Franklin Subdrive 3W Utility UT3P Issues - When "Upgrading" Goes Wrong

[SirScoutalot]

In 2024, I upgraded my well pump setup with a new Franklin SubDrive Utility UT3P System, expecting improved performance and reliability. Instead, I’ve faced a cascade of issues that have made me question this so-called “upgrade.”

Just two months after installation, the SubDrive unit failed completely and had to be replaced. Since then, the system has been plagued by intermittent shutdowns triggering fault code F6. Sometimes it runs for a day, sometimes for months but eventually ends up faulting again. Usually, but not consistently, under heavy load. Resetting the system restores function.

Unlike my old pressure switch and tank setup, which ran for decades without issue and was easy to maintain, the SubDrive system is proprietary and complex. I can’t troubleshoot or repair it myself. To my annoyance I've had to call the same techs that installed the system to troubleshoot the Subdrive system. My only answer from them being, it all checks out if it happens again call us and we can replace the unit.

After some research, I’m leaning toward the idea that these systems are designed to be difficult to service without professional help. The reliance on specialized electronics and fault codes makes DIY maintenance nearly impossible. Poor show Franklin! It’s a stark contrast to the simplicity and longevity of traditional systems. If you’re considering upgrading to a Franklin SubDrive Utility System, think twice. My experience suggests that while these systems promise modern efficiency, they often deliver frustration, downtime, and costly service calls. Sometimes, the tried and tested is the better way.

I am considered adjusting the dip switches to lower the horsepower setting from 1 HP to ¾ HP, hoping it might stabilize the system. This would underpower the pump. Would this be likely to cause harm to the pump? Franklin Electric’s own documentation warns against mismatched settings, see attached. Any other ideas on adjustments to the, dip switches, underload or pressure set point, that could remedy the issue? Can I disable the fault from occurring?

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[Valveman]

Sorry for your problem. I fell for the VFD hype back in about 1990. I was also told they were more efficient and worth the extra expense and trouble. However, I found out VFD's actually use more energy per gallon produced. The amps needed to spin the motor decreases with the speed, and everybody thinks they are using less energy. But the pump must run for so much longer to produce the gallons needed that the energy used actually increases. It should be considered false advertising to say a VFD saves energy,

Now you have a "subdrive" with the three phase motor. You are stuck with that Tar Baby until you swap out the three phase motor for a normal single phase motor, which will run on regular house power. Most people replace the subdirve 2 or 3 times before they realize they must change back to a single phase motor if they want "improved performance and reliability".

Like you said, the old pressure tank/pressure switch systems are the longest lasting, most dependable, and even the most efficient. The ONLY problem with the old pressure tank systems was too much pump cycling. Adding a simple Cycle Stop Valve to the old dependable pressure tank/pressure switch system solves that problem while delivering the strong constant pressure you were expecting from the VFD system.

 

[Sponsor]

 

[Fitter30]

Others make filters for incoming and vfd to pump power. This is a electronic device a installer can wire one but it's a electronic devise it's out of their realm.
Here' s the install manual page 16 with wiring and 38 they have filters listed. They also spec a ground wire to pump and drive mounted next to main electrical panel.

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[SuperGreg]

Others make filters for incoming and vfd to pump power. This is a electronic device a installer can wire one but it's a electronic devise it's out of their realm.
Here' s the install manual page 16 with wiring and 38 they have filters listed. They also spec a ground wire to pump and drive mounted next to main electrical panel.

Loading…

www.google.com

The ground wires specified are standard electrical grounding, nothing special there.

 

[Valveman]

After some research, I’m leaning toward the idea that these systems are designed to be difficult to service without professional help. The reliance on specialized electronics and fault codes makes DIY maintenance nearly impossible. Poor show Franklin! It’s a stark contrast to the simplicity and longevity of traditional systems. If you’re considering upgrading to a Franklin SubDrive Utility System, think twice. My experience suggests that while these systems promise modern efficiency, they often deliver frustration, downtime, and costly service calls. Sometimes, the tried and tested is the better way.​

Again, sorry for your problem. Any company in the stock market only cares about their stock holders, which comes at the expense of the customers.

 

[Fitter30]

The ground wires specified are standard electrical grounding, nothing special there.

Ground wire aren't anything special but how they wanted where the drive should be located how the wires are run. Pressure sensor wires if they were extended and the type of wire (low capacitance) and ran separate from power wires. And they do offer two types of filters. My pump doesn't have a ground wire piped galvanized pipe with steel casing.

 

[SirScoutalot]

Yes, its frustrating as it seems to me that the error is not valid. There is no pattern to its occurrence, all the wiring and connections seem in order but there is no way to disable it and stop the system shutting down.

 

[Bannerman]

While 'dirty power' could contribute to a VFD's lack of reliability, as Valveman stated, VFD's are an overcomplicated design which leads to the need for frequent service and repair. In addition, the shorter than usual lifespan compared to a standard well pump system, typically results in customers needing to repeatedly purchase a new expensive replacement system, which is fully expected to further benefit both Franklin and the local Frankin VFD dealer's bottom line.

As mentioned above, consider replacing the existing 3-phase motor with a conventional single phase motor, and replace the VFD controller with a conventional pressure switch. Equipping that simplified system with a CSV will then increase reliability and will prevent cycling while supplying constant pressure without the need for complicated, expensive and hard to obtain components. Just as with the existing VFD system, a tiny 4.5 gallon pressure tank is all that will be typically needed while utilizing a CSV.

 

[Valveman]

Yes, its frustrating as it seems to me that the error is not valid. There is no pattern to its occurrence, all the wiring and connections seem in order but there is no way to disable it and stop the system shutting down.

I can assure you there are no "pump techs" who know how a VFD works. Like they said, if it keeps giving problems they can just replace the unit, which is all they know how to do. "Pump guys" like the pump manufacturers, do not make any money if your pump system last 30 years without any problems. They like it when you have problems, as they make more money. Even if you get this problem figured out, it is just a matter of a short time before you will have problems again. That is just the nature of a VFD pump system. Experts will agree a Cycle Stop Valve is a much better option than a VFD, which is why you won't find a pump manufacturer that promotes Cycle Stop Valves.