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Comment by notdarkyet | Hacker News Reader

I see this as well and it looks to be multiple people buying in to the campaign, especially here on HN.

Having lived in a new, high end apartment that had a heat pump for both heating and cooling for 3 years, I am very unimpressed with the tech. Running nonstop, couldn't heat/cool above/below a certain threshold. Electric bill very high. Clogged and broke a lot. If the general radiant heat and cooling from being in large building didn't exist, I couldn't see this working halfway decent in any place in the midwest. This might work for areas with less variable temperature ranges but for the midwest USA, not seeing it.

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Your singular experience is an outlier, not an example of totally normal circumstances.

There is no conspiracy to push broken technology on to the masses. Heat pump technology has come a long way and modern heat pumps are very good at what they do.

If someone installed a heat pump that doesn’t work in the temperature range of your location, they really screwed up. Modern heat pumps can be selected to work down to very low temperatures, and they’re installed with auxiliary heat when necessary. The design parameters aren’t a mystery.

Your high end apartment must have had a low end heat pump installed.

In the midwest a geothermal heat pump would work wonderfully.

Also, they are designed to run constantly in order to maintain the set temperature -- it's not like a natural gas fired furnace where it quickly reaches the set point.

> Also, they are designed to run constantly in order to maintain the set temperature

Not all heat pumps are variable-speed like you describe. My own home, built in 2000, has a single-speed heat pump that kicks on 100% or off, like a regular old AC unit.

Right, what I'm trying to say is that it is normal for it to be on 100% of the time when it is cold out. If you are used to gas heat which can turn on for 15 minutes, overshoot the set point, and then be off for the next 45 minutes, a heat pump will seem strange.

Mine is a variable speed unit, but that's not the function that I'm talking about.

What's the payback time on something like that for a modest home in a place which can get significantly under 20 degrees (F) or over 95 degrees for weeks or longer? How effective is it at those extreme temperatures when it matters the most, and how does this affect maintenance costs?

Additionally, there are multiple types of restrictions on where geothermal pumps can be installed, and navigating this can add to costs.

I don't see it as a one size fits all solution, there are far too many people for whom the household/company math doesn't add up. However, I agree we should be doing fair comparison against other renewable-friendly options for all new construction. I'm sure heat pumps could win out in a great many situations, and we should use them where they do.

Obviously nobody can answer the long term cost differences between gas and heat pumps, since the cost of natural gas and electricity can change drastically over the lifetime of the unit.

GP's comment was about the tech, though, and not the cost of said tech.

It's absolutely not a perfect solution for all heating needs across the globe, the the technology is far better than GP is suggesting.

In my view, natural gas is only competitive due to externalized costs and the slowdown/freeze of nuclear energy deployment. I recognize it's the only option for all kinds of situations (my dwelling heat included), but for anyone thinking forward it should be excluded in future development where possible.

My main concern is the overall long term efficiency & affordability of renewable-friendly solutions, because competitiveness in those areas is what will lead to mass adoption. The point I was hewing toward is that I feel the heat pump advocates and providers need to make it more clear which situations are best suited for that solution and which are not, because it would benefit everyone.

> over 95 degrees

Note that a heat pump cooling a building is essentially the same as an air conditioner. So it's more a matter of how efficient the air conditioner you're replacing is. Cooling a house is much easier than heating, because the temperature differences are lower. In your example, cooling 95 F to 70 F is a 25 F difference, while heating 20 F to 70 F is a 50 F difference. The world record for heat is about 135 F, which is the same difference from 70 F as 5 F, a completely normal winter temperature in much of the world.

The constant running also affords a more consistent temperature because air is continually moving. Decreases the temperature variance throughout the zone. I have a 3 zone heat pump, 2 single room zones upstairs and a main floor with a air handler. We LOVE the setup so far.

Yes, I've been happy with ours and it was a great improvement over the last heat pump that we had.

Habits are hard to break, though, and there's not much value (if any) of lowering the set-point at night during the winter months. People still do it, though, and then the unit is working overtime in the morning to reach the desired set point.

I'm glad that you're happy with your setup!

Just to clarify, it is more efficient to lower the set-point in the winter over night. The issue is when your thermostat is set to utilize aux heat if the delta is higher than your set point change in the morning. For example. If you change from 70 to 67 at night. In the morning when the set point goes back to 70, the thermostat is likely configured with an aux delta of 2 or 3 degrees. Meaning every morning the expensive resistive heater is running to raise your temp quickly.

Personally, for my home and climate in the area, I disabled aux heat entirely, unless the temperature is below 0f outside, or if it hasn't reached the set point within 2 hours. Recently had some cold weather and these settings worked well for my home.

I'm using an Ecobee, configurations will vary per thermostat. The big settings for me were using manual staging to configure the temperatures to engage aux, temps to lock it out, etc.

Also remember that air-to-air heat pumps are overall less efficient and powerful than air-to-water or geothermal-to-water type heat pumps.

Firstly the later typically have a higher power rating.

Secondly, if you can lead water around the house and heat via radiators or floor heating you get a much better efficiency.

This is not the common experience, it's just an AC that runs in reverse. It sounds like a bad install/bad equipment.

Have you considered that you bought the heat pump equivalent of a Ford Edsel, rather than the tech being fundamentally bad?

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