Head Range

Sorry for the ultra-noob question but I'm trying to determine the head range of my system so I can view the GPM on the pump curve (for my grundfos ups15-58frc pump). I saw formula which is (feet of pipe x 1.5 x .04) but I don't trust it since pipes have different diameters.

I have 80ft of 1-1/8" ID Pex tubing, 25 Gallon wood boiler, and 12.8 gallon oil furnace. Can someone show me how to calculate the head range? Thanks

Can someone check my math for me? I'm a bit confused because according to the pump curve for my pump, I should set the pump to medium speed. However, the system is working just fine at low speed. I prefer the lowest speed possible so the wood boiler won't have to work hard to heat the water.

Based on the link posted above, here are my results plus the pump curve below:

Target Flow:
90,000btu / (500x20) = 9GPM

Length of Piping Circuit:
80FT Straight Pipe
90deg Elbows: 9 x 2.82ft
45deg Elbows: 2x 1.60ft
Tees: 2x 6.90ft
Flow Check: 48ft
Ball Valves: 2x 6.80ft

=184ft

Head Loss:
0.000794 (1-1/4" PEX) x 0.933 (correction for water @ 180deg) x 184ft (length of circuit) x 46.765 (9GPM raised to 1.75 power)

=6.374ft


Summary: Flow = 9GPM & Feet of Head = 6.374ft

Like I said earlier, based on these numbers I should have the pump set on speed #2 but I've been running on speed one for about 1 week now.

My temperature drop with all zones running plus the shower running in 20-25 degree outside temps is about 20 degrees. With one zone running the temp drop is only 5-7 degrees max.

I also don't have any of the interior pex tubing insulated yet and only half of the pex in the garage is insulated. My wood boiler is located in the attached garage, about 30ft away from the oil boiler.

Harman SF-160 wood boiler. I'm very pleased with it although it doesn't last longer than 6-7 hours so I wish I got the larger model (SF-260). My father has the SF-360 on a house twice the size as mine and his will go 8-9 hours if the t-stats are turned down to 60deg at night. It's no big problem for me but in the middle of the night when I get up to have a snack or use the bathroom I now have to go out to the garage and load up the boiler. Otherwise if I sleep past 7 hours the boiler runs out of wood.

As far as meeting the heating demands, it works perfectly and I have no complaints.

I highly dislike Harman's install instructions and Johnson Controls that they send you. I like Johnson Control systems a lot but the controls Harman sends you are not capable of hooking their boiler to an oil boiler even though the instructions say you can. They are also no help over the phone when confronted about this. They send you Johnson Controls System 350 controls which are fine for running the boiler as a standalone unit but you need System 450 controls or some other type (e.g. Taco Aquastats) to properly connect the boiler to an existing oil boiler. I can explain this more in detail if you want to message me.