt holes. If only I had three hands!
Naturally the tank was delivered containing air and had to be purged properly before the first fill, that turned out to be 12.2 gallons. I left this up to my LP professional at the filling station as he had the suitable hoses and years of experience. It was a pity I couldn’t recover my old propane but I suspect it was contaminated by water and air.
6. FITTINGS
I also purchased a new Manchester G12846 Remote OHM Sender level gauge that simply snaps into place after being spliced into the existing wiring. Fortunately there is no polarity to figure out as the gauge is a simple rheostat. Imagine my surprise then when it read Full on an empty tank! The gauge works by magnetic coupling and the magnets were simply 180 out of phase, so I spun them another half turn with a small bar magnet.
The new tank came with a vertical vapor delivery port, unlike the old where a two-stage regulator could be screwed sideways into the tank for a horizontal mount. I called Manchester who strongly advised against tightening the tank fitting another 90 degrees so I had to devise another way to mount a horizontal regulator. Of course a 90-degree elbow would work but I preferred to locate the new regulator higher up away from road debris. To this end I fabricated a sturdy metal bracket to bolt the regulator on an unused upper tank mount (above liquid propane level) and had hoses fabricated to the proper length for inlet/outlet.
7. TEST
All fittings were bubble free when tested, the level readout on the display panel above the stove was correct and the burners operated with a strong, clear blue flame. The furnace fired right up and delivered good heat. Ahhh, the hiss of reliable gas on tap again for a good cuppa tea…
8. SUMMARY
Hopefully this long -winded post may encourage others who eventually need to change out their propane tank at home. The job is not too complex but requires time, patience and strict attention to s-a-a-a-f-e-t-y. I found the following two references confidence inspiring.
9. REFERENCES
http://www.propane101.com
and
http://www.gasequipment.com/catalogs/Ca ... -Hoses.pdf