I need a new water heater and one plumber says the expansion tank on the side is not necessary. Is it? What is the average cost of a 40 gal, under air water heater already hard wired? 2nd floor. Thanks

I need a new water heater and one plumber says the expansion tank on the side is not necessary. Is it? What is the average cost of a 40 gal, under air water heater already hard wired? 2nd floor. Thanks

I don't give estimates. Too many variables. What's a under air water heater that's already hard wired? If you have a check valve or a backflow preventer on yourwater service you will need a expansion tank. Regards, Tom

I meant an under the air conditioner water heater. It's 31" high. It has an expansion tank to the right of it. I need a new Hot Water Heater, but some plumbers say the expansion tank isn't necessary. I'm on the second floor of a condo. Thanks for your first reply.