Dunkirk Helix VX Vertical Laser Tube Wall Hung Stainless Steel Modulating Condensing Boiler - Manual (Page 84)

84
50/75/100 MBH - PRIMARY LOOP EQUIVALENT LENGTH CALCULATION & PUMP SELECTION
For 50/75/100 MBH Boilers
(This boiler must be piped with a primary loop)
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 A B C
Pipe Diameter Fitting
Enter Number Of
Fittings
Multiply By
Equivalent Length
A x B
3/4"
90° Elbow 1.875
45° Elbow 1
Tee-branch 3.75
Tee-through 1.25
Swing check valve 6.25
Lift check valve 37.5
Enter Total 3/4" straight pipe length in feet
Add up numbers in column C
Total equivalent length of Primary
Pump Factor
Chart 2 A B C
Pipe Diameter Fitting
Enter Number of
Fittings
Multiply By
Equivalent Length
A x B
1"
90° Elbow 1.875
45° Elbow 1
Tee-branch 3.75
Tee-through 1.25
Swing check valve 6.25
Lift check valve 37.5
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
Pump Factor