This article explores the new macro designer and other new macro features available in Access 2010. After reading this article, you will be able to take full advantage of what Access 2010 macros have to offer.
Rules For Sizing Your Heat Pump Pool Heater. 1  Size at 4 BTUâs per gallon or 1 BTU per litre of water. To heat in normal summer conditions when ambient air temperature average 70Â°F in a 24 hour period.  Size at 5 BTUâs per gallon or 1.3 to 1.5 BTUâs per litre of water.
At 92% efficiency, that's 14,126 BTU. From above, heating a gallon of water by 1Â°F takes 8.33 BTU. Heating from 68Â°F to 104Â°F would by a 36Â°F rise, or 36 x 8.33 = 300 BTU to heat 1 gallon of water. With 14,126 BTU, we could heat 14,126 BTU Ã· 300 BTU/gallon = 47 gallons. So, our typical 4500-watt electric heater can make 47 gallons of hot water per hour â about a full tank.