Drew Wathey
New Member
Hello everyone,
I'm looking to install a submersible well pump in my cistern and I'm trying to figure out the total dynamic head to properly spec a pump. The issue I'm running into is I don't know how to calculate it for a PEX system that uses manifolds.
I'm aiming for an overall flow rate of 22 GPM and a constant pressure of 40-50 psi, which I'll be using a CSV to accomplish.
Here are is the piping setup:
Elevation difference: 7 feet
Main Run
32 mm X 30 foot horizontal run from pump to CSV
32 mm X 6 foot from CSV to cold and hot main distribution manifold
20 mm X 12 foot to washing machine (1 tee + 1 right angle)
20 mm X 19 foot to sink (1 right angle)
Run 1 Cold
25 mm X 190 foot to manifold in bathroom (2 right angle fittings)
20 mm X 1 foot to sink
20 mm X 5 foot to toilet (1 right angle fittings)
20 mm X 12 foot to shower (2 right angle fittings)
20 mm X 12 foot to outside spigot
Run 2 Cold
25 mm X 125 foot to manifold in bathroom 2 (1 right angle)
20 mm X 1 foot to sink (1 right angle)
20 mm X 5.5 foot to toilet (1 right angle)
20 mm X 13 foot to shower (2 right angles)
Run 3 Cold
25 mm X 17 foot to manifold in bathroom 3 (1 right angle)
20 mm X 1 foot sink
20 mm X 4 foot to toilet (1 right angle)
20 mm X 10 foot to shower (2 right angles)
Run 4 Cold
25 mm X 33 foot run to manifold in kitchen
20 mm X 1 foot to sink
20 mm X 4 foot to dishwasher (1 right angle)
20 mm X 16 foot refrigerator (3 right angles)
20 mm X 42 foot to shower (3 right angles)
The above information is only for cold runs. I'm no sure if I need to include the hot runs to determine total dynamic head.
I'm looking to install a submersible well pump in my cistern and I'm trying to figure out the total dynamic head to properly spec a pump. The issue I'm running into is I don't know how to calculate it for a PEX system that uses manifolds.
I'm aiming for an overall flow rate of 22 GPM and a constant pressure of 40-50 psi, which I'll be using a CSV to accomplish.
Here are is the piping setup:
Elevation difference: 7 feet
Main Run
32 mm X 30 foot horizontal run from pump to CSV
32 mm X 6 foot from CSV to cold and hot main distribution manifold
20 mm X 12 foot to washing machine (1 tee + 1 right angle)
20 mm X 19 foot to sink (1 right angle)
Run 1 Cold
25 mm X 190 foot to manifold in bathroom (2 right angle fittings)
20 mm X 1 foot to sink
20 mm X 5 foot to toilet (1 right angle fittings)
20 mm X 12 foot to shower (2 right angle fittings)
20 mm X 12 foot to outside spigot
Run 2 Cold
25 mm X 125 foot to manifold in bathroom 2 (1 right angle)
20 mm X 1 foot to sink (1 right angle)
20 mm X 5.5 foot to toilet (1 right angle)
20 mm X 13 foot to shower (2 right angles)
Run 3 Cold
25 mm X 17 foot to manifold in bathroom 3 (1 right angle)
20 mm X 1 foot sink
20 mm X 4 foot to toilet (1 right angle)
20 mm X 10 foot to shower (2 right angles)
Run 4 Cold
25 mm X 33 foot run to manifold in kitchen
20 mm X 1 foot to sink
20 mm X 4 foot to dishwasher (1 right angle)
20 mm X 16 foot refrigerator (3 right angles)
20 mm X 42 foot to shower (3 right angles)
The above information is only for cold runs. I'm no sure if I need to include the hot runs to determine total dynamic head.