Primary Loop Equivalent Length Calculations & Pump Selection - UTICA BOILERS OLSSV-050 Installation, Operation & Maintenance Manual

50/75/100 MBH - PRIMARY LOOP EQUIVALENT LENGTH CALCULATION & PUMP SELECTION
These charts are valid for piping diagrams on pages 17 & 18
Instructions:
1.
Pipe diameter determines pump size. Smaller the diameter of pipe, larger the pump. 50/75/100 Mbh boilers can be
piped in 3/4" , 1" or 1¼" pipe. Use charts 1-4 to determine pipe size and respective pump size.
2. Fill in chart using the 3/4" section first. Then consult chart 4 for pump selection.
3.
Pump size may be decreased by decreasing equivalent length of pipe. Use larger diameter pipe as primary loop to
decrease equivalent length. Use chart 2 or 3.
Note: The figures below are based on industry average. Consult valve/fitting manufaturer for exact equivalent length or
for fittings not shown below.
Chart 1
Pipe Diameter
3/4"
Chart 2
Pipe Diameter
1"
For 50/75/100 MBH Boilers
(This boiler must be piped with a primary loop)
Fitting
90° Elbow
45° Elbow
Tee-branch
Tee-through
Swing check valve
Lift check valve
Fitting
90° Elbow
45° Elbow
Tee-branch
Tee-through
Swing check valve
Lift check valve
A
Enter Number Of
Fittings
Enter Total 3/4" straight pipe length in feet
Add up numbers in column C
Total equivalent length of Primary
A
Enter Number of
Fittings
Enter Total 1" straight pipe length in feet
Add up numbers in column C
Total equivalent length of Primary
Multiply Total of Column C in Chart 2 by 0.26
84
B
Equivalent Length
Multiply By
1.875
1
3.75
1.25
6.25
37.5
Pump Factor
B
Equivalent Length
Multiply By
1.875
1
3.75
1.25
6.25
37.5
Pump Factor
P/N# 2400010616, Rev. F [10/26/2015]
C
A x B
C
A x B