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Venting of mid efficiency via chimney
The current water heater is a 20yo gas fired tank atmospheric vented into a masonry chimney with single wall 26ga 3" pipe. Its making those wonderful gurgling sounds whenever a faucet is opened.
I'm looking to replace it with something with a higher efficiency but not necessarily a condensing unit.
Maybe a mid efficiency tank or tankless.
I looked at the Rheem EcoSense direct vent but the venting accessories are all double wall steel and I'm assuming that its a coaxial setup where supply air is brought in via that piping. I wouldn't be able to support the piping every 4' as required in the instruction so that's a no go.
Mid or high efficiency, masonry chimney vented, tank or tankless.