We’ve spent a lot of time talking about Waukesha’s industry leading line of positive displacement pumps, but in today’s post we wanted to circle back to C Series Centrifugal pumps. Specifically, tips and tricks to help you figure out what that pump that has been sitting under that tank in the corner slow dripping for 30 years is. So let’s get into it.
Pump serial number is probably the easiest way to run down which you have. More times than not, this is found on the pump power frame or adapter. This is the part that bolts directly onto the motor. The pump serial number will tell us everything we need to know about the pump- model, port size & type, seal type, elastomer type, impeller trim, motor frame size, and usually whether or not it was sold with a motor. That’s quite a bit of info.
The challenge with the serial number, however, is that if you’re an end user, you probably don’t have ready access to a manufacturers serial number database, which means calling someone who might not get back to you right away.
The other challenge with serial number is that with so many different manufacturers- Waukesha, Ampco, Topline, Dixon, and Alfa Laval, just to name a few, it’s pretty much impossible to find one partner who has access to all of that information. So what else can we do to identify the pumps? Let’s keep moving.
Port & Backplate Size
The next thing we can look at is port size. With the C Series, we have 5 common model sizes- C100, C114, C216, C218, and the C328. The first digit typically denotes the pump inlet port size and the second digit will denote the discharge size. So a C216 will have a 2” inlet by 1.5” discharge. The C328 will have a 3” inlet with a 2” discharge.
The last digit denotes the backplate size, as well as the maximum impeller size. So the largest impeller a C114 can take is a 4” impeller, while the largest impeller a C216 can take is a 6” impeller. You can measure your backplate by measuring the diameter of the backplate from the casing gasket groove. You can also determine the size of your impeller by measuring from the impeller tip to the casing gasket groove, multiplying by 2, and subtracting from the pump full impeller size. Impellers will typically be trimmed in 1/8” increments.
Seals, Elastomers, & Motor Frame Size
So now that we’ve talked about how to figure which model we have and the impeller size, we just need to nail down the seal type, elastomers, and motor frame size.
The motor frame size is the easiest. It is found on an NEMA motor tag (check out our post on motor name tags here).
Next, let’s look at the seal. We should be able to determine the seal type without taking the pump apart. Simply remove the pump guard and see what you find. If you see a spring, cup, and black seal, you most likely have a Type D Seal. This is by far the most common seal type we see. If you see a multipiece backplate, spring, cup, white, and black seals, you’ll know that you have a Type DG seal. The DG seal is the second most common seal type. And if all you see is stainless (no spring or seal components), you’ll know you have a CB+ type internal seal. Generally, in the sanitary space, we only see this type of seal in brewing applications.
Elastomers also shouldn’t be too difficult, but we will need to take the pump apart to see them. Refer to our post on gasket color codes to help identify your gaskets- it applies to your C Series O-rings as well.
So the next time you are wondering what kind of C Series pump you have, use these simple tips to help narrow it down. Ideally, you’ll have a Waukesha Serial number a Triplex Sales Engineer can look up quickly. But if you don’t, check the port size, measure the backplate, and take a look to see what seal type you have. This should get you pretty darn close. From there, contact a Triplex Sales Engineer and we’ll be happy to help get you the rest of the way!