Franklin constant pressure Subdrive 300, water well

Old 08-05-12, 01:06 PM
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Franklin constant pressure Subdrive 300, water well

Our water well is 6 years old, and we have gone through two Franklin SubDrive 300 NEMA 4 units. Our well has a 3 1/2 gallon in-well pressure tank. The manual for the unit specifies that a minimum 20 gallon pressure tank is required. A well drilling company (not the one that drilled our well) told me that 6 years ago, Franklin did not have the 20 gallon minimum requirement, and this resulted only after many failures of the unit. Does anyone know if this is true? I am trying to determine if the manufacturer or the well driller is at fault for our problems.
A second question is whether we should abandon the constant pressure unit, and just use the tried and true old fashioned system. We will have to have an external pressure tank whether or not we use the Franklin subdrive 300, and for a residential house, I can't see what the advantage is to an expensive constant pressure unit that breaks. What are the pros and cons of just getting rid of the constant pressure unit. Thanks
Old 08-07-12, 02:50 PM
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Oh my goodness! So many problems with the variable speed constant pressure systems today. I have tried to show people on this forum how to fix these problems in the past, and was reprimanded for promoting a “product”. So I don’t help out much here anymore, because they won’t let me show how to solve these problems. Maybe with all these problems with variable speed pumps on this forum today, they might actually let me show how to solve these problems but you will need my “product”.

The Cycle Stop Valve was designed to replace variable speed pumps almost 20 years ago. It is completely mechanical, long lasting, simple, inexpensive, works with very small pressure tank, and makes pumps last many times longer than normal.

Larger pressure tanks just makes the time with low pressure take that much longer. And a pressure reducing valve on the discharge of the tank may give you steady pressure but, will still let the pump cycle itself to death. A Cycle Stop Valve is placed before the pressure tank. It will deliver the constant pressure you need for things like instant water heater, and keeps your pump from cycling as well.

I hope the mods don’t mind if I answer these questions as it doesn’t seem anyone else knows about them, and Constant Pressure Valves are all I do.

Last edited by waterwelldude; 08-07-12 at 08:47 PM.

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