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boiler and hot water venting

3K views 3 replies 2 participants last post by  AllanJ 
#1 ·
Hey All,

Had a quick question for the experts out there. So i currently have an AO Smith oil steam boiler that has my hot water heater integrated into the unit. I would like to purchase a natural gas hot water heater and decommission the hot water heater part of the boiler.

Can the Natural Gas hot water heater and the Oil Boiler share the same chimney vent? and how difficult is it to decommission the old hot water heater? Thanks in advance for the help!
 
#2 · (Edited)
In most cases the new water heater and furnace can share the same vent (flue). The water heater installer should inspect the vent to see that it is big enough.

To decommission the boiler built in (tankless?) water heater, just leave both inlet and outlet disconnected. Boiler water is not commingled with domestic hot water so the heater pipes are not interconnected with the boiler interior. Should boiler water leak via the water heater inlet and outlet, cap them off.
 
#4 ·
The boiler has to stay hot to heat the house in winter anyway.

In the summer, shut off the power switch or the circuit breaker for the boiler.

Sometimes but not always the built in water heater has its own "zone" and you can undo the electric wires from that thermostat to prevent extra effort to heat domestic water.

Yes the built in water heater should be drained when decommissioned. When it is disconnected, it may drain itself enough.
 
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