A Check Valve Almost Cost Us a Goulds Pump Job: Lessons From a May 2024 Callback

The Callback That Changed My Checklist

The pressure switch was clicking every four seconds. I remember the date, May 14, 2024, because it was the third callback in two weeks involving a Goulds pump in the same subdivision. I'm a quality/compliance manager at a pump distributor. I review every pump order and service job before it reaches customers—roughly 200+ unique items annually. Maybe 180, I'd have to check the system. I've rejected 8% of first deliveries in 2025 due to spec mismatches. But this wasn't an order. This was a Goulds submersible pump we'd sold and installed six weeks earlier.

The customer's first question on the phone was: 'Does a well pump have a check valve?' The short answer: most submersible well pumps do. This Goulds model had one built into the discharge housing. But the short answer wasn't enough, because the pump was still losing pressure overnight.

The Parts Diagram Saved Us

I sent a senior service tech to the site. He checked the pressure tank, the pressure switch, the wiring. Oh, and the control box relay—that was fine too. The pump came on, built pressure to 55 psi, and shut off. Then over about five minutes, the pressure bled back down to 30 psi. Classic backflow. He pulled the line diagram from the Goulds pumps parts diagram library and traced every fitting from the pump to the tank.

The exploded view showed the factory check valve in the pump discharge. The flow arrow pointed the right way. But on the actual job, someone had reused an old in-line check valve between the pitless adapter and the pressure tank. The rubber flapper had folded over and was stuck on a piece of scale. That's why the pressure dropped. The pump itself was never the problem.

That was my trigger moment. I didn't fully understand why service manuals spend so many pages on check valves until one folded rubber flapper caused a $5,000 service call. The manual had been warning me about check valves for years. I didn't listen until this callback. If the pump had run dry long enough, the redo could have hit $22,000. The old check valve was a $45 part. The service call, including pulling the tech off another job, cost more than $800. Saving $45 was one of the worst trade-offs I've seen.

To be fair, not every well pump needs an additional check valve. The key is verifying what the specific model requires and what the installation actually has. The Goulds pumps parts diagram for that model showed every component in the discharge assembly. Instead of guessing, the tech took a photo of the diagram, labeled the flow direction, and checked each part one by one.

The manual said the pump's built-in check valve prevents backflow through the pump. But it doesn't protect against a downstream valve that sticks. When a check valve fails open, water drains back into the well and the pump short-cycles. That's the answer I now give to 'does a well pump have a check valve?' It depends on the model, and it's worth checking the diagram before you rely on it.

Torque Specs and the Service Technician Tool Set

After we replaced the check valve, the tech had to reassemble the discharge pipe and the pump housing. He reached for a standard ratchet to tighten the bolts on the motor housing. I stopped him. For that job, the spec required a 3/8 inch drive micrometer torque wrench. Not a beam-style torque wrench, not a calibrated feel—a micrometer-style wrench with a scale you can set in advance.

Our service technician tool set includes one on every truck now. But it wasn't always that way. Some of our older techs used to carry a $40 beam-style torque wrench. Beam-style wrenches are okay for rough work, but they're easy to misread in a cramped space. The micrometer type clicks when you hit the set value, which matters when you're kneeling next to a wet pit.

The torque spec for the discharge bolts was in the installation manual: 20 ft-lb for this particular model, with a 10 ft-lb follow-up on a new gasket. I'm not going to quote that for every model—you need the specific drawing. But the principle applies across the Goulds lineup, including the Goulds Water Technology water circulating pump I checked later that month.

Later that month, I reviewed a separate installation of a Goulds Water Technology water circulating pump used for a hot-water recirculation loop. The pump was mounted correctly, but the installer had left the torque wrench in the truck and used an adjustable wrench on the volute bolts. That's a red flag for me. The housing is cast iron, and an overtorqued bolt can crack the flange. We sent a tech back with the service technician tool set and a 3/8 inch drive micrometer torque wrench to redo it. No damage that time, but the labor cost shouldn't have happened.

What I'd Do Differently

Looking back, I should have added 'verify check valve condition' to the pre-install checklist before the pump went in. At the time, the built-in check valve seemed like enough. It wasn't. If I could redo that decision, I'd make the parts diagram review a required step for every well pump and every circulating pump. The diagram is free. The manual is free. The cost is just a few minutes of attention.

The fundamentals haven't changed: check valves still stop backflow, torque specs still prevent leaks, and a parts diagram still shows you what's inside. But the execution has transformed. In 2022, when I implemented our verification protocol, we had PDF manuals but not everyone used them. By 2025, every service truck has a tablet, and there's no excuse for guessing. What was best practice in 2020 may not apply in 2025.

At the same time, I don't want to dismiss the old way. A lot of experienced installers can feel a flange bolt and get it close. But close isn't a spec, and when I'm putting a Goulds pump back into service, I need documented values. In my opinion, the 3/8 inch drive micrometer torque wrench should be in every service technician tool set that touches a metal pump housing. The beam-style one can stay in the drawer.

Bottom line: the check valve question isn't a trick. It's a starting point. The parts diagram gave us the map, the torque wrench gave us the precision, and the service technician tool set made it practical. If you're doing this work, I'd argue those three things are non-negotiable.