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I am installing a gas boiler with 2 zones the house never had one it had a space heater so I am installing evrything the boiler manual says to install the expansion tank 18" away from the boiler, the boiler is in a tight spot how important is the 18"? I cannot find any info online related to exact locations for the install does it need to be above the boiler?
I have a 47000 btu gas boiler 2 zones heating a 2nd flooor apartment boiler is in the basement about 45 feet of baseboard