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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

#261

Post by catiopatio »

kccqzy wrote: post #204
mvnuweucxqokii wrote: post #163

Earlier quoted context omitted.

Not to be snarky, but if the weather outdoors is uncomfortable enough to be using climate control, why would I want to open the window?

Because presumably in this case you would want to open a window for fresh air, and simultaneously run your heating system to heat up that fresh air? I was responding to a comment that presupposes the need for fresh air. If you don't need that, feel free to close the windows then.

You do realize that “open the window and hear that air” is massively energy inefficient, right?

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

#262

Post by fifteenforty »

Brybry wrote: post #199
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…

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 take your point, but installation faults in central gas heating are also very common, but perhaps less obvious. The main one I’m thinking about is poor sealing or placement of the return duct, causing entrainment of air from the wall cavity. Source: local experts, and then I inspected my friend’s houses (hah).

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

#263

Post by dahfizz »

AOsborn wrote: post #249
teruakohatu wrote: post #110

Earlier quoted context omitted.

> Ducts are dead. Ducted heatpumps are a thing here in NZ and make sense to me, not that I have used one. The heatpump sits in the roof and air is pushed into three or so rooms through ducts. If building a new house I think ducts would be the way to go.

I thought this was absolutely the solution but backtracking a little now based on experience so far. We have a two-level, five bedroom new build in Auckland which came with a single-zone ducted system. So outputs are the bedrooms plus upstairs and downstairs lounges. The vents are tidy and unobtrusive - much less space than a wall unit in each location. We're having major issues balancing the temperature across the d…

I had a similar problem, but I decided that simply running the fan to mix up the air was a fine solution. The fan doesn't use much electricity, and it's good not to let rooms get too stale anyway.

I have the fan programmed to run 10 or 15 minutes an hour regardless of if the heat pump needs to run. It keeps things pretty even.

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

#264

Post by briHass »

Scoundreller wrote: post #98
rpearl wrote: post #17

Earlier quoted context omitted.

There are heat pump water heaters (I have one; AO Smith HPTU-50N). More expensive up front vs tankless but a lot more efficient.

Depends on usage. Tankless efficiency really shines with irregular use. Keeping a big reservoir warm for the sake of keeping it warm only becomes efficient with regular usage.

This is one of the bigger myths used to sell tankless. Modern water heater tanks are well insulated; losses are usually quoted as less than 10%.

From a cost perspective, the slight efficiency increase of tankless never pays back over the cost of the unit, and unfortunately, usually the more frequent repairs. The big benefit is the 'unlimited' hot water.

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

#265

Post by throwawaylinux »

TheSpiceIsLife wrote: post #223
kccqzy wrote: post #204

Earlier quoted context omitted.

Because presumably in this case you would want to open a window for fresh air, and simultaneously run your heating system to heat up that fresh air? I was responding to a comment that presupposes the need for fresh air. If you don't need that, feel free to close the windows then.

Airborne allergens can be an issue, and dust more generally.

Seems like it would be more efficient to wear a climate controlled bubble suit than heating up entire rooms. And you could even go outside when it is cold or hot or dusty.

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

#266

Post by darken »

Brybry wrote: post #199
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…

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 and disinfect is key.)

Cleaning basically involves a dedicated cover + drain that diverts water to a bucket, and blasting it with what's effectively a "low power pressure washer" I can use indoors (carefully), and "Lemocide" to properly disinfect... And coil cleaner for the fins. Takes me a good 4+ hours per unit, largely spent preparing the area in case there is any rogue spray. (Though TBH I may be a bit obsessive about getting it right.)

I also had a drain leak as you mentioned -- blasting the drain line with aforementioned "low pressure washer" helped with that. Still a bit gross to deal with. (And learning how to properly disassemble and clean the drip tray is the final thing I've put off leaning for a completely-thorough deep clean... I'm a bit horrified anticipating what I'll find...)

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

#267

Post by throwawaylinux »

AOsborn wrote: post #249
teruakohatu wrote: post #110

Earlier quoted context omitted.

> Ducts are dead. Ducted heatpumps are a thing here in NZ and make sense to me, not that I have used one. The heatpump sits in the roof and air is pushed into three or so rooms through ducts. If building a new house I think ducts would be the way to go.

I thought this was absolutely the solution but backtracking a little now based on experience so far. We have a two-level, five bedroom new build in Auckland which came with a single-zone ducted system. So outputs are the bedrooms plus upstairs and downstairs lounges. The vents are tidy and unobtrusive - much less space than a wall unit in each location. We're having major issues balancing the temperature across the d…

Can't you choke down the airflow from your bedroom duct?

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

#268

Post by catiopatio »

batiudrami wrote: post #258
jimmaswell wrote: post #238

Earlier quoted context omitted.

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

Much like solar panels on the roof (which I have also heard Americans describe as an eyesore), once they are common enough your eyes just slide over them and you don’t notice.

I don’t see rooftop solar panels unless I go outside and intentionally look for them.

A mini-split system puts an ugly, cheap, plastic wall-cyst within your field of view in every room they’re installed.

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

#269

Post by fifteenforty »

darken wrote: post #266
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…

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…

The no 1 reason I bought the Daikin model referenced over the comparable Mitsubishi Electric is that it has the ‘MOULD PROOF’ function. It runs the fan automatically after you have had it in cooling mode, to evaporate the moisture build up from the interior condenser coil, thereby removing the moisture required for the growth of bacteria and mould.

So far, it seems to be working! Better than relying on everyone to manually do it (literally this is the instruction in the Mitsubishi Electric user manual).

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

#270

Post by teruakohatu »

thehappypm wrote: post #248
teruakohatu wrote: post #114

Earlier quoted context omitted.

I hadn't considered that. My argument with split systems, at least how they are installed in NZ, is that they are usually installed in the main living area and if there is a second unit, in a corridor. So corridors are heated or cooled far hotter or colder than they need to be in order to heat/cool bedrooms.

I have two units that are heated by heat pumps in Massachusetts. One has mini splits. You definitely don’t generally put mini splits in every single room (like bathrooms or interior hallways) because each mini split requires tubing, is large, and expensive. No, I think it’s way more likely that you would have them in the bedrooms rather than the hallway

In New Zealand I have seen small heatpumps in bedrooms, but I would have to say it is extremely rare.

But we have many very toasty hallways leading to cold single glazed bedrooms!

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