Gas lockers
Gas lockers
This perennially thorny topic has raised its head again on the Discussion Board. There seems to be unanimity about the question which is:
Where to site gas bottles on a Twister so that the gas installation meets the regulations and is reasonably aesthetic?
There seem to be three main solutions, all of which are discussed below and all of which have drawbacks. These are:
1) In an exposed position on the aft deck - definitely safe but of questionable aesthetics and tricky if you have self steering gear
2) In a locker constructed in the lazarette or in the aft locker at the back of the cockpit - a workable solution but requires quite a lot of construction effort
3) In a cockpit locker - this solution can obviously be made to work as I suspect it is the one most Twisters currently have. Perhaps whether you get a lot of water coming in it depends on whether you sail heeled over a lot - maybe you should be reefing earlier!
Here are the (slightly edited) discussions direct from the web site, followed by a reproduction of an article by Stuart Cooper on his solution to the problem on Killaloe, previously published in the Dec 1999 magazine
From David Holyoake KERYLOS
Hi, I'm both a new Twister owner and a new association member. So, if my questions have been dealt with many times before, I apologise! 'Kerylos' has what I assume is the original type gas locker - port side in the cockpit and draining into the same - not good news according to everything I've read! Looking at a few back issues of the Twister magazine that came with the boat, it seems that the favoured way to improve on this is to make and fit a completely new locker in the aft lazarette. However, I just wondered if anyone has improved on and made safe the existing arrangement? Perhaps it is possible to block up the existing drain, redrill, and plumb in (using large diameter crush and gas proof pipe)a new drain. This could exit the locker at the back bottom corner, be neatly clipped and run along the side of the hull and slightly down, and then exit out through the transom. Has anybody tried this method? Do you think it is practical and could work? Any advice or alternative ideas would be welcomed. If at all possible I would like to see if the existing locker could be made useable - My aft deck has a solar panel and Aries wind vane fitted to it, so, it's already a bit cluttered! Alternatively has anyone got an excellent 'Blakes' paraffin cooker for sale!!!
Reply from Geoff Doggett - CARRONADE
Hi David and welcome to Twistering! I've got 2 bottles mounted on the aft deck and have long thought about putting them in as you suggested. But, despite clutter on the aft deck (they tuck in quite well inside the pushpit sitting on semicircular wooden mounts which engage with the bottom of the bottle), I've concluded they are in the best place a) for safety (all gas leaks just blow or fall overboard) b)easy access and changing c)leaves more locker space. I've got an Alden bubble detector fitted in the lazarette and also a rotary safety switch in the galley.
From Anna Gawley, SINOPE
Hello. I am also a newish Twister owner and new association member (my best Christmas present!). I also have a gas design problem on my Twister 'Sinope'. She has the gas bottle in her starboardside locker in an open topped but otherwise sealed box. A tube from the bottom of the box drains escaped gas out through hole on the waterline in the middle of the transom. Unfortunately the drop is not great and the hole seems to let water in more often than it lets gas out and the gas bottle swims in a pool in the gas box. This problem is exacerbated when 'Sinope' is on a port tack. The gas box fill up even further and if the sea is rough the water jumps out into the bilges. It's most disconcerting to find yourself ankle deep in floating floorboards. I wouldn't recommend this solution! I note the suggestion of carrying the bottles externally. Any other ideas out there?
From George Davidson, ARRAN COMRADE
I still think that you will lose too much internal space if you place the bottles anywhere other than on the rear deck. I am having 2 stainless steel "cages" made to accommodate 2 gas bottles and will provide pictures when the work is completed.
I am also having a "bubblier" fitted in the lazarette and an "on/off" switch by the cooker.
From Ken Munn, INDIGO
Indigo drains gas from a sub-locker in the port cockpit locker, into the cockpit., which as the bottom of the cockpit drains are almost always underwater, is pretty useless. There is, however, a solenoid valve fitted immediately downstream of the bottle, and we turn the gas off by switching the solenoid off (control next to galley), and letting the flame die before closing the cooker tap.
I wondered about putting a top-loading but otherwise sealed locker in the 'stern' deck, but a tape measure seems to say that it won't work, not with standard sized bottles anyway.
Has anyone done this successfully?
From Philip Collcutt, SEA MISTE OF HAMBLE
David, Welcome to Twistering! We inherited an open topped gas locker to hold two medium sized Camping Gaz bottles in the starboard cockpit locker on Sea Miste which drained through the transom. It worked very well but during our refit last year we had a new closed locker built to meet somebody's standards as part of bringing the gas system up to somebody's regulatory requirements. Sure enough it floods through the drain, especially on the port tack. The yard have accepted the problem as warranty work and intend to raise the floor of the locker and move the drain exit as near the centreline as possible. There is plenty of headroom in the locker to do this and the requirement for a draining and a sealed locker seem reconcilable.
From John MacMullen, CRIONNA
Here's one I bet you haven't thought of.....
Had a 'phone call the other day from a member looking for info on poor autohelm performance. UK gas bottles are ferrous and, subject to proximity, may cause significant deviation to the autohelm's fluxgate compass. Possibly in extreme cases the rate of change of deviation may exceed the heading alteration so the fluxgate will be totally confused! A solution might be, before going firm on major modifications, to try moving a gas bottle around near the energised autohelm and see how close/far the sphere of influence is. Even then each bottle will be different. I have a gut feeling that you might be looking for a minimum 600mm 'safe distance'. Good luck
From David Nash, GREEN JACKET
When I bought Green Jacket last year I had to upgrade the gas locker to meet new regs. There was a glassed timber box that contained two calor bottles; the box drained through a short length of hose down to a draincock 15cm above the waterline. I removed the box and had a stainless steel one fabricated that houses two large camping gas bottles. The removable steel top covers only the front bottle, and the reduced size of bottles means the box is shallower than the previous one and therefore its base is higher above the water line. It still drains in the same way, which does mean that on port tack its bottom fills with water - but only when the boat is well heeled - and I can always turn off the drain cock. This seems a satisfactory solution. I will provide a sketch if anyone wants one.
From Tristan Southall, CANTATA
We too have the gas locker in the starboard cockpit locker, draining into the cockpit itself.
As well as the main cockpit drains, with seacocks, draining below the waterline, we also have an additional aft cockpit drain, with no seacock, draining through the transom, above the waterline. This additional drain was installed so the boat could be left with the main cockpit drain seacock closed, without the cockpit filling up with rain water. When underway with even a slight following sea, water flows in through this aft drain, but immediately drains out of the main cockpit drains (which are always open underway). As we have a cockpit sole grid, this flow is pretty unnoticeable. We also have a bung for the aft drain to stop the flow if necessary when underway.
The consequence of all this from a gas perspective is that yes, gas drains into the cockpit, but it then drains immediately out through the transom, above the water line.
Hope this concept is not flawed in any way!
From Geoff Lodge , SEA CHEETAH
All solutions seem to have some disadvantage. Has anyone practical experience of Taylor's paraffin stoves. Are they a worthwhile alternative to gas?
From Johan de Smet, LITTLE TUK
No. I've got a Taylor stove and it is virtually impossible to preheat it with methylated spirits while at sea. In calm weather and in harbour it works fine when you follow the procedure. I will probably convert to gas this year.
From George Davidson, ARRAN COMRADE
My insurance company (St Margaret's) will not allow me to use my newly installed gas system until I have had it checked and signed off by a properly qualified "Corgi" registered engineer. Whilst that may sound quite reasonable, I am unable to find such a person in the whole of Scotland!
The problem seems to be that a special Marine Certificate is required which cost around £500 per annum. On top of that, a £2,000 Public Liability annual insurance premium is required. That explains why there is no person in Scotland (at least in the West) has the qualification.
My installation consists of the gas bottle on the rear deck, a nearby "bubblier", another switch in the cabin and a cooker with fail-safe burners. What more can one do?
PS I forgot to mention that I also have a gas alarm installed!
FOOTNOTE
Having explained the dearth of properly registered Corgi engineers, my insurance company has accepted my gas installation.