LP GAS Sensor triggered by slide operation??

[Dean A Van Peursem]

This is a bit weird. My wife was going to do a little cleanup on the 3400RL after our weeks trip today. Opened the door and immediately started sliding out the slides and the 4th, the super slide, was about half way out when a piercing/painful sound started. Scared her to death. She shut off the battery switch to stop the noise. Asked me to take a look to see if something had been damaged.

Turned the DC power back on, slid the slides in and out without the noise reoccurring but on the third sequence, the terrible sound returned. This was about 3 hours later and after she had spent that time cleaning. I realized that it must be an alarm but the sound was everywhere, couldn't isolate the source. Disconnected the smoke detector over the stairs, not the problem. Finally determined it the the LP Gas detector down near the floor in the kitchen.

No gas smell anywhere and both tanks were shut off tight yesterday. Checked all gas connections I could find, no detectable leak anywhere. Decided to close up the RV and turn both tanks on and waited awhile. Exercised all the slides, no reoccurence. Of course!

I'm really confused, what the heck is going on? The only thing I can think of is the possibilty of some kind of gas being emitted by the slides or the DC power (LP Gas detector is powered by 12V battery power from the RV) is being interferred with by the slides somehow. Very strange??? Help???

In the process of messing with the slides so often during testing, the slides now don't open nice and sequentially like they used to. Now some slides start in parallel and then complete when another slide is fully extended. I have no idea what I have done to cause that either. I did try operating each slide individually by turning off the valves to the other three. That works as it is supposed to. Not all that serious a problem I guess, but sure is different than it was originally!

The gremlins are after us! :-)

[315RLS]

I'd hazard a guess that you are not hooked to shore power and when the slides are opened the draw on the battery causes it to drop below the minimum charge required by the detector causing it to trip. If this is the case I would expect that by leaving the trailer sitting for a few more days without charging the battery and you'll find the alarm trips on its own without the action of the slide just from the continued drain of the flashlight, detector and anything else that may be drawing from the battery.

[Dean A Van Peursem]

This may be possible but at present I'm having a hard time believing it. We were hooked to shore power for a week up till Monday night. So to have the batteries drain down that much in one day is difficult to believe, especially with the batteries disconnected. Battery indicator shows full charge. Now a poor connection (high resistence) causing the voltage to drop too much setting off the LP gas detector I could believe.

[uhftx]

I don't believe its so much a bad connection. The slide hydraulic pump draws significant power from the battery. The wire run from the pump to the battery is very short. The path of least resistance. By exercising the slide you are drawing more power than the converter can make up to recharge the battery.

The LP gas detector does behave just like a low DC voltage alarm. I experienced this in my last camper also. They must use a comparator op-amp. When the two voltages being compared (sensor and a reference voltage) the alarm trips. By having low DC power being supplied to the LP gas detector. This comparator circuit voltage threshold is met causing the alarm to sound.

I briefly explained this after the Tornado warning and power failure episode at the NE rally last year in Lake George NY.

[OntMont]

I am leaning towards the transient low voltage theory also. If there was no gas in the area, then that seems the most likely cause, especially if you were not hooked up to shore powerer at the time. Could you re-enact the situation with a volt meter attached to, say, one of the 12v lights or some other convenient spot, but not directly on the battery? If it is low voltage, it is something to know about.

[Dean A Van Peursem]

Ok, Thanks for all the responses. I'll try to find a spot to monitor the voltage output at a remote 12V point while operating the slides. This should indicate if the 12V is dropping a significant amount within the RV during slide operation. If the electronics inside the LP Gas detector is a voltage comparator it might be a little sensitive to voltage drops. However, I'm a bit curious as to why the situation would show up at this time when the batteries are charged the most they ever have been.

PS: All during these occurrences we were not hooked to shore power.

[Montana_1240]

It sure may be voltage, or an overly sensitive sensor. Try hooking it up to your TV while the TV's running.

If it still occurs, (and there's no break in any flexible line that runs to your stove in that kitchen slide,) then I'd be having that sensor checked, with an eye to replacing it.

Steve