Replacing old CO alarm in AF990

I have 2 of these:

Kidde Co detectors

They now have them with a 10 year lithium battery.

Kidde Co detector with lithium battery.

Jim

To follow up on my original post, I removed the old CO monitor and followed the wires into the junction box in the closet. Turns out the 2 red wires on the old detector were connected to a single purple wire. The black wire on the old unit was connected to a white wire on the camper side. I checked the power to the unit by disconnecting shore power and leaving battery on and the green light stayed on. I then turned the batteries off and plugged in shore power and the green light stayed on. Then turned on battery and shore power and green light stayed on.

I then connected the single red wire on the new CO detector to the purple wire and the black to the white. The new detector stayed on with all of the same on/off scenarios as above.

I guess the purple wire must be a 12 volt feed that the converter system keeps hot by whatever means it determines and keeps the detector functioning as long as there is any power available to the converter.

I will probably get a battery powered unit as others mentioned as a fail safe. You only die once and I want to delay that as long as possible. Thanks to all who responded.

Lets not mix up CO detectors with LP/Propane alarms.

Noel has it right. CO detectors are the most important safety equipment you can buy. I have dtwo.One up high and one down low. CO is the silent killer. Spend the money to back-up the wired ones with 2 battery operated ones. Could save your life

We had a AF 1150 years ago and bought two battery powered CO detectors which are MUCH MORE sensitive than the original one.

Still have them and if anyone is interested I will post Mfr and model#

Well short of contacting AF for a wiring diagram/replacement recommendation or SafeTAlert for recommendation I would test the leads and insure one you use is always hot irregardless. IE with shore power/without, battery etc.
Most info Ive seen just recommends connecting to camper power supply (without identifying which one) and cap remaining wire, some RVs just had multiple 12v input wires. However, to be sure, I didn't note model numbers, some CCI third wire (yellow I think) was to solenoid valve that shut off gas...if thats the case a little more involved.
As a lot of these older CCI have been replaced (or need to be) I'm surprised theres not more definitive how tos.
edit did find this cross/over link
http://www.mtidealer.com/images/MTI-CCI-Cross-List-Propane-Alarms-2012.pdf