Installing propane tanksJan 1, 2003
Happiness is a propane gas stove. When we first became serious about living aboard Endeavor, our vintage Tartan 34, we read all the traditional liveaboard books and decided on a pressurized kerosene stove. It turns out the chief attribute of the stove we chose was appearance; it was the prettiest traditional-looking stove we had ever seen, and it fit the space available.
In actual use, however, this stove was the cause of more headaches than any other piece of equipment on the boat. The stove did give us an opportunity to meet Nigel Calder in Salinas, Puerto Rico, when he came to our rescue with a can full of stove parts as I was struggling to make the stove work. After rebuilding everything on the stove during a period of 10 years, we gave up and decided to switch to gas.
As most of us know, there are serious safety considerations with propane gas on a small boat. Propane gas is heavier than air and must be vented overboard. The biggest single problem is where to locate the propane tanks so that they are ventilated properly and gas can be switched off at the tank. While most larger, newer boats have built-in propane lockers, a vintage boat like our Tartan does not. The standard, commercially available two-tank lockers are great, but they take up lots of room; room we just don't have. Besides, I don't like cutting big holes in the deck for the locker and an overboard vent in the topsides. Like most sailors I thought about the problem and crawled around the boat for hours with a tape measure trying to find a place for the tanks. I ruled out locating the tank locker on deck. I soon gave up on using 20-pound tanks; they were just too big, and commercially available lockers were nearly the same size as our diesel engine! We thought 10-pound tanks would work, so we talked to our liveaboard friends; a 20-pound tank only used for everyday cooking lasted about eight weeks, so we figured a 10-pound tank should last four to six weeks. Since propane gas is available nearly everywhere on both sides of the Atlantic and the Islands, this length of time on a tank of gas is acceptable (assuming we always carry a spare). It turned out for us that a 10-pound tank lasted at least six weeks with everyday use.
The stove itself was the least of the problem. We chose a stainless steel Tasco two-burner stove with a decent-sized oven mainly because the price was right, it had a temperature-controlled oven, it fit the hole left by the old stove, and we've had good luck with our Tasco gas barbecue grill. Besides, we could get rid of the kerosene pressure tank and alcohol primer. Now all we needed kerosene for was the lanterns we use below.
It turns out two 10-pound tanks will stand upright on the slightly rounded section of the stern on either side of the backstay without the use of a propane tank locker. Venting overboard was not a problem with the tanks mounted on the stern. I bought two, 10-pound aluminum tanks, a regulator, a regulator cover and a brass remote-control solenoid knowing that they were going to be exposed to the weather. When the parts arrived I placed the tanks on the stern, measured them several times, and tried to figure out how I could attach them upright. They had to be mounted strongly enough so that a large breaking sea (which has never happened in 20,000 nm) would not tear them off and knock them overboard. I assumed we would have to put up with the two ugly tanks on the already cluttered stern. Ten-pound tanks are 10 1/2 inches in diameter at the widest point and about eight inches in diameter at the base. Two one-inch-thick, 10 1/2-inch-round bases were madeone for each tankout of mahogany by a local cabinet maker. A 1/2-inch-deep-by-1/2-inch-wide groove was routed in each base to accept the round base rim of the tank, the tank base being smaller than the overall tank diameter. Since the stern was rounded, the bases were slightly concave so that they would lie flat on the stern. The bases were given five coats of varnish before being installed in place. A small, 3/16-inch drain hole was drilled from the groove to the low point on the outside of each base. The starboard side tank was to be the active tank with the port tank as spare; the stove is located on the starboard side. The active tank had the gas regulator and remote gas solenoid assembly mounted on an aluminum upright, two inches wide by 1/4 inch thick by 14 inches long, bent at right angles three inches from one end. The three-inch end of the upright was made to fit under the outside of the starboard base. A two-inch-wide-by-1/4-inch-deep-by-three-inch-long groove was routed on the underside of the starboard base to accept the aluminum upright. The regulator and solenoid assembly were mated together and bolted to the upright, and the upright was bolted to the base.
Four 1/4-inch holes were drilled through each base at opposite sides and through the deck. With the base in place, the hole in the deck for the gas line and control wire was carefully located and drilled for a watertight deck fitting. Sealer was added to the bottom of each base and four, 3-inch-long 1/4 20 eye bolts were bolted through the bases and stern deck. The tank bases were firmly in place with the regulator and solenoid assembly close to the tank.
Four lengths of 3/8-inch shock cord were made up and stretched from eye bolt to eye bolt across the top of each tank. Another 3/8-inch shock cord held the regulator and solenoid assembly against the tank, making the tank and regulator assembly one secure unit. The gas line and solenoid control wires were fed through the watertight deck fitting and back to the stove and gas solenoid control gas switch in the galley. The spare tank sits on the base and is held down with 3/8-inch shock cord; no regulator or controls are used with the spare tank. Changing tanks takes about two minutes.
A little later I was bemoaning the ugly appearance of the tanks during a visit from our friend and canvas maker Diane Beck on Ariel III. Immediately, Diane made some measurements and went back to her boat and made waterproof Weblon covers for each tank. The active tank cover has a clear plastic window to observe the gas pressure gauge. The white lumps on our stern are identifiable to a passer-by as propane tanks if you look closely. This solution worked better for us than the propane tank locker alternative. The propane project turned out better than expected; it worked flawlessly, and didn't interfere with boat operation for 4,200 nm from Maine down the ICW, around to the Bahamas, Bermuda, and back to Maine. We went through several big seas and windy, squally weather; the tanks were rained on and repeatedly splashed with sea water, but the covers protected them from the elements and the shock cord held them securely in place. The latest inspection shows no problems. Not including our labor, the entire project cost about $1,200, including the stove, two aluminum tanks, regulator, hose, fittings, gas solenoid switch, wire, hardware, and custom-made tank bases and covers.