Hi, I am designing a small home for my daughter and your family in Inverness, CA, a small town about an hour north of San Francisco. They would like to have radiant heat for their heating system, so I have designed the 1200 SF house using Warm Board floor panels. The house is required to have a solar system per California Tile 24 requirements. The issue I am having is what is the best way to heat the floor and handle domestic hot water. Per California Tile 24, an electric instant hot water heater won’t work, so I’m leaning towards either a heat pump type water heater but am not sure what to specify. The house will have R-3o Floors, R-21 walls and R-40 Roofs. Does anyone out there have any suggestions or know someone I could hire to design the most efficient system for them. Natural gas is not available, so it’s either electric or propane. I would appreciate any help you brainiacs out there have for this pretty mild climate.
Thanks,
Paul
Replies
Geothermal heat pump with excess heat to preheat electric water heater. Extra solar panels to cover electric water heater and heat pump energy requirements. For solar system you have to have a battery backup and I would also add a Generac or similar type of standby generator for those days when PG&E just turns off the grid
Thanks for the reply. So you don't think a heat pump water heater would be energy efficient enough, like the Sanco 2 or similar type of water heater? Unfortunately their lot is very steep (35%), so a geothermal system is out of the realm of possibility and cost.
Thanks,
Paul
Start with a manual J calculation for the expected heat load your house will need in the location.
Having a number for the actual heating BTU you need for the house, you can size the system.
Before you discount a ground source heat pump, get the holes in the ground priced. some land will have to be moved around for the house and driveway. might be a way to phase the hole drilling in the process.
Either a ground or air source heat pump can be sized to work.
A local source for installation and service will be needed. (but it seems you already know that)
You may be able to include some direct solar water heating in the mix. (in addition to the electric panels.)