CO Mystery???

[steve wardwell]

I've had the experience and posted it on the BNO forum under the heading "just a tidbit of info".....It's my belief that Hydrogen can be seen by CO detectors. Our inverter has a desulfating mode once a month and this will set off the CO.

[junkman42]

My co detector alarms when battery bank is in equalize charge and sounded when My bank went into meltdown due to a shorted battery.  I am of the opinion it is not hydrogen but acid fumes, could be wrong but perhaps only the Shadow knows!  John L

[gumpy]

In the half hour since I took the units out this morning and closed up the bus, the CO level went to 77 as measured by the new battery unit.  Both it and the 12V unit were sounding an alarm.  The old unit reported zero (am sure it is dead).

Jim,

Consider doing another test where you unplug your batteries for a day (if possible), vent the coach, and then redo the test with the detectors. If you get nothing, then plug in the battery charger and see what happens. Since you have two detectors that you know will trip, it would be good to know what's tripping them and maybe by isolating each possible thing you can find out and report
back to us. I was not able to conclusively determine that it was my batteries, but it was very coincidental.

craig

[rv_safetyman]

First of all, I have fixed the link in one of my posts.  Turns out that, as someone pointed out, I was putting a period at the end of what looked like a sentence, but it got included in the hyperlink.

I have run out of time to play, as my grandson and I are headed to Salina, KS tomorrow for a big car show.  I will not be able to take the '56 Chevy, but will still have fun

I did go out and look at the detectors after a couple of hours with the bus closed up and they were fine.  I think that points the finger at a dry "P" trap for the washer.  As I mentioned, I thought I had shot some water in it a few days ago, but I had diverted that circuit to some work I was doing on the CAC mister.  I reconnected the line to the washer drain and ran it till I heard the water going in the gray tank.  It looks like that might be the answer.  I will play with it some more when I get back.

Jim

[steve wardwell]

After poking around the net I found a list of gases that will set off a CO detector."Interfering gases of similar molecular size and chemical reactivity may produce false positive response. Major interferents that can affect CO detectors are acetylene, dimethyl sulfide, ethyl alcohol, ethylene,hydrogen cyanide, hydrogen sulfide, isopropyl alcohol, mercaptan, methyl alcohol, propane, nitrogen, and sulfur dioxide."..Found it on "fire Engineering"  forum.........s........

[steve wardwell]

safetyman, I didn't see methane on the list, although it still might not be the compleat list of all the gases to set off CO's. I too installed a new CO with the same results. Have you ever considered a nice parakeet or maybe a change in diet? 

[rv_safetyman]

Steve, thanks for looking that up.  Sewer gas has hydrogen sulfide as a component as I recall.  I think that is what makes the gas smell so bad.  Funny I did not detect even a faint hit of sewer gas smell.  The detectors must be darn sensitive.  As I recall, "Super Sniffer" did not smell anything when the system went off in Custer.

Now that you mention the chemicals, I recall having the the CO detector in the shop when I was spraying some paint and the solvent set it off.

I have a project on the drawing board for a customer that wants a better propane detector.  I was amazed at the technology and complexity of trying to get a direct reading from that type of detector.  I was also amazed at the range of gases that can be detected by one sensor.

Jim

[JohnEd]

jim,

I don't think any test going down the road is valid.  So many tiny points of air infiltration add up to a large hole and you get the interior air changed in short order.  I think you know that but there was a comment and some may not be as savvy as you.

You may have saved me from coming to a bad end.  My CO detector is AC powered and it is 10 years old. Hasn't been powered up more thn a year total over that time but is it still good?  I didn't see any caution statement about it having a life span but that prooves nothing.  My propane detector is also that old?? ?? ??

They say that the smoke detector bats need renewed every year but do they also have a lifespan? Am told that the smoke detectors are of two types....photo and ion.  The photo is labeled for my kitchen and bath and the other isn't specified.  Is one inherently better?

Thanks for the advice,

John

[JohnEd]

Hey, I just thought of this.  My CO detector gives out a chirp when my furnace first lights.  Sound like a test to you?  It has always done that...since new.

John

[JohnEd]

Can't you test the operablity of a CO sensor by simply putting pans on all the burners and lighting the gas.  Oven too.  That should produce small amts of CO and, if you remembered to put water in the pots first, do no damage.

John

[rv_safetyman]

OK folks, back to testing.

It appears that the fellow who does not know how to spell Shepherd correctly (gumpy) was the winner.  It appears that there is some sort of issue with my battery bank/inverter.  I had my super sniffer (Pat) go out with me (alarms going off) and we traced it to the battery compartment and what I am pretty sure is the hydrogen sulfide battery gas.

I had filled my batteries about a month ago with distilled water (they were lower than they should have been, but certainly not close to dry - maybe 1/2 inch below the plates).  Yesterday, I looked at the batteries and two of them probably had only 50% of the liquid!  They had been on float for several days and those two batteries were pretty warm.  Charge rate seemed to be about 10 amps (net) per the Bogart Trimetric but I would think that is normal given the pretty heavy loads that can discharge the batteries a little bit - even in the float cycle.

I am in the process of equalizing the batteries now, but that process does not seem to be going smoothly.  I have started another thread on that subject.

BTW, the new battery CO detector and the 12V CO detector have tracked very well as I do things to open and close the bus interior and the bay doors to vent the gas.  The older battery detector just sits on zero!!!  I am really upset with the way it failed (non-protective mode).

Jim

[JohnEd]

Jim,

It sounds like this adventure has led you to preventing the premature failure of your bats.  I would still determine how the H got into the cabin  in the first place and plug that up.

I asked this question before and I don't think it was answered.  If you leave the bats connected to the coach, there is only a tiny load, and you leave the charger connected......will that small trickle load keep the charger OUT OF float mode and overcharge the bats?   Even maybe if the "trickle load" was as big as the max current the charger produced and the bats were fully charged.  Wouldn't the charger just stay at 14.5 volts and pump out the current the load needed?   Seems to  me....but that can't be worth much.

John

[HighTechRedneck]

The older battery detector just sits on zero!!!  I am really upset with the way it failed (non-protective mode).

When I was doing some Google searching on this the other day to see if I could find something to help on it, I did see a statement on a site a fire safety site (I think it was a UK site) that indicated that CO detectors have a limited life span and should be replaced every 3-5 years regardless of how well they test.

[rv_safetyman]

John, my loads on my battery are often pretty substantial just sitting there.  I still have some computer items running, the house fridge (fairly large load) and other small stuff. 

The batteries are maintained by the Trace inverter which is a three stage charger.  If it is working properly, the batteries should not be overcharged.

I am concerned about why my batteries act as if they have been overcharged.  However, I will not tackle that until I get the batteries back in good conditon.

Mike, I have read the same thing on other sites (some say up to 7 years).  The two that I have are marked with the date of mfgr.  What really bothers me is the fact that they do not go bad in a mode that would let you know there is a problem.  I was not aware of the date limit, but I did do the test quite often and the results led me to believe it was working fine.

When I catch up on all of this posting, I am going to start another thread that talks about replacement.

As I said somewhere in this thread, I relied on that detector to protect us in the house with a 30 year old furnace!!!!!

Will be getting a couple of additional units in the next day or two when I get to town.

Jim

[kyle4501]

. . . .  I would still determine how the H got into the cabin  in the first place and plug that up. . . .

That would have to be some very good sealant since the hydrogen atoms are so small. 

My suggestion would be towards better ventilation (so as to diffuse it into a harmless part of the air) would be more effective. Cooler batteries last longer too.