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Comment by prepend | Hacker News Reader

I had a furnace die and had to replace it last year. The hvac company was really down on heatpumps and said that due to the climate (doesn’t get too cold in the winters gets really hot and muggy in the summers) the heat pump would be less efficient than a traditional furnace and AC.

I like my hvac company so didn’t push too hard but wondered if this was true or just their inexperience.

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If it doesn't get very cold in winter that is ideal for a heat pump. Heat pumps lose efficiency as it gets cold, and even the best stop working completely at somewhere around -20. If it might get that cold you need a backup source of heat.

HVAC companies don't like heat pumps because they cost more (mostly for no good reason - but you may need a larger heat pump and air conditioner), don't put out as warm of air as a gas furnace, and are slow to change temperatures (don't not get a setback thermostat with a heat pump!). Customers do not understand them and end up unhappy and complain about them. However if you get one anyway understanding the limits you will save a lot of money.

Taking it a step further it makes sense.

So far most heat pumps are a step up in price in the US compared to the traditional furnance/Ac setup. If you only needed the furnace replaced it might make sense to only replace that and not spending the extra multiple to replace the entire system.

Lies like that make my blood boil. Not-too-cold winters are perfect for heat pumps.

They don't like heat pumps mainly because their customers "don't feel the heat" from them. The heat comes out at lower than body temperature (85F/30C) so the customers don't feel like they're really working, whereas a gas furnace or electric heater usually heats to 120F/50C. So, customer satisfaction is often lower even though they are saving money and polluting less. But, you know, that 85F is plenty to heat a room to 72F and keep you warm.

Our Mitsubishi Hyper Heat heat pumps put out noticeably warm air, definitely warmer than 30C.

That sounds nice. They are mini split or ducted?

I can't imagine that a traditional furnace and AC could be less efficient than a heat pump, unless you almost never turn your heat on—a heat pump is many times more efficient, in terms of energy consumption, than a traditional furnace.

That said, if it's rare to run your heating then a standard AC unit is probably marginally more efficient than a heat pump for just the cooling operation

If you already have AC ducting/plumbing, you're an ideal candidate for "reversible AC" heatpumps.

Not inexperience. Motivated reasoning.

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