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

knowablemagazine.org

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

#231

Post by twawaaay »

I am in constant bewilderment about all of the talk of saving electricity but still so few homes having a very basic device like heat exchanger.

At its very simplest it is just a box where incoming air is being heated by outgoing air without both getting mixed. It is a bunch of pipes, radiators and two fans in a box.

Whether you heat or cool your house, an open window is energy loss. The heat exchanger lets you keep your house nicely ventilated while reducing those losses due to ventilation by something like 90%.

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

#232

Post by IAmGraydon »

fifteenforty wrote: post #109

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 really the way to go IMO.

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

#233

Post by siod »

lll-o-lll wrote: post #192
phyzome wrote: post #144

> owners of drafty homes may need to take on the added cost of insulation when installing a heat pump Installing good insulation is also really important even if you're not using heat pumps! With bad insulation, you're wasting energy no matter what technology you're using.

If you live in a warm climate, I personally think insulation is the worst (excepting roofing). Not because of efficiency, but because you isolate yourself from nature! The traditional Queenslander (look up Bluey if you don’t know what I mean), has so much going for it. It allows airflow through the whole house, a protected outside to sit and be with nature, lizards coming and going, bliss! This hermetically sealed en…

The Queenslander house style was built for large blocks that had sufficient airflow, they were built to be cheap and don't work properly with modern block sizes. While they are iconic, and have some great design features, the lack of insulation is not one of them. A modern well insulated house with a heatpump + solar is extremely energy efficient and comfortable in all weather.

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

#234

Post by jopsen »

nickpeterson wrote: post #4

Why can’t my whole home participate in this technology? It would seem an ok fit for things like freezers, refrigerators, hot water heaters, etc. When it’s freezing cold outside, it seems crazy that I warm the air of my house and then use electricity to keep the fridge cooler than the air I just heated. Someone needs to make a standard for moving heat/cool through all appliances in a house…

> When it’s freezing cold outside, it seems crazy that I warm the air of my house and then use electricity to keep the fridge cooler

Installing ducts, etc. might take more energy than is consumed over the product life-cycle.

It would add other limitations, such as only being able to put fridges next to exterior wall.

Or most likely it'll add additional installation cost. Money perhaps better spent insulating your house better.

You'd have fewer compatible vendors to choose from. Less competition.

Flexibility is probably way more important than micro optimizations.

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

#235

Post by fifteenforty »

thehappypm wrote: post #228
Brybry wrote: 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…

Daikon is way worse than Mitsubishi from what my hvac guy tells me

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.

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

#236

Post by fifteenforty »

IAmGraydon wrote: post #232
fifteenforty wrote: post #109

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…

Can you give me an example of a comparable model available in the US?

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

#237

Post by Tade0 »

darknavi wrote: post #203
lll-o-lll wrote: post #192

Earlier quoted context omitted.

If you live in a warm climate, I personally think insulation is the worst (excepting roofing). Not because of efficiency, but because you isolate yourself from nature! The traditional Queenslander (look up Bluey if you don’t know what I mean), has so much going for it. It allows airflow through the whole house, a protected outside to sit and be with nature, lizards coming and going, bliss! This hermetically sealed en…

That can work just fine by intentionally opening windows. Having a "drafty" house is just forcing that 100% of the time (which isn't always wanted). Side note: As a US resident in an area with a ton of mosquitos, I cannot understand why other countries don't heavily use window screens. Lizards a pretty cool, flies and other flying bugs are just annoying and gross.

In Europe, outside of the south, mosquitoes are pretty tame.

After spending some years in Italy I developed a partial immunity to mosquito bites. It lasted for about half a year.

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

#238

Post by jimmaswell »

fifteenforty wrote: post #159
jimmaswell wrote: post #151

Earlier quoted context omitted.

> Ducts are dead. How do you move the heated/cooled air into/around the house without ducts?

It’s a ‘mini split’ in US lingo. There are thin, highly insulated refrigerant lines going between the outside unit and the inside unit. The inside unit exchanges heat with the air. https://www.daikin.com.au/our-product-range/split-system-air...

That thing's an eyesore compared to a duct to me.

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

#239

Post by klyrs »

PinguTS wrote: post #49

Sorry, but I don't see any novelty here. Everything described in the article is commercially available. At least here in Germany. Heat pumps are used to heat a storage container called buffer, a water container of 200l or more of water. This is used to run the heat pump when energy is cheap to warm up the buffer. That is for example in daytime when energy is available from the photovoltaic. If you don't have photovol…

> Sorry, but I don't see any novelty here

Some irony on a story with the title "Heat pumps of the 1800s..."

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

#240

Post by HellzStormer »

twawaaay wrote: post #231

I am in constant bewilderment about all of the talk of saving electricity but still so few homes having a very basic device like heat exchanger. At its very simplest it is just a box where incoming air is being heated by outgoing air without both getting mixed. It is a bunch of pipes, radiators and two fans in a box. Whether you heat or cool your house, an open window is energy loss. The heat exchanger lets you keep…

Logically (and ideally), the incoming air and outgoing air would exchange heat until they are at the same temp, which would be in the middle. So I would not expect an efficiency higher than 50% unless there is some special tech I'm not aware?
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