I group 24 should last more then one or two days. It is possible that the battery was not fully charged.
Check to see what model refer you have. Some rigs have a 12 volt DC heating element. This can drain a battery very quickly. Next check to see if it has humity switch(?). What is make and model of refer? Current eastern Washington hot weather can play havoc on refer!
Your rig most likely does not have an "inverter" but is equipped with a "converter".
Switching to LED lamps can save much battery power.
What part of central Washington?