Heat Pumps Take on Cold Climates • Hacker News Board

Re: Heat Pumps Take on Cold Climates

#81

Post by electric_mayhem » Thu, Feb 29, 2024, 6:31 PM UTC

hazmazlaz wrote: post #78

voisin wrote: post #76

Earlier quoted context omitted.

Can you give more detail about your system and in particular the thermostat that makes these adjustments? Sounds interesting!

Seconded, I also want to know the model of thermostat they're using!

Heat pump is a Trane XV19 and the thermostat is an xl 1050 (supposedly trane but my understanding is it’s a rebranded Nexia)

The process to update the costs (which has to be done a few times per year when my utility changes their rates) is not very user friendly - have to get into the technician menus and change scary looking stuff) but it works quite well.

Re: Heat Pumps Take on Cold Climates

#82

Post by goalieca » Sat, Mar 02, 2024, 2:45 AM UTC

timbit42 wrote: post #73

goalieca wrote: post #53

Earlier quoted context omitted.

A huge chunk of canadas population in Quebec, Ontario, prairies, and BC see -20 for weeks on end. -40 is more rare but happens every year. Huge chunks of the mid-western USA see those as well. At -30 my furnace is basically on continuously.

How many days/nights do they see -40C? Even if it's 30 days straight, a heat pump would work the other 335 days of the year.

One night at -40 when the heat pump is shut off is enough to freeze pipes and cause serious damage.

Re: Heat Pumps Take on Cold Climates

#83

Post by _yb2s » Tue, Mar 05, 2024, 7:29 PM UTC

simonblack wrote: post #80

_yb2s wrote: post #71

Earlier quoted context omitted.

Why they would be obsolete if more efficient than regular natural gas heat, which is by far the currently most widely used home heating technology?

:) When did you last see a kerosene-powered fridge? It's about 40 years since I last saw one. Hence my 'obsolete technology' label. Reverse-cycle (heating) heat-pumps rely on fans to extract the heat away from the machine and send warm air into the room. If you have electricity for the fans, you might as well use that electricity to power the heat-pump too.

modern RVs still widely use propane powered absorption refrigeration, although that is starting to move over to solar and battery arrays.

The fans are a tiny part of the energy used by a heat pump, most of the energy is for running the compressor. Electric heat pumps are more efficient and economical than electric heat, but still generally more expensive than gas heat, and impractical compared to gas if that electricity itself is made from gas in the first place.

If you power a heat pump with gas directly, you are effectively getting over 100% efficiency: you keep all of the heat generated from the gas, plus are 'pumping' heat from outside. It's going to be even more economical than regular gas heat, which is already more economical than anything else.