Water Heater for ADU / Main House
I need to specify a water heater for an ADU (Basement Granny Flat), and am seeking opinions from others. The contractor is recommending the Navient NCB-180E which is a conventional tankless, plus a semi-smart timer based recirculating loop.
I’m uncomfortable with the energy loss of timer based recirculation, warry of the “cold sandwich” effect without recirculation, and don’t really like having natural gas burning all the time just to keep pipes warm.
The setup is:
Basement mounted boiler
California climate zone 3
2000 square foot main house
New radiant + New baseboard heaters + Mostly new plumbing
1000 square foot ADU
New 2″ foam, 5″ slab, radiant.
Some references:
Your thoughts?
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Replies
Hi Bryce,
Have you thought about a heat-pump water heater? If not, here are a couple articles to consider: Revisiting Heat-Pump Water Heaters and The Future of Hot Water Is Heat Pumps.