Pump Troubleshooting For Pool Openings, Part 1

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In springtime, after being shut down for an extended period of time, pumps may experience a range of problems including failure to prime, failure to start, unexpected shutdown and worrisome noises resulting from degradation of components.
In springtime, after being shut down for an extended period of time, pumps may experience a range of problems including failure to prime, failure to start, unexpected shutdown and worrisome noises resulting from degradation of components.

In the next few months, pools throughout the North will be opening, which means pool pros will soon encounter troublesome pumps that do not seem eager to come out of hibernation. The advice in this two-part article is specific to the common issues found with pumps when opening a pool after an extended period of time.

Common Pool Pump Problems At Opening:

Pump will not prime

Priming a pool pump is the process in which the pump begins to draw water from the pool and expel air from the plumbing system through the return lines into the pool. A pool pump that starts and runs, and otherwise sounds good, but does not seem to draw any water into it, likely has a problem priming.

Pump will not turn on

A pump that does not turn on, or make any noise when turned on, has a problem starting. This is not the same as a pump that runs but does not draw water. This is also different than a pump that turns on but then turns itself back off in that the electrical supply seems to be working, but the pump is unresponsive.

Pump turns off

A pump should not turn itself off β€” any pump that does requires further investigation. A pump can potentially turn itself off after extended periods of running, but this issue can also manifest as soon as the power is switched on. The pump may make noise briefly before turning off, or it may be instantaneous. (We'll go into detail about this next month in Part 2.)

Pump does not sound right

There are a few different conditions that could result in a pool pump that just does not sound quite right. These can include a motor that sounds like it cannot raise RPM (struggling) and can often include squealing, screeching or metallic humming noises that indicate worn components in the motor. Pumps can also exhibit a violent shudder and/or shake, resulting in a distinct change in how the motor sounds. This may repeat itself in a cyclic rhythm. (We'll go into detail about this next month in Part 2.)

When you're having trouble getting a pump going, start by figuring out where your issue fits in the above descriptions. From there, we can begin to formulate potential causes.

RELATED: Why Pool Pumps Overheat β€” And What You Can Do to Stop It

What to Do When the Pump Will Not Prime

So you're opening a pool for the season, but the pump is giving you problems. You have identified that the pump will turn on and run β€” and it's not turning itself off. The problem: The pump will not prime. This is by far the most common pump issue owners and pros will encounter in the spring. There are several reasons why this might happen, but if you take your time and check each of these one by one, you will most likely find the problem.

Priming the pump

Priming the pool pump simply means adding water to it. This is a normal process for any pool pump that is located at a higher elevation than the water level in the pool. Every time you stop the pump and open the normally closed-loop plumbing system, the water in your suction pipes will gravity drain back to your pool.

In order to prime your pool pump, you need to manually add water to it to help it draw water up through the suction lines. When you first open your pool for the year, it will usually take more effort to prime your pump than normal. If you are used to adding a bucket of water to your pump and turning it on, or maybe not priming it at all during the regular swimming season, it could be that your pump just needs more water.

Normally the pipes to your pool will not be completely dry. Even if the majority of water drains back to the pool, you will probably still have some water trapped in the lines. But when you first open the pool for the year, the plumbing lines are bone dry on the inside. During opening season, it's normal to prime a pump three times as much as you normally would during the mid-season.

You should add water to your pump, usually two gallons of water or so at a minimum, close the lid and turn the pump on. Let the pump run up to five minutes. If the pump has not picked up the prime by then, shut it off to avoid overheating and add another two or three gallons of water to the front of the pump before trying again.

Repeat this a minimum of five times before you give up. That means a minimum of 10 gallons of water poured into the pump, coupled with a total of at least 50 minutes of (supervised) run time to allow the pump to try to work through it. If you have completed these steps and the pump has still not primed, you can be confident you've tried all the normal steps and can move onto exploring other potential causes.

Other sources of priming trouble:

1. Make sure the water level is at least half way up the skimmer mouth and NOT below the mouth of the skimmer.

2. Check the skimmer: Did you remove the Gizzmo or winterizing plug used in the off-season? Also make sure the weir door is not stuck.

3. Also ensure you have removed the return port winterizing plugs.

4. Check your suction-side and return-side manifolds to be 100 percent sure you do not have a closed valve dead heading the pump.

5. If you have a sand filter, be sure to check the filter head and set it to the "filter" setting (not "closed" or "winter").

6. If you have a cartridge filter, be sure you have not reversed the in and out pipes when it was put together.

7. Double check that the pump lid gasket is lubricated and seated correctly on the pump housing.

8. Quite often, O-rings for valves and unions fall out during winterizing. Make sure the pump is not missing any.

9. Check the plastic winterizing port plugs on the bottom of your pump; they may be loose or leaking. Tighten carefully to avoid breaking them.

10. See if a suction-side leak has developed during winterizing. If you have any threaded connections, these should be checked and redone.

If you need to test for suction side leaks, try running a garden hose over the suction-side manifold and fittings while the pump is running. If a leak is present, the water from the hose should temporarily resolve this just long enough for you to notice the pump working for a moment. (You can also sometimes get similar results with plastic bags, which will get sucked into any leaks on the suction side of the pump.)

If you have gone through each of the above steps and still cannot not identify why the pump will not prime, then there are only a few possible reasons left. When a previously reliable pump is unable to prime in spring, it is far more likely that the plumbing lines are compromised...usually via a leak that was either introduced or worsened over the winter. The only way to be absolutely certain of the condition of your plumbing lines is to pressure test the suction lines and determine if they are leaking. If you have a crack or break in the suction lines anywhere, you are going to have a pretty hard time getting the pump to prime...if at all. If you have gone through all of the steps above and your pump still will not prime, you are most likely looking at a blockage in the line, or more commonly, a leak.

At this point, just about every pool technician will try to force water through the skimmer suction with a garden hose. While putting some water under pressure down into the skimmer suction might help, be aware that you do not want to cover the suction hole with your hand. You can feed the hose a few inches down into the suction port opening, but avoid making a seal with your hand around the opening as the suction power from the pump is dangerously strong. If the pump were to pick up prime while you are covering the suction port with your hand, there could be enough power in the pump to cause you to become stuck and very seriously injured.

There exists a product called a "priming plug" (or at least it used to exist). This allows you to attach a garden hose to a winterizing plug and force-feed water through the suction line all the way to the pump. I have not seen these for sale in decades now, but if you know where to get one or how to make one, then using the pressure from your garden hose to push water from the pool to the pump can be a great way to get a stubborn pump primed.

What to Do When the Pump Won't Turn On

So you flip the switch (or breaker) and find the pump doesn't respond in any way. No shaking, humming, no sound of any kind. It doesn't trip the breaker or do anything notable at all. What now?

In this case, there are only a few possible causes. The total lack of symptoms is actually the biggest symptom itself.

Most of the troubleshooting for this specific problem involves testing the electrical voltages in various places. If you do not understand electricity, are afraid of it or are not qualified to safely test electrical values, you should certainly not attempt to diagnose electrical problems with a pump. (If you fall into this category then you are limited to turning the pump on at the switch. If that does not work, you can try investigating the electrical breaker that supplies the circuit for the pump for any obvious signs that it is off (for the winter) or has tripped out for some reason. If the answer is not obvious to you, you have reached the end of what you can safety troubleshoot yourself then your next move should be to contact an electrician or reliable handyperson who can check your voltages for you.)

At this point, you either have a pump problem or an electrical problem, and you need to be able to test voltages to know which you are dealing with.

When testing the electrical system, you want to verify that you have power every step of the way. The circuit should leave the main electrical panel from the home and travel out to the pump location, where often you will find another box, breaker or switch of some kind. If you can test at the pump and you have no power, test at the next closest junction to see if you have power there. If not, keep working backwards towards the main electrical panel until you find the place where the electricity stops. You could have a bad wire or connection somewhere, or potentially some damage to your electrical service from rodents. If you can test and have line voltage all the way to your pump, but your pump still will not make any noise, or move, then you have reached the end of how far you can troubleshoot this pump problem.

In this case, your next step is to call the 800-number on the side of your pump and ask to speak to technical support. If you explain there is voltage reaching the pump (tell them the actual number), but the pump remains unresponsive, they should be able to advise specifically what the problem and repair solutions are. You most likely will find yourself replacing the motor at the least, or the entire pump at most if the pump is not young enough to warrant swapping the motor. If the pump is under five years old consider a new motor. If the pump is over five years old, upgrading may very well be the best plan.

Please note:

Other than testing to make sure the power is reaching your pump, you should avoid any component-level testing or additional electrical diagnosis inside your pump past the point where the line voltage supplies the pump in the termination junction box. 

This ends part 1 of this discussion of common pump problems found on pool openings, focusing specifically on priming problems and power failure. This two-part series will conclude with how to address unexpected shutdowns and what do to when the pump just doesn't sound right. Read it here.

Steve Goodale is a renowned writer, humorist and swimming pool expert who lives in Ontario, Canada. You can learn more about Steve, as well as swimming pool construction, maintenance and repair (and have a few laughs) at his website: SwimmingPoolSteve.com.

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