Hot Water Base Box- replace?
 

Has anyone who used a plumbing company to replace their water heater also replaced the base box under their water heater when they got a new one?
Our water heater is in the garage and the wooden base box looks pretty beat up.

wood? i would suggest that the base be strong enough to support 40-50 gallons of water and the water heater..12-15 years is along time....8.3 pounds per gallon plus all
the extra chlorine added to kill the germs.. Lowes and Home depot sell very nice metal
bases ... plumbers dream

As long as the wood base is supporting the water heater, I wouldn't replace it. I doubt that a plumber will want to tear it out, but maybe you can find one who will.

That base box is also your return air duct.

Not the one under the water heater. You may be thinking of the wood box under the HVAC unit.