When we ordered Dirona back in 2009, we specified a propane barbecue and stove top, along with four 20-gallon (9 kg) aluminum propane tanks. Three of those tanks are stored in the cockpit locker underneath the barbecue, with a fourth in the aft port cockpit locker. We specified so many because filling propane tanks outside North America can be a real hassle. Many counties use unique connectors that are incompatible with those used in North America and cannot fill foreign propane tanks.
A common solution for world-cruisers in this situation is to build an adapter between an in-country tank and their tanks, and gravity-fill the on-board tanks. This is both time-consuming and wasteful. Time consuming because you have to first build an adapter that takes the local tank fitting and adapts it to the US fitting. And, once that has been done, the propane can only be shifted between tanks by slight differences in pressure caused by temperatures differences. Wasteful because it’s impossible to get all the propane from the donor tank into the receiving tanks, so you end up only able to use a portion of what you bought.
Propane tanks throughout the world have their empty weight stamped on the tanks or included on a collar tag. So, with a luggage scale, we can weight tank and subtract the empty weight to get amount of propane in the tank. This gives a very precise data point on how much propane is left. We know we consume 1.9 lbs/month so this gives us a good read on how much time we have left.
Our approach of having lots of tanks has avoided the foreign refill issue so far. We consume on average 1.9 lbs (0.9 kg) of propane per month when in full live-aboard operation where we are cooking all meals. On this example, our original set of 4 tanks would last 42 months. We have also been lucky on our trip around the world and twice so far have found places outside of North America that can fill them, once in New Zealand where a kind tank operator decide to help us even though our tanks are not certified by his regional authority and technically shouldn’t be filled. The other time was in St. Lucia where they see many US boats and filling US propane tanks is a common request.
Since last departing the US in 2017 for Europe, we’ve not yet needed to fill the tanks, and we still have several weeks of propane left. But because we don’t plan to spend time in marinas and cities over the next couple of months, mostly due to the current COVID-19 recommendations, we really wanted to have a full load of propane on board. We needed to find a way to fill our tanks in the UK.
We were unable to find anyone to fill our tanks in the UK for a variety of reasons. First, the fittings used here are different so, unlike New Zealand, they don’t have the ability to fill them. We have hoses that could be used to adapt an existing supply to our tanks, but technicians are uncomfortable doing this since it would violate local jurisdictional requirements. And, perhaps more important, it’s getting increasing common all over the world, and in the UK, to use central tank filling and then do tank exchange. Actual tank filing stations are getting less common. Adding to the complexity of getting these tanks filled, they are now eleven years old and need to be certified before they can be refilled. Of course, we can’t get them to a US certifier and a UK certifier won’t certify foreign hardware.
Gravity-filling our existing tanks held little appeal, so we instead decided to replace the existing tanks entirely with locally-sourced tank-exchange ones. To make this work, we would need to obtain tanks that would fit in our locker and adapt our existing tank-to-boat propane pigtail hoses to the UK tanks.
Mechanical Services Ltd. in Portland, UK sourced the tanks and parts for us. Both were extremely helpful, as transporting large amounts of propane without a car is a challenge and obtaining the parts would have been difficult too. We cut off the boat-end fitting from our existing tank-to-boat propane pigtail hoses and then removed that same end from the UK propane pigtail. We then put the US propane fitting into the UK sourced propane pigtails and crimped the ferules to complete the hose. This gave us propane pigtail hoses that could attach to our US fitting house supply on one end and a UK propane tank on the other.
The first test was whether the new 6kg tanks would fit in our locker. We chose the tanks to be the largest tanks that would still fit in our enclosure so it’s no surprise that they fit but, still, it was a relief. Because these 6kg tanks are smaller than our original 20 lb (9 kg) tanks, we can fit all 4 in the cabinet and no longer need two propane storage areas.
We hooked everything up and tested the system. We have propane and there are no leaks. We tested for leaks in two ways. The first was using a leak detector spray that Andy of Mechanical Services Ltd. lent us so we could properly check for leaks. The second was to put the system on, fully pressurize it, then close the tank and watch for a half day with no appliances in use to detect leak-down.
The old tanks had holes drilled through them that secured them via bolts and thumbscrews. These bolts weren’t compatible with the new tanks, so we cut them off and instead installed ratchet-strap attachment points to secure the new tanks. This system will likely be an improvement over the old and more convenient.
Portland Marina was willing to recycle the old tanks, so we carted them up to their shoreside hazardous waste depot. It felt a little wasteful to discard four perfectly good tanks, but they’ve served us well and we likely wouldn’t use them again in the US. They were over eleven years-old and would need to be recertified at a minimum. And we’re planning to move to bottle-exchange programs rather than using fill stations.
It is awesome to have a full load of propane that will last 28 months at our 4 year average of 19 lbs/months. And, even better, we now have a solution where we can just swap out a tank in the UK. While we don’t carry as much propane as before with 53 lbs (24 kg) versus the 80 lbs (36kg) we used to carry, getting more now is a simple and inexpensive tank swap while we are in the UK. And should we need to fill in another country, we can apply the same approach of building a new pigtail and sourcing the tanks locally.