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Should there be a buffer tank on this type of job?
Home owner is building an new house. Wants to install an Navien 240 combi boiler. The home owner wants one zone radiant and the rest of the house copper baseboard.
In the kitchen they want radiant as one zone by itself. Then three other rooms on the first floor as another zone.
Second floor master bedroom one zone by itself. Then two bedrooms and master bathroom and other full bathroom as another zone.
Only kitchen getting radiant with the other three zones copper baseboard.
Heating contractor wants me to price regular copper baseboard and I will but I will also be quoting him on the heating Edge HE3 copper baseboard so they can use as low of water temp to heat the house and try to get the boiler to actually condense most of the heating season.
With these small zones should this type of job have an 30 or 50 gallon buffet tank? I would say yes.
If installing an buffer tank would it make sense to have a coil in the buffer tank so during the heating season and that tank is up to temp run their domestic cold water through that coil picking up some heat and then running it into the Navien combi boiler where that will make all the domestic hot water?
If this was my house I would be installing the buffer tank no questions asked adding a coil to the buffer tank would be up for discussion.