Wayne Sump Pump Buying Checklist: Float Switches, M137, and the Check Valve Question

Let's clear one thing up: this article is about Wayne pumps. If you came here looking for Wayne Gretzky and Usain Bolt, that's a different kind of race. If you actually meant a Wayne Dalton garage door opener, that's a different Wayne too. This one handles water.

Who is this for? If you're the person who gets asked to 'order a sump pump' without much more detail, this checklist is for you. I've been managing facilities purchasing for about six years. I process somewhere between 60 and 80 orders a year, across roughly eight vendors, and about $40,000 in facilities purchases. Sump pumps are a small slice of that, but they make up for it in stress. When one fails, everybody hears about it.

Use this checklist when you're replacing an existing pump, choosing a pump for a rental property, or reviewing an order that someone else prepared. Here's the structure: six steps, and each one has a clear check point.

Step 1: Confirm the pump type for your pit

Wayne makes submersible pumps, utility pumps, and sump pumps. They're not interchangeable. A utility pump is portable and works for draining a flooded area. A sump pump sits in a pit and handles recurring groundwater. A submersible pump, which is one type of sump pump, stays inside the pit and runs quietly. A pedestal pump keeps the motor above water and is easier to service, but it can be louder and less effective in deep pits.

I went back and forth between submersible and pedestal for a retail space with a shallow pit. Pedestal was easier to service, but the pit had enough depth to allow a submersible, and the tenant wanted quiet. I chose submersible.

Check your pit depth and diameter before you order. Check whether you need a pump that runs continuously or only during storms. And check the discharge pipe size. A pump with a 1-1/2 in. discharge might be fine for one building and completely wrong for another.

Step 2: Pay attention to the sump pump float switch

The sump pump float switch is the most likely failure point. There are tethered floats, vertical floats, and electronic sensors. Tethered floats need room to swing. If the pit is narrow, a tether can catch on the outlet pipe. Vertical switches are more compact, but they still need clearance. Electronic switches have fewer moving parts, but they add cost.

I learned this after a communication failure. I said 'pump with a float switch.' The vendor heard 'any float switch that fits.' Result: two pumps with tether floats that kept catching on the discharge tee. Not ideal. Worse, one of them caused the pump to cycle constantly. We had to pull both pumps out and rebuild the floats with different hardware.

So when someone writes M137 sump pump on a requisition, I don't assume the float switch style. I open the spec sheet. The model number is a start, not a complete specification.

Step 3: Does a submersible pump have a check valve?

Short answer: not usually. Most submersible pumps do not come with a check valve built into the pump housing. You install one on the discharge line. Some models include an internal check valve, but it's not safe to assume. Read the cut sheet or the installation instructions.

When I took over purchasing in 2020, I assumed every submersible pump had a check valve included. It didn't. We installed a new pump, it moved water, and then it cycled again about thirty seconds after it stopped. A plumber pointed out that water was draining back through the impeller because there was no check valve. Looking back, I should have ordered check valves at the same time as the pumps. At the time, I didn't even know to ask.

So, does a submersible pump have a check valve? In my experience, usually no. If the spec sheet doesn't say 'check valve included,' order one separately. A spring-loaded check valve in the discharge line prevents backflow and keeps the pump from short-cycling.

Step 4: Calculate total cost, not just unit price

Here's where I get a little annoying. A $189 pump that dies in two years is not cheaper than a $279 pump that lasts six years. Not if you count labor, downtime, and the phone call from your property manager.

What I mean is that the 'cheapest' pump isn't just about the sticker price—it's about the total cost including your time spent managing a replacement, the risk of a flooded storage room, and the possibility that a tenant loses inventory because someone tried to save $40 on a backup pump. If you ask me, that's where the savings come from: fewer emergency calls.

In my experience managing purchasing for five years, the lowest quote has cost us more in about 60% of cases. That's not a scientific sample, but it's why I'm skeptical of cheap. To be fair, budget tiers exist, and a basic utility pump is fine for a one-off drainage job. For a basement with a server room above it, I spend more.

When I compare pumps, I write down the unit cost, check valve cost, float switch cost if it's separate, shipping, and expected labor time. Then I compare that against the expected service life. Not glamorous, but functional.

Step 5: Verify the specs before the PO goes out

This is the step people skip. They order a model number and don't check the details. For example, a M137 sump pump might look identical to an older one but have a different voltage, cord length, discharge size, or switch style. Spec sheets change. As of 2025, I still confirm the current product data rather than trusting an old purchase order.

Here's what I check before sending a PO:

• Voltage: 115V or 230V. This matters more than you'd think when the job site has only one outlet.
• Pumping capacity in GPM at 5 ft and 10 ft lift. Horsepower alone doesn't tell the whole story.
• Discharge connection size and thread type (pipe threads are not universal).
• Cord length. A pump with a 10-ft cord that's installed in a 12-ft pit becomes an extension cord problem.
• Certifications. UL 778 is a common standard for motor-operated water pumps. If your inspector or insurer asks, you'll want that number.

If the float switch is ordered separately, check that too. A sump pump float switch is not one generic part. The tether length, mounting bracket, and contact rating all need to match the pump.

Step 6: Test after installation, and stock a spare

After installation, pour water into the pit. Watch the float engage. Time the run cycle. Listen for vibration. Then do it again. It sounds obvious, but I've had a vendor sign off without testing, and the pump never turned on because the float couldn't lift—the pit lid was pressing down on it.

Also, keep a spare float switch and a check valve in inventory. A $25 float switch can turn a $1,000 emergency call into a routine maintenance task. Don't hold me to the exact price, but last time we ordered a compatible float switch, it was in that range. It's one of those things you don't think about until a pump is cycling every minute at 2 a.m.

Three mistakes I still watch for

One: assuming the submersible pump has a check valve. It probably doesn't. Two: ordering by model number without reading the current spec sheet. The M137 sump pump I ordered this year might not match the M137 from a previous batch. Three: chasing the lowest unit price. The pump that costs the most in overtime usually wins.

Wayne pumps are reliable. But reliable doesn't mean foolproof. If you check the float switch, confirm the check valve, verify the specs, and budget for total cost, you'll have fewer flooded floors and quieter facilities. That's all I want.