Viessmann Vitodens 200-W B2HA series, Application Manual

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70
Application Rules & Formulas
Universal Hydronics Formula:
GPM=
BTUH
500 x ∆T
BTUH= GPM x 500 x ∆T
Quick Pipe Resistance Calculation:
1. Measure longest run of pipe
2. Add 50% for fittings
3. Multiply by .04
= A rough calculation on the feet of
head the pump needs to overcome
for that circuit.
Piping & Tubing Properties
Steel/Wrought Iron Pipe
Pex Tubing
Copper Tubing (Type L)
*Based on a velocity of 4fpm
*Based on 20°F ∆T
*Based on a velocity of 4fpm
*Based on 20°F ∆T
*Based on a velocity of 4fpm
*Based on 20°F ∆T
Size
Content/ft
(gal)
Max Flow Rate
1
(GPM)
Max Heat Carrying
Capability (BTUH)
2
1/2" .016 4 40,000
3/4" .028 7 70,000
1" .045 12 120,000
1-1/4" .078 20 200,000
1-1/2" .106 28 280,000
2" .174 44 440,000
Size
Content/ft
(gal)
Max Flow Rate
1
(GPM)
Max Heat Carrying
Capability (BTUH)
2
1/2" .009 2.3 23,000
5/8" .013 3.3 33,000
3/4" .018 4.6 46,000
1" .030 7.5 75,000
1-1/4" .046 11.2 112,000
1-1/2" .105 15.6 156,000
Size
Content/ft
(gal)
Max Flow Rate 1
(GPM)
Max Heat Carrying
Capability (BTUH)
2
3/8" .007 2 20,000
1/2" .012 3.2 32,000
3/4" .025 6.5 65,000
1" .043 10.9 109,000
1-1/4" .065 16.3 163,000
1-1/2" .092 22.9 229,000
2" .161 39.6 396,000