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6 votes

Reuse waste heat from air conditioning

The problem of heating water from waste heat from air conditioning is that the water needs to be heated to at least 60 degrees Celsius to prevent Legionella bacterium from growing. On the other hand, ...
juhist's user avatar
  • 5,099
5 votes
Accepted

Should storm windows be left open in the summer to reduce hothouse heat gain?

Keeping your storm windows closed in the summer will result in net energy savings due to reduced ventilation. EDIT: model updated to eliminate cooling load during the winter. Using eQUEST, a ...
LShaver's user avatar
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5 votes
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Why refrigerant cooler is more popular than evaporative cooler?

You have to also consider the climate where each type of cooler will be used and how each type of cooler works. Refrigeration coolers transfer heat from inside a building to the outside. However, the ...
Fred's user avatar
  • 3,507
4 votes

How to benefit from air-conditioning water

You certainly can use it as water to grow plants. But better not drinking it, since it can host bacteria in the long run. There is good stuff about it here: http://www.slate.com/articles/...
J. Chomel's user avatar
  • 1,417
4 votes

How to reduce indoor humidity in the summer time?

Most folks don't know that their 'frost free fridge' can be easily hacked to act as a dehumidifier. As it runs continuously, it can be used to suck unwanted moisture out of a humid home 24 hours a ...
Tim's user avatar
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3 votes
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Is it inefficient to turn off the airconditioner for short durations of less than two hours?

I was recently recommended not to turn off the airconditioner (A/C) when leaving a room for two hours or less but instead to increase the temperature setting closer to the outside temperature. ...
juhist's user avatar
  • 5,099
3 votes

How do I keep my room on the first floor cool all day and night?

If you can't re-insulate the whole house it might be possible to insulate just your room. Since you're already using an air conditioner the lack of effective thermal mass once you do that shouldn't ...
Móż's user avatar
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3 votes

Temperature equalisation throughout the house

The story so far There are three different things that can cause an upstairs to be hotter than a downstairs, and you've mentioned each briefly in your question and comments: Convection. Hot air rises ...
LShaver's user avatar
  • 11.9k
3 votes
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What is the actual efficiency of an air to air heat pump in the winter

There's a bit of data in a paper titled A Review of Domestic Heat Pump Coefficient of Performance (by Dr Iain Staffell, Imperial College London, Centre for Environmental Policy, 2009-04) that you ...
Tim's user avatar
  • 2,844
2 votes

Would saving winter ice for summer A/C be more energy efficient?

Beer factories in Germany used ice in cellars for their production throughout the year. A/C will require far more and may even heat up the cellars, so that more ice will be needed to bring them back ...
Salt's user avatar
  • 929
2 votes

Temperature equalisation throughout the house

Enclosing the stairwell would be a big help with the heating if it can be done with your floorplan.
Derek Andrews's user avatar
2 votes
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Heat Recovery Ventilator HRV, metal vs paper core?

One expert colleague of mine had heard of this in the past. Once. So it's not unknown. Another thought that it might not be that uncommon, but that it wouldn't be wise to buy one that hadn't passed a ...
410 gone's user avatar
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2 votes
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How large should be solar panel to power air conditioner?

The two main things that need to be considered are the power requirements of the air conditioner (in kW) and the power that each type of solar panel can provide. From that you can determine how many ...
Fred's user avatar
  • 3,507
2 votes

Portable AC or Dehumidifier?

In case you are open to other ideas, a fan with a cooling system behind it can be a cheaper and effective option. Something like following image (source google) can be made with little investment. ...
vikrant's user avatar
  • 229
2 votes

How to reduce energy usage of a window air conditioner?

To reduce the effect of the 2 cm gap under the door you could attach a door sweep. Any gaps around the air conditioning unit in the window can be sealed with silicone sealant. To reduce electricity ...
Fred's user avatar
  • 3,507
2 votes

How to reduce energy usage of a window air conditioner?

Here's a few things to try: Increase the temperature setting on the Air con Air conditioning units typically do two things: lower the ambient temperature, and remove humidity from the air. Depending ...
Robotnik's user avatar
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2 votes
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For dehumidification purposes, does a ductless heat pump use more or less energy than a dehumidifier?

All else being equal, the dehumidifier will be more efficient. Both devices utilize the same refrigeration cycle (from Wikipedia): Both devices remove moisture from the air at the evaporator (3), ...
LShaver's user avatar
  • 11.9k
2 votes

Estimating real, overall efficiency of an air conditioning unit

The efficiency of an air conditioning unit is a simple division: divide heat extracted from the cold reservoir by the amount of work it takes to extract that heat. Note that an air conditioning unit ...
juhist's user avatar
  • 5,099
2 votes

How to reduce indoor humidity in the summer time?

One option is to place materials that absorb or adsorb water from the air into the house. Such materials include silica gel, clay and other mineral soils, and calcium chloride. The amount of water ...
Jean-Paul Calderone's user avatar
2 votes

Why not use condensate from a split-unit air conditioner to improve cooling efficiency?

Yes, indeed, all AC units have condensing water on the evaporator. One way to get rid of it is simply a pipe where it is discarded to a sewer or discarded outdoors. In units that are not designed to ...
juhist's user avatar
  • 5,099
2 votes

Combining fans and AC

Depending on the circumstances, using a fan when it is hot instead of air conditioning can reduce electricity consumption, but it depends on both temperature and humidity. Directing fan forced air ...
Fred's user avatar
  • 3,507
1 vote

Why is adding thermal mass good for heatwaves, given the importance of cooling off at night?

No system is ever perfect and when extreme situations occur, sometimes there aren't any good solutions. Answering your questions in reverse order. Ventilating a house over night only works when the ...
Fred's user avatar
  • 3,507
1 vote

Why is the Energy Guide efficiency rating of my air conditioner so much lower than the specification?

@jmk yes the Seasonal energy efficiency ratio or SEER a high number is better. The system won’t let me comment must be because I am new on this page of the SE . There are similar questions asked on ...
Ed Beal's user avatar
  • 131
1 vote
Accepted

Should I close vents to unused rooms?

No, closing the air vents will increase your energy bill. The added pressure from closing a vent can cause air leaks in your system, causing long-term and unnecessary energy waste. The heater or air ...
wilkvolk's user avatar
1 vote

What is the actual efficiency of an air to air heat pump in the winter

There are standards for the declared Coefficient of Performance (COP) in Europe and Canada. In Europe this is in DELEGATED REGULATION (EU) No 626/2011 (there is a more accessible discussion in ...
M Juckes's user avatar
  • 1,021
1 vote

Temperature equalisation throughout the house

Issue 1: Cold floor downstairs: Installing a few ceiling fans that kept the air near the floor moving would help a lot. Place area rugs where people's feet park helps a lot too. If the slab is ...
Sherwood Botsford's user avatar
1 vote

Temperature equalisation throughout the house

You seem to be having issues with convection taking warm air upstairs, especially if you have extractors or vents taking air from upstairs bathrooms to the outside world. I have similar issues ...
Chris H's user avatar
  • 2,126
1 vote

Mechanical damper built in to vent fan?

My high efficiency water heater has an electric damper. Conventional butterfly plate. The unit had a separate data sheet, so it wasn't part of the furnace itself. Try HVAC stores. Explain the ...
Sherwood Botsford's user avatar

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