20 pages

Tankless Water Heater Sizing by Fixtures and Inlet Temperature

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Tankless Water Heater Sizing by Fixtures and Inlet Temperature: 20 pages. A tankless unit is sized by flow and temperature rise together. These pages pair every realistic fixture count with every realistic inlet temperature and give the input each combination actually requires.

1 fixture, 40 F inlet Running 1 fixture at once needs 2 gallons per minute, and at a 40 F inlet reaching 120 F is a 80 F rise, which takes about 98,000
1 fixture, 50 F inlet Running 1 fixture at once needs 2 gallons per minute, and at a 50 F inlet reaching 120 F is a 70 F rise, which takes about 85,000
1 fixture, 60 F inlet Running 1 fixture at once needs 2 gallons per minute, and at a 60 F inlet reaching 120 F is a 60 F rise, which takes about 73,000
1 fixture, 70 F inlet Running 1 fixture at once needs 2 gallons per minute, and at a 70 F inlet reaching 120 F is a 50 F rise, which takes about 61,000
1 fixture, 75 F inlet Running 1 fixture at once needs 2 gallons per minute, and at a 75 F inlet reaching 120 F is a 45 F rise, which takes about 55,000
2 fixture, 40 F inlet Running 2 fixtures at once needs 4 gallons per minute, and at a 40 F inlet reaching 120 F is a 80 F rise, which takes about 195,00
2 fixture, 50 F inlet Running 2 fixtures at once needs 4 gallons per minute, and at a 50 F inlet reaching 120 F is a 70 F rise, which takes about 171,00
2 fixture, 60 F inlet Running 2 fixtures at once needs 4 gallons per minute, and at a 60 F inlet reaching 120 F is a 60 F rise, which takes about 146,00
2 fixture, 70 F inlet Running 2 fixtures at once needs 4 gallons per minute, and at a 70 F inlet reaching 120 F is a 50 F rise, which takes about 122,00
2 fixture, 75 F inlet Running 2 fixtures at once needs 4 gallons per minute, and at a 75 F inlet reaching 120 F is a 45 F rise, which takes about 110,00
3 fixture, 40 F inlet Running 3 fixtures at once needs 6 gallons per minute, and at a 40 F inlet reaching 120 F is a 80 F rise, which takes about 293,00
3 fixture, 50 F inlet Running 3 fixtures at once needs 6 gallons per minute, and at a 50 F inlet reaching 120 F is a 70 F rise, which takes about 256,00
3 fixture, 60 F inlet Running 3 fixtures at once needs 6 gallons per minute, and at a 60 F inlet reaching 120 F is a 60 F rise, which takes about 219,00
3 fixture, 70 F inlet Running 3 fixtures at once needs 6 gallons per minute, and at a 70 F inlet reaching 120 F is a 50 F rise, which takes about 183,00
3 fixture, 75 F inlet Running 3 fixtures at once needs 6 gallons per minute, and at a 75 F inlet reaching 120 F is a 45 F rise, which takes about 165,00
4 fixture, 40 F inlet Running 4 fixtures at once needs 8 gallons per minute, and at a 40 F inlet reaching 120 F is a 80 F rise, which takes about 390,00
4 fixture, 50 F inlet Running 4 fixtures at once needs 8 gallons per minute, and at a 50 F inlet reaching 120 F is a 70 F rise, which takes about 341,00
4 fixture, 60 F inlet Running 4 fixtures at once needs 8 gallons per minute, and at a 60 F inlet reaching 120 F is a 60 F rise, which takes about 293,00
4 fixture, 70 F inlet Running 4 fixtures at once needs 8 gallons per minute, and at a 70 F inlet reaching 120 F is a 50 F rise, which takes about 244,00
4 fixture, 75 F inlet Running 4 fixtures at once needs 8 gallons per minute, and at a 75 F inlet reaching 120 F is a 45 F rise, which takes about 219,00