A 35 GPM McDonald will work fine. But it will still only pump about 30 GPM at that head and more like 28 GPM through a CSV1A as it is really only rated for up to 25 GPM.
Need a verdict on where to go next on pump tripping overload
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A 35 GPM McDonald will work fine. But it will still only pump about 30 GPM at that head and more like 28 GPM through a CSV1A as it is really only rated for up to 25 GPM.
The confusion I still seem to be having is what is the difference going from a 35 GPM 2 HP (AYM24200) to a 35 GPM 3 HP (AYM24300) especially with a CSV1a system?
Looking at the efficiency curves and my water head, both seems overkill? Although the pump is 64' down, they are using 175' as TDH (total dead head) in the calculation and friction loss simulation to recommend the pump. The reason for 175' is that I told them the pump is about 110'-120' from where it enters the house (the sprinkler is tee off there too just before it enters the house). Is this all making sense and correct or am I out the ballpark creating an overkill system that will require bigger parts all around?
Even using this calculator: It seems even a 1 HP pump should work? What gives?
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The 50 PSI you need is the same as the pump lifting 115'. Add that to the actual depth of the water (75') and you get 190' total head. Trying to squirt 30 GPM through a CSV1A made for 25 GPM or less will add another 69' of head for a total of 259' of head. At 259' of head that 2HP will deliver about 24 GPM while the 3HP will do about 35 GPM. If you want to go with these larger pumps, a larger CSV will reduce the friction loss and give you more GPM, and a larger tank is needed to reduce the cycles as larger pumps can handle fewer cycles.
From 50' of lift plus 50 PSI that pump should deliver about 22 GPM. That will work fine.
Great, you had mention earlier about the wire you like to use. Do you know where to find a good supply of it?
Also, the pump has a recommended range of 8-33 GPM depending on model in the 25GS range. How to accommodate for less than 8 GPM usage (normal household usage) especially with a CSV1A?
Also, the pump has a recommended range of 8-33 GPM depending on model in the 25GS range. How to accommodate for less than 8 GPM usage (normal household usage) especially with a CSV1A?
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That pump will work fine down to as little as 2/10's of a gpm flow. The CSV will have a minimum of 1 GPM, which is 5 times more than needed to keep the pump cool.
THHN wire can be gotten at many locations, including home cheapo.
It looks like this.
It looks like this.
Found some here.
https://www.wireandcableyourway.com/12-4c-thhn-pvc-tray-cable.html
https://www.wireandcableyourway.com/12-4c-thhn-pvc-tray-cable.html
Thank you.
Forgive me, I'm still struggling and trying to answer to the question of why on these Goulds (with CentriPro motors) it has these high recommended minimum GPM with lower than 3 HP motors and those pumps with Franklin motors seems to not have any until 3 HP and above?
Nobody publishes a real minimum safe flow for their pumps. They will work safely at much lower flow rates than you would expect. I had to do the testing myself about 25 years ago because I could not get an answer. Floating stack impeller designs like Goulds have very little friction in the pump end, and need very little water flow to stay cool. As long as the motor amps are decreased when the flow is restricted, the motor has been de-rated enough that it could safely pump hot water, so again it takes very little cool water to operate safely.
Again the bare minimum flow for a 2HP or smaller is 2/10's of a GPM. This is why the minimum built into the CSV is 1 GPM, which is 5 times more flow than needed to keep the pump cool. 3HP and 5 HP motors can stay cool down to about 1 GPM, which is why there is a 3-5 GPM minimum on those sizes of CSV's.
Pump manufacturers don't want you to know the minimum cooling flows are so low for normal pumps. That is because the VFD's they are trying to sell you do not de-rate the motor and still requires a full 0.5 feet per second flow to cool the motor. They just don't want you to know that a CSV is much better for the pump and can safely work at lower flow rates than VFD's.
Again the bare minimum flow for a 2HP or smaller is 2/10's of a GPM. This is why the minimum built into the CSV is 1 GPM, which is 5 times more flow than needed to keep the pump cool. 3HP and 5 HP motors can stay cool down to about 1 GPM, which is why there is a 3-5 GPM minimum on those sizes of CSV's.
Pump manufacturers don't want you to know the minimum cooling flows are so low for normal pumps. That is because the VFD's they are trying to sell you do not de-rate the motor and still requires a full 0.5 feet per second flow to cool the motor. They just don't want you to know that a CSV is much better for the pump and can safely work at lower flow rates than VFD's.
Do you usually do 12 gauge vs. 10 gauge?
With a 2HP #12 is good to 250' and #10 is good to 390'.
With a 3HP #12 is good to 190' and #10 is good to 300'.
With a 3HP #12 is good to 190' and #10 is good to 300'.
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