CO and propane detectors go off when battery disconnect switch turned on

[vetrad]

2020 Intech Sol horizon Trailer. Bought used from a friend who used in a handful of times about a year ago and has sat unused (plugged in, battery disconnect off) for the last year outside at my home. The thing is practically unused and has never even had waste in the blackwater tank. I plan on using more regularly soon and have been testing it out. I've noticed if I turn the battery disconnect switch on for 12 volt power, the hard-wired, baseboard mounted, propane detector would go off after a few hours (it's a CO/propane alarm but giving the propane alert). I replaced it and that seemed to go away. Then the ceiling mounted, battery powered CO detector started going off after about 12 hours of sitting there with the disconnect switch on. Propane is off at the tanks and everything (furnace, AC, water heater, stove, frig) has not been used in the last year. Both detectors are well within their expiration and seem to work properly. They are definitely giving the detection alarm and not a maintenance/test chirp. The battery powered CO alarm goes off repeatedly when the disconnect switch is on and the camper is closed up for 12-36 hours. The alarm does not go off when the disconnect switch is off and plugged into shore power. Any thoughts on what could be triggering them? The thing still smells new and gives some odors. Batteries look good but could give off gas? We are not using the shower. Trying to find a link between the CO/propane detectors and turning on the battery disconnect switch even when all appliances are off. I want to make sure it's safe to use. Thank you!

 

[Henry J Fate]

When you say "battery disconnect is off" does this mean battery power is now available in the trailer ?

You said you replaced the lower wall mounted co/propane detector and the problem with that unit has ceased.

The ceiling co unit is battery powered only. Did you replace the battery to eliminate that as a possibility?

If battery replacement to the ceiling unit fails, the ceiling co detector may also need a replacement.

 

[vetrad]

For correction, I have a 2022 trailer, not 2020. I'm new to this so I may not be using the correct lingo. When I'm saying battery disconnect is off, I mean the switch is off and not providing battery power to the trailer. I'll attach a picture in case I am using the wrong words. The alarms only go off when this wall switch is put in the "on" position.

I replaced the hardwired lower wall mount co/propane detector, but I accidently replaced it with a propane only detector (I'm going to put in a new co/propane detector soon since I don't mind the redundancy). The original unit had a constant red light during the alarm indicating it was detecting propane (not flashing light for CO). I only have one CO detector currently in the trailer.

I did replace the batteries in the ceiling unit and it still has the problem. I've ordered a new unit for replacement and it will be here tomorrow.

Just seemed weird that I'd have two detectors give false alarms when each are 2 years from their expiration date. It seems like they are detecting something to trigger them because they give false alarms under consistent circumstances. I'm a rookie and want to make sure I'm not overlooking something someone with more experience may see as a red flag. I should have two new detectors installed tomorrow and I will see if the problem persists. Thanks!

 

[Laura & Charles]

Welcome to the forums! Lots of friendly and knowledgeable folks here! (Most know more than me… they’ll be along shortly.)
Have you checked the batteries soc? (State of charge) Someone will confirm or correct me, but I believe if your disconnect was off, having it plugged in wasn’t charging your batteries. If so, they may be dead and CO and propane detectors will alert if they have low power.

 

[Old Mud]

Welcome aboard Vetrad, Both Henry and Charles have good points.

When you say this "The thing still smells new and gives some odors." and this "It seems like they are detecting something to trigger them because they give false alarms under consistent circumstances" I think of maybe they are not false alarms. That new smell you talk of may be the culprit. Have you aired out the unit before trying the tests ? Just a thought . After using contact bond a few years ago and even after airing it out the alarms would act funky and go off occasionally. After much ventilation they ceases to give "False alarms" which were in fact not false after all. Just a thought.

Don

 

[Kirk]

Batteries look good but could give off gas?

The answer to this is yes, batteries can off-gas and trigger the alarms. If the trailer sat for long enough with no batter use and not charging supplied it is possible that they were damaged. It is also possible that the electrolyte levels are so low that battery plates are partially uncovered and either of those can cause batteries to off-gas. The alarm on the ceiling is a smoke detector and CO detector. I have experienced alarms caused by battery off-gassing. When you say that the batteries When a wet cell battery makes gas it has several components and hydrogen is one of them. Hydrogen is a colorless and odorless gas, similar to CO, and CO detectors can activate when exposed to high levels of it. This can be a potential explosion hazard.

 

[CharlesinGA]

The batteries may be bad. New trailers will have a multistage converter/charger and will not cook the batteries, and some units such as Progressive Dynamics converters used in some new models, will have a desulfating mode built into them. The batteries will last much longer if left turned on when plugged in to shore power. (note for other readers: this is not true if you have an older single stage or constant voltage converter/charger (which you really should replace))

That being said, and back to your immediate problem, high humidity will set off CO detectors, I've had it happen. Don't know what the weather conditions are where you are located.

Charles

 

[vetrad]

I think you are on to something with the batteries. There are two, deep-cycle lead acetate batteries. I can hear a faint bubbling noise from the batteries constantly, both during charging and when left isolated. According to my RV control center the batteries are fully charged (all 4 lights illuminated). When I apply a voltmeter across the battery terminals with the dial turned to 20 V DC, I get a reading of 6.25 volts with the disconnect switch "off". When I turn the switch to "on" I get a reading of about 6.45 v. I am interpreting this to mean the batteries are bad and should have closer to 12-13 v reading on this setting. I think this also suggests the batteries only charge when the disconnect switch is in the "on" position.

Is this enough information to confirm the batteries are bad and need to be replaced? Is it worth opening the batteries and checking the battery fluid levels? If I recall, you can refill them with deionized water. Thanks again.

 

[vetrad]

Oops, my mistake. I realized the batteries are connected in series and when I take a reading from the negative on one battery to the positive on the other it is 12.75 volts. This seems normal? Not sure what to make of the bubbling noise but certainly could be hydrogen gas. Google says it could be a problem or could be normal. The batteries are functioning fine. Any other ways to test if the batteries are a source of the gas issue?

For background, I am in California where the peak summer temps can get up to 95-100 F. It's a dry climate. The original owner of the trailer was in Idaho and kept it inside a barn. It has been exposed to a season of below freezing temperatures but it was winterized by the dealer for it. I'll be picking up another CO/propane detector and installing it this evening. Thanks again for any advice.

 

[CharlesinGA]

Are those batteries in a compartment sealed from the rest of the trailer? You CANNOT have lead acid batteries inside the living area of the trailer (ie. under a dinette seat, etc) due to their production of hydrogen. If you are not familiar with the fill procedure, they should only be topped with distilled water (easily found at Walmart) and water added to the "ring" inside the fill port of each cell.

The slots in the ring allow for venting, Never let the plates become exposed/dry on top.

Charles

 

[vetrad]

Batteries are under a dinette seat. it's where they were installed by Intech. They have a passive vent through the black tube in the picture. There is about a 1 inch gap along the leading edge of the white cover and the hole. Sounds like a design flaw could be causing this?

 

[Old Mud]

WOAH. those batteries do not belong there. Even with that small vent. They should be completely sealed from the inside living area and constantly vented to the outside. I'll bet the farm on that being your problem. A picture really is worth a thousand words.

Don

 

[gwinger]

That tube is doing nothing to vent the batteries unless there is fan on the tube to pull the fumes to the outside. Strange setup. The batteries produce highly flammable hydrogen gas. Think of the Hindenburg.

 

[John From Detroit]

I agree something is tripping them.
Smoke alarms. Depending on where you live due to WileFires if they are senisitive enough.. Yup. I an see that. never heard of it but I can see that.

Propane: These are Really "Explosive Gas" alarms. Propane, butane, Methane (That's a..er.. Natural Gas) Alcohol. Some cleaning products. Not sure about Sulfur Dioxide (Battery gas) But you do need to figure it out.

 

[CharlesinGA]

The only kind of batteries that belong in there are AGM or Lithium. The boxes are not sealed, the gasses (hydrogen among others) just leak out and (somehow) exit thru the vent tube, but everywhere else also.

Clearly that is setting off the LP detector. Not sure why the CO detector would be going off however. The batteries should not be bubbling noticeably so I'm guessing they are not in real good condition from sitting.

If you don't want to do the changeover to Lithium (new converter, special class T fuses, heavier cables, inverter, solar, etc., consider GC2 size AGM batteries such as those by Full River which are true Deep Cycle batteries and will last a long time if you treat them right.

Fullriver DC224-6 6V 224Ah Deep Cycle AGM Battery (Group GC2)

Charles

 

[vetrad]

Thanks Charles, Don and everyone else for their opinions. I installed a new CO/smoke and CO/Propane detector today. I'll let it sit until Monday and see what happens.

Assuming I continue to pinpoint the batteries as the problem, I would rather switch over to Lithium and get an inverter/solar so I can run my AC and 120 volt outlets when disconnected from shore power. Do you have a reference or source I can use to help me do this? I have a 2022 Intech Sol Horizon 19 foot trailer with a 30 watt plug.

BTW, the smell I mentioned I think is the adhesive from the flooring and caulking in the shower. It seems to be a typical complaint from other with this trailer.

 

[Arch Hoagland]

Did you add water to that battery in the picture?

 

[CharlesinGA]

Running the A/C off of Lithium for any practical length of time is not something you can do with a couple of batteries. You would need 10K amp hrs of battery to have any success with that.

 

[vetrad]

Both new CO detectors had their alarms going off within a few hours. Not sure where they could be detecting CO but perhaps it's hydrogen from battery gas. I did not add water to the batteries. The water level is about 1.5 inches from the tippy top but all the plates were still covered. I do not see anything to indicate where the level should be?

Thanks for the link to the video about the AC. I will check it out.

 

[Kirk]

You CANNOT have lead acid batteries inside the living area of the trailer (ie. under a dinette seat, etc) due to their production of hydrogen.

That isn't true if the batteries are properly ventilated. I has been very common to put batteries under the inside step of class A RVs for years but the space is usually pretty much open at the bottom.

Both new CO detectors had their alarms going off within a few hours. Not sure where they could be detecting CO but perhaps it's hydrogen from battery gas. I did not add water to the batteries. The water level is about 1.5 inches from the tippy top but all the plates were still covered. I do not see anything to indicate where the level should be?

While ventilation of the battery storage space is very important, if things were working with no alarms before and are now alarming, then something must have changed. If you can plug the trailer in so that your converter supplies 12V power, I would remove both of your batteries from the trailer and see if it still alarms. That will give you an absolute answer to whether the batteries are the cause or not. That way you won't be chasing ghosts, but will answer the battery question for sure.