Propane Sniffer Meltdown
 

Hi, my name is Ari, and I own a 1978 Catalina 30. Long time reader,
first time poster.

I installed a vented propane locker with solenoid control switch and
sniffer in the bilge. I've had the boat hauled and various SF Bay-area
boatyard gurus have looked at the install and given it the "thumbs-up."

On Saturday, as we were motoring home into the marina to dock, one of
our passengers smelled smoke. My GF went below but didn't see or smell
anything.

As we were already about to turn up the finger towards our berth, we
proceeded to dock. As our guests began to gather up belongings and
climb off the boat, the acrid stench of burning plactic became
unmistakeable!

I killed the engine, went below, and quickly found that the bilge was
the source of the smoke. I removed the bilge cover board and was
surprised to see the (fairly shallow) bilge filled to within an inch of
the top. The propane sniffer was melted, and the wires leading to it
had melted through their casing and were glowing orange. A quick
glance at the control panel above the nav desk told me that the
automatic bilge pump had been left in the "off" rather than "auto
position." Arrgh! (I suspect guests using sinks in the galley & head
caused the bilge to fill with grey water -- the boat is certainly not
leaking now.)

I disconnected the positive leads to the house batteries and stood
ready with a fire extinguisher while my GF pumped the bilge dry with
the manual gusher.

The propane sniffer smoldered a bit but didn't ignite. We checked all
wiring as thoroughly as possible, but didn't notice any other signs of
damage.

A dramatic end to an otherwise beautiful day on the SF Bay!!!

I had a couple of follow up questions for the group:

- Should I move the propane sniffer out of the bilge to a spot under
the stove/above the cabin sole?

- As per the manufacturers instructions, the sniffer was wired
"always-on" to the battery terminals. Should I instead wire it through
the master switch so it can be turned off more easily in an emergency?

- How likely is it that wiring other than between battery/solenoid
control panel/sniffer could have been damaged?

- (Rhetorical) What the #&%$*( $#^@& good is a "safety device" that
causes fires?!?!?!? (OK, got that off my chest.)

Thanks,

- Ari

Ari

Glad to hear all ended well.

My advice would be to get it out of the bilge. These things do no
tlike getting wet.

On my boat, the sniffer is just above the cabin sole in the face of one
fo the settees. It is wired to bypass the master switch but is not
always on. It has its own switch right next to the master switch.
Procedure is to turn on the sniffer first. It will beep while it warms
up (10 - 20 seconds) and then go silent once its warmed up and no gas
is detected. I like this setup as it tests the sniffer every time you
get on the boat. I spent the first season with this boat diligently
turning on the sniffer and being happy at "silence" every time. Next
spring I found out that the sniffer had been disconnected the whole
previous season.

Matt

aroostifer wrote:

Hi, my name is Ari, and I own a 1978 Catalina 30. Long time reader,
first time poster.

I installed a vented propane locker with solenoid control switch and
sniffer in the bilge. I've had the boat hauled and various SF Bay-area
boatyard gurus have looked at the install and given it the "thumbs-up."

On Saturday, as we were motoring home into the marina to dock, one of
our passengers smelled smoke. My GF went below but didn't see or smell
anything.

As we were already about to turn up the finger towards our berth, we
proceeded to dock. As our guests began to gather up belongings and
climb off the boat, the acrid stench of burning plactic became
unmistakeable!

I killed the engine, went below, and quickly found that the bilge was
the source of the smoke. I removed the bilge cover board and was
surprised to see the (fairly shallow) bilge filled to within an inch of
the top. The propane sniffer was melted, and the wires leading to it
had melted through their casing and were glowing orange. A quick
glance at the control panel above the nav desk told me that the
automatic bilge pump had been left in the "off" rather than "auto
position." Arrgh! (I suspect guests using sinks in the galley & head
caused the bilge to fill with grey water -- the boat is certainly not
leaking now.)

I disconnected the positive leads to the house batteries and stood
ready with a fire extinguisher while my GF pumped the bilge dry with
the manual gusher.

The propane sniffer smoldered a bit but didn't ignite. We checked all
wiring as thoroughly as possible, but didn't notice any other signs of
damage.

A dramatic end to an otherwise beautiful day on the SF Bay!!!

I had a couple of follow up questions for the group:

- Should I move the propane sniffer out of the bilge to a spot under
the stove/above the cabin sole?

- As per the manufacturers instructions, the sniffer was wired
"always-on" to the battery terminals. Should I instead wire it through
the master switch so it can be turned off more easily in an emergency?

- How likely is it that wiring other than between battery/solenoid
control panel/sniffer could have been damaged?

- (Rhetorical) What the #&%$*( $#^@& good is a "safety device" that
causes fires?!?!?!? (OK, got that off my chest.)

Thanks,

- Ari



No fuse?

Nope. As per manufacturers instructions the sniffer was wired directly
to the batteries. I guess I could put a fuse (10A, 15A?) in there, but
then I guess if/when fuse goes the sniffer will silently stop working.
Unless I wire up a separate on/off switch as per Matt's suggestion and
verified I get a "test beep" when sniffer powers on.

I'm thinking the next boat may have a kerosene stove...

- Ari

Marley wrote in
:

No fuse?



Of course not! Boat installations of small-wired electronics is hardly
ever fused at a safe level for the size of the wiring involved. It's wired
to that 15 or 20A cheap thermal breaker that also drives the cabin lights,
those tiny wires to the compass light, #22 wire to the GPS and those #22
wires to those GOD AWFUL little plastic Hella fans with NO INTAKE GUARDS in
the cabin!

You want us to put in a LITTLE FUSE PANEL to protect all those little
wires?! What a concept!

I'm confused about the remarks of the STUPID bilge pump switch. The bilge
was full of water or smoke from the burning wiring?? Or did the stupidity
of the bilge pump actually having an OFF position submerge this gas sensor,
causing it to short out?? The CORRECT wiring procedure for the bilge
pumps, ALL the bilge pumps, is a separate circuit STRAIGHT to the battery
banks for each bilge pump. + battery with fuse within 6" of battery
terminal (inline ok) to float switch to bilge pump to - battery terminal.
If you so desire, the float switch may have a manual override switch in
parallel with it in case it gets clogged or disabled, a good use for this
stupid bilge pump switch. The fuse rating of EACH bilge pump would be
protecting the SMALLEST wires, those little damned things to the plastic
floatswitch or pump motor, in the circuit. I like to run the bilge pump
under a load (pumping water unobstructed) while I measure its current. If
it draws 1.3A under load, I want the next-higher-size fuse of twice that
current ONLY IF THE WIRES CAN HANDLE IT. If the bilge pump motor becomes
stalled with trash, I want the fuse to blow....instead of the bilge pump
motor to just sit stalled and fry, possibly melting or catching fire. The
bilge pump draws a lot of current starting under load, so use slow-blow
fuses to prevent nuisance blows, rendering it useless. I find a STALLED
Rule pump draws plenty more current to blow a double-the-normal-current
fuse to save the pump. If it shorts, the fuse blows. If it stalls, the
fuse blows saving the pump for a cleanout. No fire, no smoke...safe.
Because EACH bilge pump has its OWN circuit/floatswitch/fuse, blowing one
fuse doesn't disable all the pumps at once. Life goes on.

There is the neatest little piezoelectric nag alarm at Radio Shack. It's a
round, black plastic, 12V, nauseatingly antagonizing, pulsating beeper
noise maker. Mount it through the plastic somewhere in the cockpit that
will aggravate any sleepers below, plus anyone walking by on the dock.
Connect this alarm (ours also has a bright red pilot light in parallel with
it with a little sign saying what it means)....Connect this alarm/light
combo ACROSS the fuse! + side of the beeper to the battery side of the
fuse....- side of the beeper to the floatswitch side of the fuse. It will
not beep or light UNTIL THE FUSE BLOWS, alarming you that that something is
wrong with THAT bilge pump. Compared to a sunken ketch, cost of this
little beeper alarm is MINIMAL!

There...now NOONE can turn off the bilge pumps unless they unplug the fuse
manually. The fuse protect the circuit from losing its "magic smoke" which
makes all electrical/electronic gadgets run. It even protects the bilge
pump from the trash that got in and locked the pump up so it won't fry the
pump motor! When the trash...or a short....or a bad (shorted only) motor
blows the fuse, the alarm sounds that something is wrong with THIS bilge
pump, making troubleshooting at our earliest possible moment
happen...before the water comes up over the teak and holly. Much better!

Add another float switch on another separate, straight-to-battery-like-the-
bilge-pump circuit. This float switch is 6" higher than the one that turns
on the pump and should NEVER activate. If it does, it powers a Radio Shack
alarm system 130db reentrant horn alarm that looks like a PA speaker up on
the mast pointed down the dock so NOONE SLEEPS AS YOUR BOAT SINKS! As it
has no OFF switch, they'll have to call you IMMEDIATELY to shut the damned
thing up before the boat sinks.....(c;

Flooding in the bilge is never funny!

Please REWIRE every small electrical and electronic load in this boat in as
many separate little fuse panels as is necessary so that each small load
has its OWN properly-fused circuit. Hook the fuse panels to the breaker
panel in the boat with wire appropriate to the size of the breaker. 20A
breaker, use #12 or #10. 15A breaker, use #12 or #14....no smaller.
Glowing wires like you've already witnessed can burn that plastic/epoxy
beauty right to the waterline!

propane is heaver than air so if are concerned about propane in the bilge I
think that's where you should have the sniffer located.
"Larry W4CSC" wrote in message
...
Marley wrote in
:

No fuse?



Of course not! Boat installations of small-wired electronics is hardly
ever fused at a safe level for the size of the wiring involved. It's
wired
to that 15 or 20A cheap thermal breaker that also drives the cabin lights,
those tiny wires to the compass light, #22 wire to the GPS and those #22
wires to those GOD AWFUL little plastic Hella fans with NO INTAKE GUARDS
in
the cabin!

You want us to put in a LITTLE FUSE PANEL to protect all those little
wires?! What a concept!

I'm confused about the remarks of the STUPID bilge pump switch. The bilge
was full of water or smoke from the burning wiring?? Or did the stupidity
of the bilge pump actually having an OFF position submerge this gas
sensor,
causing it to short out?? The CORRECT wiring procedure for the bilge
pumps, ALL the bilge pumps, is a separate circuit STRAIGHT to the battery
banks for each bilge pump. + battery with fuse within 6" of battery
terminal (inline ok) to float switch to bilge pump to - battery terminal.
If you so desire, the float switch may have a manual override switch in
parallel with it in case it gets clogged or disabled, a good use for this
stupid bilge pump switch. The fuse rating of EACH bilge pump would be
protecting the SMALLEST wires, those little damned things to the plastic
floatswitch or pump motor, in the circuit. I like to run the bilge pump
under a load (pumping water unobstructed) while I measure its current. If
it draws 1.3A under load, I want the next-higher-size fuse of twice that
current ONLY IF THE WIRES CAN HANDLE IT. If the bilge pump motor becomes
stalled with trash, I want the fuse to blow....instead of the bilge pump
motor to just sit stalled and fry, possibly melting or catching fire. The
bilge pump draws a lot of current starting under load, so use slow-blow
fuses to prevent nuisance blows, rendering it useless. I find a STALLED
Rule pump draws plenty more current to blow a double-the-normal-current
fuse to save the pump. If it shorts, the fuse blows. If it stalls, the
fuse blows saving the pump for a cleanout. No fire, no smoke...safe.
Because EACH bilge pump has its OWN circuit/floatswitch/fuse, blowing one
fuse doesn't disable all the pumps at once. Life goes on.

There is the neatest little piezoelectric nag alarm at Radio Shack. It's
a
round, black plastic, 12V, nauseatingly antagonizing, pulsating beeper
noise maker. Mount it through the plastic somewhere in the cockpit that
will aggravate any sleepers below, plus anyone walking by on the dock.
Connect this alarm (ours also has a bright red pilot light in parallel
with
it with a little sign saying what it means)....Connect this alarm/light
combo ACROSS the fuse! + side of the beeper to the battery side of the
fuse....- side of the beeper to the floatswitch side of the fuse. It will
not beep or light UNTIL THE FUSE BLOWS, alarming you that that something
is
wrong with THAT bilge pump. Compared to a sunken ketch, cost of this
little beeper alarm is MINIMAL!

There...now NOONE can turn off the bilge pumps unless they unplug the fuse
manually. The fuse protect the circuit from losing its "magic smoke"
which
makes all electrical/electronic gadgets run. It even protects the bilge
pump from the trash that got in and locked the pump up so it won't fry the
pump motor! When the trash...or a short....or a bad (shorted only) motor
blows the fuse, the alarm sounds that something is wrong with THIS bilge
pump, making troubleshooting at our earliest possible moment
happen...before the water comes up over the teak and holly. Much better!

Add another float switch on another separate,
straight-to-battery-like-the-
bilge-pump circuit. This float switch is 6" higher than the one that
turns
on the pump and should NEVER activate. If it does, it powers a Radio
Shack
alarm system 130db reentrant horn alarm that looks like a PA speaker up on
the mast pointed down the dock so NOONE SLEEPS AS YOUR BOAT SINKS! As it
has no OFF switch, they'll have to call you IMMEDIATELY to shut the damned
thing up before the boat sinks.....(c;

Flooding in the bilge is never funny!

Please REWIRE every small electrical and electronic load in this boat in
as
many separate little fuse panels as is necessary so that each small load
has its OWN properly-fused circuit. Hook the fuse panels to the breaker
panel in the boat with wire appropriate to the size of the breaker. 20A
breaker, use #12 or #10. 15A breaker, use #12 or #14....no smaller.
Glowing wires like you've already witnessed can burn that plastic/epoxy
beauty right to the waterline!

Larry W4CSC wrote:

I'm confused about the remarks of the STUPID bilge pump switch.
snip
Or did the stupidity
of the bilge pump actually having an OFF position submerge this gas sensor,
causing it to short out??

Correct. The bilge pump switch made by Rule has 3 positions:
ON/OFF/AUTO. The bilge pump switch panel does in fact have a fuse, but
the propane sniffer doesn't, err, didn't.

- Ari

On 6 Jun 2005 14:29:22 -0700, "aroostifer"
wrote:

Nope. As per manufacturers instructions the sniffer was wired directly
to the batteries. I guess I could put a fuse (10A, 15A?) in there, but
then I guess if/when fuse goes the sniffer will silently stop working.
Unless I wire up a separate on/off switch as per Matt's suggestion and
verified I get a "test beep" when sniffer powers on.

I'm thinking the next boat may have a kerosene stove...

- Ari


Pewople have mentioned placing an incandescent lamp acroos the fuse as
a tell-tale.

You could use a LED reistor combination as easily as a lamp, if you
can check polarity is correct, or even a flashing led which is the
most e-yecatching approach, I'd think.

Brian Whatcott Alkus OK

"aroostifer" wrote in
oups.com:

doesn't, err, didn't.


Bingo! Glad you're now surveying all the OTHER equipment in the boat, too,
to see what ELSE is fused way above its capability to cope with such
shorts.

It's just an amazing thing more boats don't catch fire....breaker panel
cabinetry made out of WOOD or some flammable plastic. Yecch! It's all
made so CHEAP, DAMMIT!...

You think boats are bad, you should look at small aircraft. At least
in a boat you can change out the components. In an aircraft, the FAA
makes you keep the original sub-Radio Shack quality components because
they are "Original". Jeezzy cripes, at least in a boat you are
sitting in a big fire extinguisher. In an airplane, the fire exits
have a very tall first step.

I find it amusing, after obsessing about keeping water out of boat
wiring, to walk out to my plane and go by ones where you look in the
cowl and, right there in front, exposed to the full 150 mph blast
while flying through the rain, is the ALTERNATOR! Yup, an auto /
aircraft alternator (much more expensive but also poorer quality than
a marine unit) will function with a fire hose turned full on it.

--

Roger Long



"Larry W4CSC" wrote in message
...
"aroostifer" wrote in
oups.com:

doesn't, err, didn't.


Bingo! Glad you're now surveying all the OTHER equipment in the
boat, too,
to see what ELSE is fused way above its capability to cope with such
shorts.

It's just an amazing thing more boats don't catch fire....breaker
panel
cabinetry made out of WOOD or some flammable plastic. Yecch! It's
all
made so CHEAP, DAMMIT!...