>
>This 'boiling', is it good, bad, or indifferent?  What does it mean?

The gassing indicates overcharging.
I hope this is a wet cell. (liquid electrolyte)
If so, you just replenish with distilled water.
If it's a gel, it's damaged.

It sounds like your charger dosen't have the right voltage point set for this battery.

Here, I use a 25AH cyclon cell bank, with Samlex 25A SMPS charger.
No heating at all, no "boiling".

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