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Heat pumps of the 1800s are becoming the technology of the future

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Re: Heat pumps of the 1800s are becoming the technology of the future

#301
post #290

Earlier quoted context omitted.

Depends on your frame of reference but in Melbourne it can get to around 1 degree Celcius in winter (33~F). Sometimes subzero but very rarely

In upstate NY it gets a lot colder than that https://en.wikipedia.org/wiki/Syracuse,_New_York#/media/File... the average temperature is below freezing for four months.

That actually sounds like a perfect climate for it.

Re: Heat pumps of the 1800s are becoming the technology of the future

#302

People in the UK are talking about the risk of heat pump installations being in the tens of thousands & not possible everywhere. This is mostly from anti-green MPs. Anyone know what the facts are there?

There are some videos on this YT channel about that: https://www.youtube.com/@EverythingElectricShow

Re: Heat pumps of the 1800s are becoming the technology of the future

#303

Earlier quoted context omitted.

Mitsubishi Electric or Mitsubishi Heavy Industries? I sourced opinions far and wide and in the end it seemed to be a coin toss between Mitsubishi Electric and Daikin. A lot of it comes done to parts availability, and both seem very strong in Australia.

I live in a cold climate

Mitsubishi is gold standard in cold climates. It’ll pull heat from -30F air.

Re: Heat pumps of the 1800s are becoming the technology of the future

#304
post #168

Earlier quoted context omitted.

Can't heat with gas without electricity, unless you have a genset or power wall kind of thing to provide epower.

Until a couple years ago we had a gas-fired tankless water heater which used a single D-cell battery for ignition, which had to be changed once every year or two. It wasn't connected to wall power at all.

But you need a blower or pump in order to circulate heat in a house. Hot water is better than nothing but it won't keep your fish from freezing.

Re: Heat pumps of the 1800s are becoming the technology of the future

#305

In a house I own in Melbourne, Australia, I just replaced an old gas central heating system with 3 new top of the line Daikin mini split heat pumps. The new units can heat the entire house for the same amount of electrical energy that was used to run the FAN in the old gas unit. They are crazy efficient. Ducts are dead. The Daikin Alira X is the gold-plated option and cost $8k AUD for 2x2.5kw and 1x7.1kw units includ…

Regional Vic for me, Daikin Alira X's installed in rooms about a month or two ago, and they've been great. Very energy efficient, and individual units in each room means we can match everyone's preferred climate -- even heating one room while cooling another! Main downside is that you need space for more inverter units outside.

They're pretty quiet, too. You can certainly hear the air coming out, but it's fairly quiet and certainly wouldn't be noisy enough to bother you over tv, work, or anything else.

Re: Heat pumps of the 1800s are becoming the technology of the future

#306
post #277

Earlier quoted context omitted.

Because it smells bad inside? Because fresh air feels good? Not to be snarky, but how did you miss these use cases?

If it's pretty cold outside, then you're throwing all of the ostensible energy savings of a heat pump out the window the minute you open it to air out the house. Following the thread of conversation, it just didn't compute to me: >>>> Heat pumps are great for climate control >>> Yeah, ducts are dead >> What if you want to recirculate air in your house through your central air filter to eliminate smells? > Just open t…

For an existing dwelling, the best solution is probably mini splits (wall mounted) combined with decentralised heat recovery ventilation as required.

Ducts running in an insulated space are sources of huge energy loss.

Re: Heat pumps of the 1800s are becoming the technology of the future

#307

In a house I own in Melbourne, Australia, I just replaced an old gas central heating system with 3 new top of the line Daikin mini split heat pumps. The new units can heat the entire house for the same amount of electrical energy that was used to run the FAN in the old gas unit. They are crazy efficient. Ducts are dead. The Daikin Alira X is the gold-plated option and cost $8k AUD for 2x2.5kw and 1x7.1kw units includ…

Are you asking why the Daikin Alira X is more expensive in the US? It's because it's not a brand that is normally found here. If you went with a common US brand you can get a good system with 4 units and a 36,000 BTU heat pump unit for around $6,500 USD installed. I don't love the wall units - they're pretty ugly, even the new ones. If you're getting a mini-split, the in-ceiling or wall cassettes that are hidden are…

Wow, really? Prices seem much higher than that in Seattle. A friend got 3 handlers totaling 24k BTU for like 12 grand.

Re: Heat pumps of the 1800s are becoming the technology of the future

#308
post #266
post #199

Earlier quoted context omitted.

I don't think the hardware is that expensive in the US, it's the installation (which costs more than the hardware). And mistakes by installers will cost even more. Our installers didn't flare a line set connection properly and it leaked slowly and that was a very expensive bill (especially since refrigerants have changed so much). Our Daikin indoor units have also had condensate leaking issues, probably due to poor i…

I love our Daikin mini-splits (came with the house), but as you allude to I've had to become an mini expert on deep cleaning them. They've can get GROSS with mold when used for cooling, and the cursory filter only does so much. That being said, now they stay clean for a few years after a deep cleaning -- though my first few attempt before I refined the process did not stay clean nearly as long. (Proper water pressure…

We also had a drainage problem after ours were installed. We were very fortunate that another, more experienced tech from the same company came by to follow up on a different issue and took it on themselves to inspect the drain line. It would have leaked into our wall for a long time before it became apparent something was wrong. These units (ours are also Daikin) are a dream to operate but you definitely need to triple-check the drainage on first run.

Re: Heat pumps of the 1800s are becoming the technology of the future

#309
post #277

Earlier quoted context omitted.

Because it smells bad inside? Because fresh air feels good? Not to be snarky, but how did you miss these use cases?

If it's pretty cold outside, then you're throwing all of the ostensible energy savings of a heat pump out the window the minute you open it to air out the house. Following the thread of conversation, it just didn't compute to me: >>>> Heat pumps are great for climate control >>> Yeah, ducts are dead >> What if you want to recirculate air in your house through your central air filter to eliminate smells? > Just open t…

I think there's a middle ground.

We've just today had our first snow of the season here in a lower elevation of the Sierra Foothills. It's been chilly for 3 months or so, and our heating is an 'old school' ducted propane furnace. In time, we'll replace it with a heat pump, but not this year. Anyway, we're sensitive to accumulated odors that go with a well insulated, closed-up home in winter.

Every evening, we open three doors in the house to the outside. This is after the furnace has entered its timed 'off for the night' state. We exchange pretty much all of our air for fresh ambient, which is great when we wake up in the morning.

The impact from doing this on our propane bill is undetectable. This is because air, even humid air, has a trivial heat capacity compared to the warm house structure and contents. Those are by far the greatest energy reservoir in our home. Very little energy is lost in a daily air exchange with the ambient.

*edited for typo

Re: Heat pumps of the 1800s are becoming the technology of the future

#310
post #25

Earlier quoted context omitted.

I feel a combination with a wood burning stove is best. Especially with the potential for power cuts.

Wood pellet stoves are very efficient and semi-automated. Pellets can be cheaper than split logs (if you have to buy them).

They need a generator when the power goes out though.
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