I am staying at an R.V. Resort and I am plugged into shore power. We have been here for a week with the cold temperatures. Checked my engine battery voltage and found I was just below 12 volts. Have now put on the booster switch to charge the engine batteries. My question is: How long can the switch be left on, ie for weeks provided I am on shore power or should I turn the switch on and off every few days?
Rick, Turn it on for a day, check battery, I would be concerned WHY the battery is going down, maybe someting is on such as a light/s, maybe radio or booster for tv. Not knowing how your coach is setup makes for difficulty in guessing, but again the WHY would concern me.
Good luck
A solution to your problem is TRIK-L-Start by lslproducts.com. That solved my problem.
Or a battery minder plugged into the block heater outlet.
Before I bought the battery minder, I just kept the boost switch on all the time. I checked the voltage at the starting batteries, and it was in the allowable range. The main concern is that the coach can become unplugged or trip a breaker, and you will loose all the batteries.