Gas Alarms

[jamesa]

Concluded that I really should get one. Any recomendations? Also any suggestions about siting and wiring (I presume they should be always on rather than relying on someone to switch it on?).

BTW - boat is a 34ft cruiser/racer & the only gas appliance is a cooker situated next to the main hatch, fed from a gas locker in the cockpit

<hr width=100% size=1>

 

[StephenW]

I had the same dilemma and finally opted to wire it into the same circuit as the water pump. It's one of the first things we switch on and generally remains on whilst aboard. However it does allow you to switch it off, which you may want to do when away from the boat as it will not be possible to do anything about it anyway even if it does alarm.

<hr width=100% size=1>

 

[webcraft]

Main problem is where to site it.

Most are under the cooker, as low down as possible.

Gas, however, collects at the lowest point i.e. the bilges. In a deep bilged boat like mine this can be a lot of gas. However, a gas alarm in the bilges may/will be triggered and/or ruined by water sooner rather than later.

I'm thinking of getting a portable gas alarm on a string for dangling in the bilge when returning to the boat or when particularly paranoid, in addition to the fixed one under the cooker.

- Nick

<hr width=100% size=1><font size=1><A target="_blank" HREF=http://www.bluemoment.com>http://www.bluemoment.com</A></font size=1>

 

[StephenW]

PS Compass do one for about £45 - combined sensor and alarm - I put mine at skirting/floor level below cooker

<hr width=100% size=1>

 

[jerryat]

Hi!

I fitted a unit called (or made by) Canary!! The logical place to fit the sensor is in the bilge as near to the cooker as possible, which on my boat was also close to the deepest part of the bilge. We never have any water in the bilge, but nonetheless, decided to screw the sensor to the UNDERSIDE if the floor panels just in case we ever did!!
And the bilge is where gases etc collect being heavier than air.

I strongly recommend wiring it to it's own circuit breaker/switchfuse and leaving it permanently on. The battery consumption is barely measureable so there's no risk of a flat battery, and someone else may here the alarm if you are not on board and a problem arises. I've twice been in the position of contacting an owner to tell him his alarm was going! I fitted the alarm unit itself in the galley area where the alarm could be heard from the cockit as well, though that is a matter of personal preference/necessity.

Make SURE you get a sensor that is adjustable for sensitivity, otherwise you will find it going off when you spill strong cleaners and the like - a real pain! I set mine to go off after a few seconds of holding a gas cigarette lighter (unlit of course) over the bilge and it's been perfect.

Hope this helps

Good sailing!



<hr width=100% size=1>

 

[AndCur]

I have just fitted a gas alarm to my boat. I chose the SF model with twin remote sensors. As I don't have a gas locker that drains
overboard (there's no room to build one) I have one sensor beside the cylinder and the other sensor inside in the below the cooker.
Hopefully I will never need it but it does give some piece of mind


<hr width=100% size=1>

 

[Fin]

Bought one about 3 weeks ago and went for the "Pilot" one. As gas detectors they are prob all the same but the Pilot has the lowest power drain from the ones I looked at. Details and power reqd for various models are on the calor marine shop website.

Fin

<hr width=100% size=1>

 

[SydneyTim]

Surely the whole point is for it to be on when you are away from the boat precisely so that if there's a leak and gas has pooled in the bilges, you don't turn the electrics on when you get on board as any spark at all and you're dead.

Wire it in the low point of the bilge on the same circuit as the bilge pump.

<hr width=100% size=1>

 

[cpedw]

If you want to keep it really simple, there is a kit from CPC, <A target="_blank" HREF=http://custom1.farnell.com/cpc/product.asp?catalog_name=cpc+catalogue&category_name=&product_id=260104>http://custom1.farnell.com/cpc/product.asp?catalog_name=cpc+catalogue&category_name=&product_id=260104</A> which does the job for less than a tenner.
It has adjustable sensitivity but I noticed this winter its sensitivity is temperature dependent.
I mounted the detector on an extension right below the cooker, with the rest of the circuit and a sounder further away. It comes on when the boat's master switch is turned on. The alarm always sounds for about 5 seconds immediately after switch-on.
I hope that helps.
Derek

<hr width=100% size=1>

 

[jamesa]

I always switch the gas off at the bottle when leaving the boat - bottle is in a drained gas locker so there should never be a leak inside the boat to go bang on my return.

Several people have mentioned potential problems with the sensor getting wet - is this really an issue? Most logical place for the sensor in my boat is the bilge area imediately below the cooker (it's all pretty shallow), but that one area that always accumulates water, if only from wet people/sails coming down the hatch

<hr width=100% size=1>

 

[jamesa]

The pilot is at the top of my list, both for power consumption, as you mention & also price. I'm also considering the Marinecare Dualwatch, as this also offers CO detection & flush mounts (which looks a bit smarter imo). Anyone had any experience of these?

<hr width=100% size=1>

 

[BigART]

I have a Pilot unit with the sensor mounted at the base of the cooker which is not far from the companionway. After about 2 years, the unit starting to sound continuously even with no gas on board and a good airing. I suspect that it got hit by a splash of water. The manual is very specific on this being a problem.

I was quite surprised by the power consumption of 80 milliamps. Over a two week holiday on board, this is not trivial. I certainly wouldn't leave it permanently connected.

<hr width=100% size=1>I could well be wrong, if so I apologise - please correct me.

 

[findboats]

I have a commercial vessel and under the MCA code of practice you have to have an approved gas alarm.

I chose the Pilot ( http://www.technisolltd.co.uk/gas-alarms.html) gas alarm (very reasonably priced from http://www.asap-supplies.com/ and have been very hapy with it.

Current drain from the battery has not been an issue and I can honestly say that the support from http://www.technisolltd.co.uk/gas-alarms.html is excellent.

As for location, the lower the better.

As a rule, I turn off the gas at the bottle every time I leave the boat. This allows me to wire the gas alarm into the main battery switch for the electrics as any gas that may have leaked into the cabin will be minimal and not be cause for concern when switcxhing the battery power on.

hope this helps.

www.findboats.co.uk

<hr width=100% size=1>

 

[dulcibella]

My Pilot alarm sensor is in the bilge. This is a deep space in a long-keeler, so I'd have to be seriously sinking to get water near it. It seem to work very reliably from that position - a test puff of gas from a cooker lighter released in the bottom of the space set it off within 30 seconds.

<hr width=100% size=1>