more heat pump questions

[macphanatic]

Look at Reddit for heat pump horror stories about increased electric bills. Not saying that this will be the case with all heat pumps. Just make sure that you educate yourself before making the change. Like solar, there are a lot of shady contractors pushing heat pumps, especially in areas that get cold and have higher electricity costs.

[Cary]

I installed a new HVAC/hi efficiency heat pump in my previous house e-4 years ago, left the gas boiler in place as a back up.

Ecobee helped me set up the thermostat so the the heat pump was primary and gas boiler was secondary when the heat pump couldn’t satisfy demand.

System worked well. Energy savings were small, but the house was comfortable…

[Fritz]

Cary wrote:
I installed a new HVAC/hi efficiency heat pump in my previous house e-4 years ago, left the gas boiler in place as a back up.

that's pretty much what the HP installer said to me.

But then I got this response, long and technical from an HVAC tech.
https://www.hvacsite.com/threads/gas-fur...pump.6464/

it's about efficiency of HP as the temp drops and how it needs to make more than what it is set for.

I'm on the fence

[Cary]

Interesting… - thanks for sharing.

[Fritz]

2 new wall ACs would be a whole lot less than HP install.

[Fritz]

and I'm not sure the carbon footprint is any better.
How is the electricity made? 80% of the US is fossil, NG, coal.
20% is renewable. Here on LI, I'd guess 100% fossil.

[kj]

Fritz wrote:
and I'm not sure the carbon footprint is any better.
How is the electricity made? 80% of the US is fossil, NG, coal.
20% is renewable. Here on LI, I'd guess 100% fossil.

I think because it's a lot more efficient, even if it uses natural gas produced electric it would be better. But around here, it would be a lot better because we hardly use any dirty power (although hydro is very damaging to the environment in its own ways).

[Fritz]

but efficiency drops working to heat to 68º when the outside is <40º.
and cool from 90º to 72º.
dunno what the trade-offs are, math wise, but I begin to wonder