How long to leave gas turned on for ?

[W+T]

1 minute ago, Theo said:

How do you know that it was nowhere near dangerous?  I would have thought that the only indication of the fact that a gas leak was becoming dangerous was the loud bang and little bits of boat and occupants liberally distributed over the surrounding area.

 

N

good point, if the bilges had the correct mix etc etc

[StephenA]

36 minutes ago, Theo said:

How do you know that it was nowhere near dangerous?  I would have thought that the only indication of the fact that a gas leak was becoming dangerous was the loud bang and little bits of boat and occupants liberally distributed over the surrounding area.

 

N

Gas detector didn't bleep - and we knew it worked.

There's a very good reason why they add mercaptan to bottled LPG - it stinks at about 0.4 parts per billion ( Propane becomes combustible at a 2% concentration in air ) 

 

[Machpoint005]

23 hours ago, W+T said:

do you check for leaks on return to the boat or have a sensor to tell you there is a leak when on and off the boat ?

That's why bottled (and mains) gas is odourised.

Edited August 24, 2017 by Machpoint005
Sorry - didn't see StephenA's post above

[W+T]

30 minutes ago, Machpoint005 said:

That's why bottled (and mains) gas is odourised.

No good when you are igniting an LPG heater by remote though. 

[Bargebuilder]

Why not turn the gas on remotely by sms, just before turning on the heater by sms? That way there would be no possibility of a gas accumulation within the boat when the heater springs into life and so no possibility of a gas explosion.

It would be very easy to also fit a gas alarm that sends you an sms from the boat should there be a gas escape. The same alarm could also cut off the gas supply by operating a solenoid within the gas locker.

All the equipment is readily and cheaply available from eBay if you do a bit of research.

 

[Theo]

20 hours ago, Bargebuilder said:

Why not turn the gas on remotely by sms, just before turning on the heater by sms? That way there would be no possibility of a gas accumulation within the boat when the heater springs into life and so no possibility of a gas explosion.

It would be very easy to also fit a gas alarm that sends you an sms from the boat should there be a gas escape. The same alarm could also cut off the gas supply by operating a solenoid within the gas locker.

All the equipment is readily and cheaply available from eBay if you do a bit of research.

 

All this technology seems a bit OTT to me.  When I arrive on the boat during a cold spell I find that by the time I have got things sorted the log burcher is well alight and the Mikuni is busy heating up the tank.  I don't have to leave my coat on for very long before the boat is at a civilised temperature.

When leaving the boat overnight we always turn off the gas at the bottles.

 

N

[Bargebuilder]

That is what I would do too, but if Wayne fancies automating his boat then why not?

[Theo]

1 hour ago, Bargebuilder said:

That is what I would do too, but if Wayne fancies automating his boat then why not?

Yes, indeed!

N

[W+T]

what my thought was in why are folk so unsure of there gas system to get leaks on it in a week or so, well even months.

 

And to have automated is cool i dont modern stuff but this means i can get to the boat and its toasty already afetr a along drive to it and for when i have friends wanting to use it it is a nice welcome fo them. 

 

 

[MtB]

On 23/08/2017 at 19:12, W+T said:

How long would you leave the gas turned on for at the cylinder/gas valve if you have a SMS LPG sensor ?

 

Same as if you didn't have one.

 

On 23/08/2017 at 19:12, W+T said:

Why that long or even not?

 

Because you won't know if it works (on the day you have the leak).

On 23/08/2017 at 20:03, StephenA said:

 

The ONLY significant gas leak we have had on Mintball in 30 years was caused by a BS examiner not fastening up the bubble tester point after completing the bubble test.... and we smelt that well before it got anywhere near dangerous.

 

Eh???

The whole point of a bubble tester is there is no unfastening of anything to carry out the test. Just a button to press and a window to look through, for bubbles.

[WotEver]

9 hours ago, Mike the Boilerman said:

Eh???

The whole point of a bubble tester is there is no unfastening of anything to carry out the test. Just a button to press and a window to look through, for bubbles.

We think he meant manometer test point. 

[blackrose]

On 23/08/2017 at 19:42, W+T said:

do you check for leaks on return to the boat or have a sensor to tell you there is a leak when on and off the boat ?

I don't really think gas sensors/alarms are designed to tell you if there is a gas leak, but rather to warn you about the presence of gas in the air - a subtle but important difference. They should be used as a last line of defence. Likewise a CO detector doesn't tell you much about the source of the CO, just that it is present in detectable proportions in the air.

As a DIYer, if you've just installed the gas system you should check every joint with gas leak detector spray and if you then want to regularly test the system for leaks fit a bubble tester in the gas locker - preferably at the same time you install the system rather than retrofitting it!

If one is not confident enough in the soundness of a gas installation to leave it on when not in use then I'd say it probably shouldn't be switched on at all. I live aboard and turn my gas off in the locker only when leaving the boat for extended periods, weekends, holidays away from the boat, etc. There's probably no real logic to that, just my habit.

Edited August 26, 2017 by blackrose

[Bargebuilder]

30 minutes ago, blackrose said:

Likewise a CO detector doesn't tell you much about the source of the CO, just that it is present in detectable proportions in the air.

It doesn't even tell you why it is sounding it's alarm!

Mine regularly goes off and shows how many parts per million of CO is present when there is no CO present at all, just because the solar panels are causing the batteries to gas and hydrogen is being released.

[Bargebuilder]

10 hours ago, W+T said:

And to have automated is cool i dont modern stuff but this means i can get to the boat and its toasty already afetr a along drive to it and for when i have friends wanting to use it it is a nice welcome fo them.

It is cool, and I hope you tell us how you get on.

If you can, have a single copper gas pipe to your Propex, with a joint at the heater and all other connections, bubble detectors, test points etc within the gas locker.

Treat all other gas appliances the same way.

As others have said, test all joints carefully, and periodically operate the bubble detector.

There are small risks in everything, but if you are meticulous in your work and test everything regularly then go for it!

 

[W+T]

Morning guys.

 

I started this thread as i was just wondering how some folk go on and there difference in choice. When i was askign about the SMS set up some folk found it hocking to have the LPG turned on while away from the boat incase there is a leak. Now a lot of folk dont even have a LPG sensor or anything of the likes. Which to me is a bit shocking nowadays.

Even being on board for a day or weeks you can get a leak and not always smell it. It can build up in the bilges and be ignited, small chance or not, it is still there. So there is little difference to me if you are on board or not but that you blow up yourself aswell if your on the boat.  

 

My set up i have no concerns about, if i need to do a job and have any concern at all it i would get a person capable of the job, maybe even qualified. This has yet to happen in anything i do. I have fixed brakes on many a car, not as a alight hearted thing as you would think. Easy job but needs doing to a good standard, you would not believe the things i have had to put right for folks that have tried to do there own. bloody scary.

My LPG system that i have not long finished has a bubble tester in the locker then to a three way valve/taps for oven/Malaga 5E water heater/Propex HS2000.

I find that a good way as to be able to shut off each appliance separate and the other can keep working. As in when i leave the boat i can keep the Propex supply on for the Automated setup.

I understand that the LPG detectors do not alarm if there is a leak but they do sense LPG so therefore there is a leak in the system, well in my case the appliance cupboard as the supplies pipe work are in one length with no joints to the appliance. So a sensor will be in the bottom of the cupboard.

Now i know of the LPG shut of solenoids i will be fitting one in the gas locker before the bubble tester along with a leak detector.

 

So interesting replies as always

 Ok enough waffling i got a boat to fit out, nearly there now  bring on spring time 2018

[Bargebuilder]

Just taken from the website of a 'Pilot' gas detector retailer, 'Pilot' being a very widely used marine unit, the current draw for the dual sensor unit is as follows:

"Draws 172 milliamps on standby, 484 milliamps with the valve open."        (Assuming you run at 12v)

Your gas cut-off solenoid valve will of course be left open if the gas alarm is left powered up, so the drain on your battery will be a constant  1/2 amp, so 12 amp hours every day.

Your battery bank shouldn't be run down to below 50% of its fully charged capacity to preserve it's life, so assuming your battery is used for nothing else, if you leave your boat for 14 days without some form of charging system, the minimum size of battery bank that you will need is 336 amp hours (three bigish batteries), and after the two weeks there will be nothing left for powering anything else on the boat, not even to start up the Propex.

You will either need a sizeable battery bank, shore power or solar panels.

This might be part of the reason that such detectors are less than popular with 'off grid' boaters, together with the reliability of the sensor heads and the cost of the unit and the inevitable spare parts.

 

 

[W+T]

47 minutes ago, Bargebuilder said:

Just taken from the website of a 'Pilot' gas detector retailer, 'Pilot' being a very widely used marine unit, the current draw for the dual sensor unit is as follows:

"Draws 172 milliamps on standby, 484 milliamps with the valve open."        (Assuming you run at 12v)

Your gas cut-off solenoid valve will of course be left open if the gas alarm is left powered up, so the drain on your battery will be a constant  1/2 amp, so 12 amp hours every day.

Your battery bank shouldn't be run down to below 50% of its fully charged capacity to preserve it's life, so assuming your battery is used for nothing else, if you leave your boat for 14 days without some form of charging system, the minimum size of battery bank that you will need is 336 amp hours (three bigish batteries), and after the two weeks there will be nothing left for powering anything else on the boat, not even to start up the Propex.

You will either need a sizeable battery bank, shore power or solar panels.

This might be part of the reason that such detectors are less than popular with 'off grid' boaters, together with the reliability of the sensor heads and the cost of the unit and the inevitable spare parts.

 

 

Bit much of a drain that then. I will likely have a small solar panel though. Batteries will be two 110amp.

 

I have been looking at these but still a 150ma drain i think. 

http://www.ebay.co.uk/itm/MQ-2-MQ2-Gas-Sensor-Module-For-LPG-Propane-Hydrogen-Arduino-Raspberry-Pi/161942495151?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649

The  to add this to the set up if i can work that out.

http://www.ebay.co.uk/itm/LPG-SOLENOID-SHUT-OFF-VALVE-WITH-LIQUID-PHASE-GAS-FILTER-8-mm/162624593394?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649

 

 

 

[Bargebuilder]

The gas solenoid is a bit short on detail.

Is the solenoid valve 12v dc?

Is it 'normally closed' with a current needed to keep it open so it fails safe?

How much current does it need to hold the solenoid open?

Electrics I understand but electronics no, so you are on your own with Raspberry Pi.

[StephenA]

On 26/08/2017 at 08:21, WotEver said:

We think he meant manometer test point. 

Yes which I confirmed at 22:15 on Wednesday