Heat Pump Water Heater In An Already Cool Walkout Basement
Our natural gas water heater from 1998 needs to be replaced in the near future (not an emergency)…The cheapest and easiest thing would be to replace it with another one just like it but I’ve been thinking about a HPWH.
I live in northern Utah 6b with a heating season that goes October through April and a cooling season that goes mid-June to mid-September (intermittently). We have 3 people in our 2600 sf (1400 main floor; 1200 basement).
I heat with a variable speed natural gas furnace (2019) but have been cutting back on combustion sources inside the home as they turn over (induction stove, HP dryer) and adding electric load (two electric vehicles) along with two separate solar systems (5kW total; 2010, 2017). My electrician loves and hates me…
My concerns:
1. The walkout basement has an open stairway to the main floor and is already too cool fall through spring.
2. I would need to run 240 volt service down to the basement or think about an external heat pump unit.
3. We have hard water with no softener (though I’ve never descaled the gas water heater).
I’ve also wondered about putting a heat-pump wall unit into the basement to keep it warmer and reduce the furnace use (and maybe compensate for the HPWH), but the heat would just go up the stairway.
Here’s a 50 second video of our house layout:
https://photos.app.goo.gl/KbYfY7JY5kxdpEaT8
I could be coming up with a multi-thousand dollar solution to a $1000 problem…
Any advice?
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Replies
In the heating season, the HPWH takes heat from the house, that's just how it works.
But your basement being cold is not an immutable fact of your house, it just means that the amount of heat being delivered to the basement is insufficient. And it's not because heat is going up the staircase, hot air only rises if it's warmer than the air it replaces, if the basement is cooler than the rest of the house air from the basement isn't going to rise.
You need to look into getting your heating system to deliver more heat to the basement. It may be as simple as adjusting the dampers on the vents twice a year when you switch over from heating to cooling and back. Or it may be more complicated, there really isn't any way to tell without experimenting.
In addition to what DC wrote, cool basements (and hot upper stories) are often due in large part to air leaks. Seal those and you'll reduce temperature stratification.