Our h36 has a factory-installed Sea Fire FG 50A extinguisher in the engine compartment. Noticed this Spring the gauge was reading well above full when cold and almost pegged beyond full when the engine compartment was warm. Replacement will be close to $300. Wondering if anyone has seen this problem and if it's okay to use as-is? Not familiar with the extinguisher content, but what could cause pressure to build in the bottle, or could the gauge be faulty?
Automatic Fire Extinguisher Issue
- Thread starter Dan_Y
- Start date
Call a fire extinguisher company and they will come to the boat, inspect all your extinguishers and charge those that are not functional. We should all be doing this every year, but in this age of throw away rather than maintain, I'm afraid too many of us just go to Wally'sWorld and buy cheap replacements to keep the coasties happy.
I also have a SeaFire system in the engine compartment. One day I couldn't start the engine and everything appeared fine. Was only by accident I realized that the tank was empty. I could run the engine by using the override switch or by putting a jumper wire between the contacts of the connector. The tank was in perfect condition and the little glass valve was intact. I was going to pass thru Baltimore coincidently so I stopped at their location and was able to exchange the tank for a new one for $165+/- without shipping. Got it home and installed the new tank and within a week it also was empty. I had to ship it back and they sent me a new one that seems to be working. I don't know about the quality of the system but all the people at SeaFire were very nice and helpful.
No sure what the agent is in the tank but supposedly it leaves no residue. After my tanks both emptied there was none.
Oh yeah, likely a halon replacement like Halotron. Surprised FireGas allow for an engine bay install, too hot in there for this stuff. Typically you remote mount the tank in a halon system. That may be your problem with false triggers.
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Halon is an ODS and a terrible greenhouse gas. The world banned its manufacture. FM200 is still a bad greenhouse gas but not an ODS. It is much heavier than halon. As for why the pressure went up with temperature PV=nRT. In a closed system V, n, and R are constants. So pressure is directly proportional to temperature. FM200 may not be an ideal gas but the idea applies. Just ask Roger Goodell.
I think Brady and Belicheck (sp?) have a better understanding of EVERYTHING than does Goodell. That includes the behavior of an ideal (or semi-ideal) gas, the power of money, and the ineffectual use of hot air.
Thanks Uncle Dom. Dave, the pv=nrt is precisely what's odd. When we bought the boat last August, during the survey I noticed the extinguisher was indicating a needle width above full. Right now, in the same temperature, the indicator is about 3-4 needle widths above full, and as expected, increases even further after running the engine. T increases so P follows. In this case, unless the gauge is bad, either V decreased or n increased. that is what puzzles me. so since that is essentially impossible, I'll go with a failing gauge. SeaFire offered no explanation other than is best to replace it. Thanks. Dan
Is it possible that someone is sneaking onto your boat and filling up your extinguisher to mess with you? I worked with some guys that did that to a fellow worker during the 1979 gas crisis. They were pouring gas in his car at lunch and he was bragging about getting 50 miles to a gallon. When they stopped he took the car in to get it fixed.
Haha...wish those guys wound sneak in one night and wax the boat and put on new sails...just sayin...