Jockey pumps are the unsung heroes of a fire protection system, quietly maintaining pressure so the main fire pump doesn't have to start for minor drops. Because they are smaller and seemingly simpler than the main pump, people often don't spend as much time on them.
Whether you are gathering information to replace an aging jockey pump or installing a brand new one, skipping over the details often causes more problems than it solves. By following these guidelines, you can make the most efficient use of your time and ensure your system is installed right the first time.
6 Steps to Gather the Right Specs for Replacement
If you are replacing a jockey pump, taking a few minutes to write down the correct information will save everyone a massive headache. Here are the six things you need to record before calling us:
1. Get the pump model number and serial number.
It’s on the pump, not the motor itself. This seems obvious, but 4 times out of 5, people copy down the wrong information because they simply look at the wrong nameplate—especially on turbine jockey pumps.
On turbine pumps, the motor makes up 75% to 90% of the unit. Because of this, people look at the whole assembly, call it “the pump,” and write down the info from the biggest, easiest-to-read nameplate. Unfortunately, that is the motor nameplate. The actual pump nameplate will be on the smaller pump end, perpendicular to the motor. Don’t be fooled! Aurora turbine serial numbers usually look like “94-65478,” and model numbers are short, like “D03-BR.”
Rule of Thumb: A pump model and serial number is usually less than 8 characters. If you are writing down a long string like “1ZK56CW45590BTGGA,” you are looking at a motor ID number.
2. Get the MOTOR voltage, HP, Full Load Amps (FLA), and Service Factor (SF).
These are always found on the motor nameplate. While we are primarily after the HP and voltage to ensure the new pump operates on your current electrical setup, getting the FLA and SF helps us minimize any necessary modifications to your existing jockey controller. Generally, you want to match the existing HP, or you should expect to make panel modifications.
3. Get the rating of the main fire pump.
This allows us to evaluate if your new jockey pump—whether an exact replacement or not—can match the churn pressure of the fire pump system. All jockey pumps, if selected properly, must be able to match the fire pump pressure boost.
4. Get the static suction pressure.
What is the fire pump suction gauge reading? Does this figure vary significantly throughout the year? What is the minimum reading? Write this down!
5. Get the jockey pump controller pressure switch information.
What is the “ON” setting? What is the “OFF” setting? If this is not readily apparent, ask the building personnel what system pressure they like to maintain. We will use this number, along with your static suction pressure, to determine the exact pressure boost the new pump must provide.
6. Evaluate the system size and piping.
Take a look around. Will this new pump only charge a relatively small section of pipe, or is it expected to fill a massive system with extensive underground piping? Note what you can about the accessibility of the pipes and fittings.
Note: If you accurately gather items 1 and 2, and the pump is still being manufactured, replacing it is incredibly straightforward. Items 3 through 6 act as the perfect safety net if there are discrepancies.
4 Bonus Items for a Perfect Swap
Want to be completely covered? Grab these four bonus items while you are in the pump room:
Controller details: What is the jockey pump controller make, model number, and serial number?
Actual voltage: Carefully measure the incoming voltage to the controller with a voltmeter. The original panel might have been ordered for the wrong voltage and modified without updating the nameplate.
Relief valve status: If the pump has a relief valve, is it functional, and can it be re-used?
Connection sizes: What are the suction and discharge connection sizes on the existing jockey pump?
Avoiding Common Startup Pitfalls
Once you have the right pump, you still have to install it correctly. Here are three items that will save you effort when field technicians show up for startup:
Pump Rotation and Motor Rotation
When wiring up a three-phase motor on a jockey pump, it’s remarkably easy to get the phasing backward. A centrifugal pump running backward will often still move some water, but it will only produce a fraction of its rated pressure and flow. Contractors often assume the pump is defective because it won't hit the cut-out pressure. Always "bump" the motor to verify the rotation matches the directional arrow on the pump casing before putting it into full service.
Don't Forget the Air Vent
Most modern jockey pumps come equipped with an air vent or bleed plug near the top of the casing. When you fill the piping system with water, air gets trapped inside. If you don't bleed this air out before starting, the pump can become "air-bound." It will spin without moving water, rapidly overheating and destroying the mechanical seal. Always crack that vent to purge the trapped air until a steady stream of water flows out.
Minimum Run Timers
Minimum run timers keep the pump running for a set duration to prevent it from short-cycling. While this sounds helpful, NFPA 20 (4.25.4.2) clearly states: "Running period timers shall not be used where jockey pumps are utilized that have the capability of exceeding the working pressure of the fire protection systems."
If the system quickly reaches its satisfied pressure, but the timer forces the pump to keep running against a closed system, it operates at its maximum "churn" pressure. If this is higher than your piping's rating, it could cause a blowout.
Need help with your next fire pump or jockey pump replacement?
Take a few photos of your nameplates, jot down your pressures, and reach out to our team today. We're here to help you check for common errors and ensure your system is perfectly matched.
