HVAC
HVAC guides
Guides on BTU, tons, SEER, EER, energy use and what really drives the size of a unit.
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What size air conditioner do I need?It depends on far more than square footage, but there is a starting point.BTU per square foot for air conditioning30 to 40 BTU/h per square foot, with caveats that matter.BTU, tons and kW of cooling explainedOne ton is 12,000 BTU/h. Here is everything that follows from that.What size air conditioner for 200 square feet?Around 7,000 BTU, with caveats that can move the number.What size air conditioner for 300 square feet?Around 10,000 to 12,000 BTU for a typical living room.BTU vs frigories: what is the difference?They measure the same thing on different scales: 1 frigorie is 3.97 BTU.What is SEER?Efficiency across a whole season, not at a single moment.What is EER?Cooling produced divided by electricity used, at one operating point.How much electricity does an air conditioner use?It depends on the electrical power, not on the BTU rating.How much does it cost to run an air conditioner?Power times hours times your price per kWh. Nothing more.How insulation affects air conditioner sizeBetween a well-insulated and a poorly insulated room there is a 40 % difference.How sun exposure affects air conditioner sizeAn unshaded west window can add more heat than three people.