Maybe put a three-way valve on the line so that you can open or close the line to verify performance.
You can put a Jandy check valve on the line to give you a sight window to see where the flow begins by watching the flapper move.
I'm not clear on the placement/positioning of the valves and flowmeter:You can install a flowmeter if you want to verify the flow independently of the pump reading.
In this video, the cavitation begins at about -14" of mercury, which is about 16 feet of head, so it's possible that you could hit cavitation at full pump speed.
34 feet -16 feet = 18 feet of Net Positive Suction Head available.
The pressure required at the impeller is specific to the pump and you would need to know the Net Positive Suction Head Required for the IntelliFlo XF at full flow.
The required NPSH of a water pump at rated capacity is 17 ft.
Water Temperature 85° F. Elevation 1000 ft. above sea level.
You mentioned installing a flow meter to check the pump's output. That would be installed downstream of the Jandy CV and before the spring CV?I would do a regular 3" T (red) and then a Jandy check valve on the bypass so that you can see when the bypass begins to flow water.
You can put the Flow Meter on the line going into the heater to verify the actual flow, but you have the flow reading from the pump and the flow switch should indicate that the flow is good as long as the switch is calibrated and installed correctly.
The flowmeter is just an extra verification if you want to be extra sure.
It requires about 14" of straight PVC pipe, so you might not have that much straight pipe with everything going on.
You should be able to adjust the pump's output in GPM by slowly increasing the GPM until you see the Jandy checkvalve flapper begin to move.
For example, you can turn the pump on at 30 GPM and watch to see if the Jandy flap moves, it should not move at 30 GPM.
Then increase to 40 GPM, 45 GPM, 50 GPM etc. until the flap begins to move and then you know where the check valve begins to open.
You can then turn the pump to full speed and see how much flow the pump is putting out from the pump display.
For example the total flow might be 120 GPM at full speed and some flow is going through the heater and some is going through the bypass but you won't know exactly how much is going through the heater and how much is going through the bypass unless you put a flow meter on the line going into the heater.
If you have the flow meter, then you will know how much is going through the heater and how much is going through the bypass.
The flow switch should be able to always ensure that the flow is above 40 GPM.
New model = 8/2020 and later?The new model does not have a Service System light.
The heater needs 40 gpm.This all makes sense but I'm still trying to understand the relationship between the Spring Ck Vlv and the Jandy Ck Vlv. Also what spring rating is required or whether it's needed at all.
Speaking of minimum length for piping, I thought I read that there' a minimum length recommended for other lines, perhaps from pad edge and connecting to the pump(s) suction?
I don't know the exact date where the new heaters are the new model.New model = 8/2020 and later?
I think a 3.5 lb has been the educated guess all along. However, I'm concerned about buying one rating to only find I need another one and have to eat the cost.The Jandy JXi is a similar design and it shows 4.5 feet or 2 PSI head loss at 40 GPM.
Assuming the MasterTemp has a similar head loss curve, the spring tension should be at least 2 PSI.
For 7 feet of head loss, that is 3 PSI and a 3.5 lb. spring should only open when the flow going to the heater gets to about 48 GPM or higher.
It surprises me that Pentair doesn't provide the heater data like Jandy does. That would certainly make things easier. I sent an email to my PB last week advising I had tried to contact Pentair to find out more about the spring rating. They, in turn, forwarded it to their rep. We'll see if anything comes to fruition.You can ask Pentair for the head loss curve for the MasterTemp if you want to.
PART # 9431A
MANUFACTURER CODE 1095-20
ALTERNATE PART #'S 109520, 26-350-1002
INYO # 9431A FLO CONTROL # 1095-20 GENERAL DESCRIPTION: THIS IS A BYPASS CHECK VALVE THIS IS NOT USED TO PREVENT BACKFLOW LIKE MOST CHECK VALVES THIS IS USED TO ALLOW WATER TO GO AROUND A FILTER OR OTHER EQUIPMENT BY GOING THRU ANOTHER PLUMBING PATH THAT MEETS THE FILTER PLUMBING PATH DOWNSTREAM VALVE TYPE: SPRING OR SWING SPRING TYPE SPRING STRENGTH: 5 LBS. OPENS AT 5 LBS PRESSURE AND IS FULLY OPEN AT 17 LBS OF PRESSURE MATERIAL: WHITE SCHEDULE 40 PVC PIPING CONNECTIONS: 2" SLIP (ACTUAL INSIDE DIAMETER IS 2-3/8" FOR 2" SLIP) DEPTH OF PLUMBING CONNECTION: 1-3/8" (THIS IS HOW FAR THE PIPE WILL EXTEND INTO THE 2" SLIP) TOTAL LENGTH: 5" MAXIMUM OUTSIDE DIAMETER: 2-3/4"
Well, I took the cell out and this fell out. It was big enough to block approximately 80% of the inlet to the cell. Its bee there for some time too as I was immediately able to reduce the rpm of the pump from 1500 to about 1050 and my filter pressure dropped from about 5 psi to 1 or 2 psi prior to bumping the rpm.
It looks like similar material to the heater inlet outlet manifold where the piping connects and it has a broken spot in the center of the back. Any ideas what it is or where it came from. Everything works fine and that's been there for some time. So at least there's that.
Everything is less than a year old and the PB is coming to look tomorrow.
Assume the distance (5x pipe i.d.) is based on an industry standard/best practices? Are there other standards/best practices with regards to minimum distances for the equipment pad for equipment or piping in general?The distance from the elbow to the pump should be 15" based on the 3" pipe X 5.