Originally Posted by trdutch
So if I keep the coach plugged in to run an Electric heater during winter,can I / should I disconnect the coach Batteries?
You could alternatively simply remove the fuse on the converter.Then plug it back in every couple of months for a day and fully charge the battery on a full 3 cycle charge which will keep it in good health and prevent sulphation.
I want to comment further on the battery tender. Their own website says:
"Its design is optimized for use with sealed, gas-recombinant, absorbed glass matte, lead acid batteries. It has been on the market since 1991."
Note that it does NOT mention wet cells even though it is used extensively by people with wet cells. Why...because it works in keeping the batteries topped up...pretty safely...while letting you forget about them. But the CLOSED systems it was designed for (sealed) ... are different than normal wet cells in another way.
1. agm & gell cells have little problem with sulfation and stratifiation.... so don't need big charging when in storage to prevent this
2. Sealed WET cells DO have this problem just like standard batteries but the danger of OVERCHaRGING from a standard charger greatly outweighs the stratification and sulphation concerns.
Many of you have modern battery converter/chargers from progressive or Iota that include an Equalization cycle to avoid such stratification and sulphation. But the risk of leaving them on and plugged in all winter is not worth it...so you go to something like a battery tender which prevents battery self discharge but has neither the current of voltage differential to prevent sulfation. THIS is why I continue to recommend allowing the battery to self discharge in storage for a couple of months or more in very cold weather...THEN turn the charger on and put a full charge with voltage @ 14.8 and dozens of amps instead of a couple...this stirs up the fluid and removes sulphation from the plates.
Nothing provides a safer, more carefree topping up & long term maintenance of batteries than the battery tender type products (smart trickle chargers...no dumb ones). The downside is that if used with wet cells...they do little to remedy expensive cycle life loss which REQUIRES a regular EQ or full bulk charge for WET cell batteries.
(NO...you cannot use a "tender" and then run the real charger every once in a while. You need to discharge the batteries to at least 70% and preferably 50% before you re-charge conventionally to get a bulk charge going that will do any good.)