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Slightly OT, but.. I live in a temperate climate. I've sometimes wondered if it would be worthwhile to adjust house construction so that: - In the summer, the

Slightly OT, but.. I live in a temperate climate. I've sometimes wondered if it would be worthwhile to adjust house construction so that: - In the summer, the kitchen refrigerator's heating coils touch outdoors air instead of indoors air. - In the winter, the refrigerator's cooling is provided, at least partially, by the outside air. - In the summer (only), the kitchen oven vents into the outdoors rather than into the kitchen. - In the winter (only), a heat exchanger recovers some of the heat from our electric clothes dryer.

MrStonedOne 8y ago
One idea i've had is to just make a central heatpump system. Why does a fridge need its own compressor that vents heat back to the house even in the summer? Why can't your water heater use that same heat instead? This all started because my brother used to redirect dryer air back into his apartment during the winter, using a saw dust sock to keep the lint contained. I started thinking about how heat could be better managed if everything used a central ac/heat pump. heat generated by the fridge, your computer, the ac, etc could be used by your water heater, your heater heater, your dryer. Add heat recovery systems to your dryer, and your drains, and bam super sustainability.
- throw0101a 8y ago
  There are AC units that do this: pipe the heat to the hot water tank first. * https://www.rheem.com/innovations/innovation_residential/integrated_systems/ https://www.rheem.com/innovations/innovation_residential/int... * https://techcrunch.com/2011/06/12/air-conditioning-water-heater/ https://techcrunch.com/2011/06/12/air-conditioning-water-hea... Once the water tank reaches its max temperature, then heat is dumped outside. The practical problem is that you need to have the different parts work together, and fridge makers don't don't to hot water makers.
  - henrikschroder 8y ago
    In the apartment I live in now in Hawaii, the utility closet has the AC unit mounted right above the water heater. They are not connected at all. And this is in a building that is about ten years old. I have no words, it's so fucking stupid.
  - MrStonedOne 8y ago
    >The practical problem is that you need to have the different parts work together, and fridge makers don't don't to hot water makers. You don't need a fridge or a hot water heater or an ac or a furnace at that point, because the primary function has been offloaded to the central heat pump. you need heat exchanger attached to water, heat exchangers attached to a cold room, heat exchangers attached to a central air system. You don't have to have the parts work together if the most expensive part of each appliance has been centralized. At that point you've now reduced the appliance to where to put the heat exchanger.
throw0101a 8y ago
There are AC units that, instead of sending heat to the outdoor device, pipe it to the hot water heater. There are also hot water heaters that, instead of burning something to heat water, have an heat exchanger on top of them to extract the warm from the surrounding air. Usually called "hybrid". I known Rheem makes such units, but there may be others.
- Scoundreller 8y ago
  You’d think any A/C tech could loop around the outgoing AC pipe to the cold water intake, and insulate it. It won’t be anywhere near 100%, but the extra $50 in copper pipe could pay for itself.
bzbarsky 8y ago
Recovering heat from a dryer is not trivial: the output air from a dryer has a bunch of lint in it (yes, even with the lint filter in there!), so either your heat exchanger or the filter in front of it or both will get clogged pretty regularly.
- Yetanfou 8y ago
  There are several electric tumble dryers which use a heat pump to recover heat: https://en.wikipedia.org/wiki/Clothes_dryer#Heat_pump_dryers https://en.wikipedia.org/wiki/Clothes_dryer#Heat_pump_dryers
  - Scoundreller 8y ago
    Which also don’t require a vent. I just hang my clothes and let the evaporating water cool the place a bit.

MrStonedOne 8y ago

One idea i've had is to just make a central heatpump system. Why does a fridge need its own compressor that vents heat back to the house even in the summer? Why can't your water heater use that same heat instead? This all started because my brother used to redirect dryer air back into his apartment during the winter, using a saw dust sock to keep the lint contained. I started thinking about how heat could be better managed if everything used a central ac/heat pump. heat generated by the fridge, your computer, the ac, etc could be used by your water heater, your heater heater, your dryer. Add heat recovery systems to your dryer, and your drains, and bam super sustainability.

throw0101a 8y ago
There are AC units that do this: pipe the heat to the hot water tank first. * https://www.rheem.com/innovations/innovation_residential/integrated_systems/ https://www.rheem.com/innovations/innovation_residential/int... * https://techcrunch.com/2011/06/12/air-conditioning-water-heater/ https://techcrunch.com/2011/06/12/air-conditioning-water-hea... Once the water tank reaches its max temperature, then heat is dumped outside. The practical problem is that you need to have the different parts work together, and fridge makers don't don't to hot water makers.
- henrikschroder 8y ago
  In the apartment I live in now in Hawaii, the utility closet has the AC unit mounted right above the water heater. They are not connected at all. And this is in a building that is about ten years old. I have no words, it's so fucking stupid.
- MrStonedOne 8y ago
  >The practical problem is that you need to have the different parts work together, and fridge makers don't don't to hot water makers. You don't need a fridge or a hot water heater or an ac or a furnace at that point, because the primary function has been offloaded to the central heat pump. you need heat exchanger attached to water, heat exchangers attached to a cold room, heat exchangers attached to a central air system. You don't have to have the parts work together if the most expensive part of each appliance has been centralized. At that point you've now reduced the appliance to where to put the heat exchanger.

throw0101a 8y ago

There are AC units that, instead of sending heat to the outdoor device, pipe it to the hot water heater. There are also hot water heaters that, instead of burning something to heat water, have an heat exchanger on top of them to extract the warm from the surrounding air. Usually called "hybrid". I known Rheem makes such units, but there may be others.

Scoundreller 8y ago
You’d think any A/C tech could loop around the outgoing AC pipe to the cold water intake, and insulate it. It won’t be anywhere near 100%, but the extra $50 in copper pipe could pay for itself.

bzbarsky 8y ago

Recovering heat from a dryer is not trivial: the output air from a dryer has a bunch of lint in it (yes, even with the lint filter in there!), so either your heat exchanger or the filter in front of it or both will get clogged pretty regularly.

Yetanfou 8y ago
There are several electric tumble dryers which use a heat pump to recover heat: https://en.wikipedia.org/wiki/Clothes_dryer#Heat_pump_dryers https://en.wikipedia.org/wiki/Clothes_dryer#Heat_pump_dryers
- Scoundreller 8y ago
  Which also don’t require a vent. I just hang my clothes and let the evaporating water cool the place a bit.