Chassis batteries needed charging.

In my coach, the carbon monoxide & propane detectors as well as the steps are wired to the chassis batteries.....as is the engine computer....left alone, my chassis batteries will go flat in 2 -3 weeks from these parasitic loads...

Most Monaco's do not charge the engine batteries on shore power. How big/long of a jumper did you use? Many maintenance free batteries have caps, but they are under the hard plastic top and with some pressing with a screw driver they can be found... usually as a set of three.
If you clean the tops you may find some indication of how old they are and if they are Interstate they could be original.
I would disconnect one battery at a time and see if the other by itself will start your rig. I did that is past summer at a rally before the Interstate battery guys came to check my 03 batteries and had decided to not replace them BUT they let me keep my old ones so I replaced them.
PS: they are still going strong in a 24V machine at home.

Have you battery load tested - most tire/auto places with test for free. If you don't have Bird system then consider purchasing a Trik L Start - they are inexpensive, easy to install, and will maintain your coach battery.

We have found the Trik-L-Start to be a very good solution to this problem. It connects between the house and starting batteries to provide a charging current to the starting batteries anytime their voltage is less than the house batteries. It will supply up to five amps charging current. It's big brother, the Amp-L-Start, works similarly but supplies up to 15 amps charging current. What's nice is they are install and forget about them. They work as advertised.

The batteries are the "maintenance free" type. I will try charging them again and check after a half hour. They do look rather old. I replaced the coach batteries when I bought it 3 months ago.

Thanks for the info,eh?

Brad

Couple things make sure you check the water in the chassis battery, low water will cause faster discharge. 2 make sure and check voltage 10-30 minutes after you disconnect the charger as the battery will show an artificial level right after disconnecting.
3rd if you are really drawing it down that fast either you are using something you don't realize is attached to chassis not the house batteries or something could be miswired causing the extra draw.

As Mr. Wizard stated some have an interconnect some don't and some are just broke.

maybe..maybe not

some RVs have the "BIRD" system which will charge both sets from what ever source is available, giving priority to primary set of that source

BIRD = Bi-Directional Relay system

when charging from shore or generator it charges the house first then includes the chassis, after the house reaches 13.2

when charging from alternator it charges the chassis first, then the house

you may have a BIRD that has malfunctioned
or you might not have a dual control system BIRD at all

not ALL RVs have this system, mine does not