Why is my spa pump not working? (Common spa pump problems and solutions!)

Some of the common problems that spa pumps have and how to diagnose and solve them.

Why is my spa pump not working hero

The circulation pump is one of the most important components in your spa - it moves water through your filtration system and circulates your water evenly throughout your spa. When everything is working properly, this means your water is kept clean and crystal clear.

In this article, we’ll explain how a spa pump works and some of the common issues that you may experience with your spa pump and how to resolve them.

How does my spa pump work?

Your spa pump has two parts to it - the dry end and the wet end. The dry end in your spa pump is where the electric motor lives which drives the pump. The dry end does not have water running through it.

The ‘wet end’ drives water using an impeller, which pushes water through the pump, creating the circulation of water in your spa.

Between the wet end and dry end of your pump is a seal called a ‘mechanical seal’ - this seals around the drive shaft to prevent water from getting into the motor and electrical components in your pump.

As the pump operates, it draws water through the filtration section in your spa, cleaning and filtering the water and circulating evenly throughout the spa.

How long should my spa pump last?

Most spa pumps have a warranty term between 1 and 2 years, but with proper care and maintenance in your spa, a pump should last between 5 and 10 years.

Your pump life will depend on how much use your spa has had, and if you are maintaining your spa correctly.

If you don’t clean your spa filters regularly and don’t maintain your water quality correctly, your pump will have to work a lot harder - and could fail more quickly. Damage to the pump caused by incorrect chemical balance will not be covered under warranty by most manufacturers.

How long should my spa pump run per day?

Your spa pump should run for 12-18 hours per day circulating the water in your spa and ensuring it is thoroughly filtered and that your sanitising chemicals are evenly distributed.

How do I know if my circulation pump is working?

A spa circulation pump operates pretty quietly so you may not hear it operating from a distance. Your circulation pump will run for 12-18 hours per day moving water around.

Look out for water movement which will indicate that your pump is working, or remove the side panel of your spa and listen closely to hear the pump.

How do I identify my spa pump?

If you need assistance identifying your spa pump, we can help you in many cases. Follow these steps to gather all the information then send that to us and we’ll help your identify your pump or a suitable replacement.

  1. Turn the power off to your spa.
  2. Remove the side panel to gain access underneath your spa.
  3. Locate your pump and take a clear picture of it.
  4. Take another picture of the pump specification plate (showing model number, amps, power output (watts)
  5. Take a picture of your spa
  6. Note the make and model number of your spa if visible
  7. Email all these details to support@spaworld.com.au
Example of a pump specification plate

Example of a pump specification plate

What causes a spa pump to fail?

Over chlorinating your spa can cause your water to become too acidic, this can begin to eat away at the mechanical seal on your spa pump and eventually allow water to enter the dry end of your spa pump. Pump failure in your spa is generally not covered by the manufacturer’s warranty if water balance is not correctly maintained.

Your circulation pump is designed to move all the water in your spa evenly through your filters to keep it clean and clear. As time passes, your filters will collect particles of dirt, grime and oils that are in your water and you will need to clean your filters out and eventually replace them.

If you don’t clean and replace your filters regularly, the pump has to work a lot harder to move water around in your spa. As a result, your pump is under more strain, which can cause premature failure.

How do I know if my spa pump is bad?

If your pump starts making a louder-than-usual noise, vibrating, or providing reduced water flow, this could be an indication of a problem. In some cases, components in the pump can be replaced, other times you may need to replace the pump.

On modern spas, the pump is connected to the spa controller using a data cable. This enables the controller to give an error message which can help you determine if there is a problem with the pump.

Should my spa pump be leaking water?

No! Your spa pump should not be leaking water. If you see water on or around your spa pump, you should check the unions to ensure they are all tightly done up. If you have checked the unions then your pump may have a problem and need to be repaired or replaced.

Some of the areas to check for water leaks in your pump are the mechanical seal, unions, and impeller.

Why won’t my spa pump prime?

If your spa pump won’t prime, In most cases the problem is an airlock in your spa plumbing system. This can also be caused by leaves or debris trapped in the filtration area of your spa, but the airlock is the most likely cause.

A couple of common errors relating to spa pumps are error 3 (ER3) and error 4 (ER4). ER3 is a water prime failure message and usually means there is an airlock in your pipes. ER4 is the Thermal trip error code and indicates there is not enough water flowing through the heater element.

In many cases, these errors can be easily corrected and we’ve written a detailed article on how to fix spa error code 3 (ER3) and error code 4 (ER4)

Why is there no water pressure in my spa? (What causes my spa pump to stop circulating?)

The most common cause of low or no water pressure in your spa is a blockage in your filtration system. To fix this, turn your spa off, remove your filters and clean out any leaves and debris that may have accumulated around your filter box. Low water pressure can also be caused by dirty or clogged spa filters, so now is a perfect time to soak your filters overnight in a filter cleaning solution. After soaking, rinse your filters thoroughly with clean water then replace them in your spa.

Read our detailed guide on cleaning your spa filters.

Your filters won’t last forever, we recommend replacing your filters every 12-18 months depending on the usage of your spa. In a spa with heavy use, you will need to replace your filters more regularly.

Another cause of low water pressure in your spa is a worn pump impeller. The impeller is the component that pushes water through your pump as it rotates on the drive shaft. Over time, your impeller will wear and may need to be replaced.

If you’re hearing whining or grinding noises from your pump, the motor in the pump may be nearing the end of its life, in this case, it’s time to replace the whole pump altogether.

Why does my spa pump keep turning off?

If your spa pump keeps turning itself off, it is most likely either faulty wiring or a worn motor.

Faulty wiring can be diagnosed by disconnecting the pump and checking the voltage and continuity on the wiring to the pump.

Corrosion on your pump terminals can indicate water leaks. If you see evidence of corrosion on your wiring or terminals, you should check the condition of the mechanical seal on the pump also.

If you have checked the wiring and terminals of your spa pump and there is a good electrical connection, but your pump keeps turning off, then the motor may be worn and need replacing.

Please note this information is provided for reference only. We recommend all electrical work should be carried out by a licensed electrician.

Why won't my spa pump turn on?

If your spa pump does not turn on altogether, this can be caused be either an electrical fault to your entire spa system, or a fault in the pump itself.

To diagnose this, first check if the control panel / touch pad on your spa shows lights on it. If there are no lights on your control panel or touch pad, then this shows a power issue to the whole spa.

Flip off the main circuit breaker for your spa, then disconnect power to your spa pump. Now flip on the breaker and see if your control panel turns on or your touch pad lights up. If it does, then you may have isolated the issue to an electrical fault in your spa pump.

Flip off the main circuit again and reconnect the spa pump. Turn the main circuit back on and attempt to turn your pump on. If this trips the circuit breaker then this most likely indicates that your pump has an electrical fault in it. This will need to be repaired by a qualified technician or electrician or replaced.

Please note this information is provided for reference only. We recommend all electrical work should be carried out by a licensed electrician.

How do I reset my spa pump? (Bleed airlock)

If you turn your spa on and see an error message on your controller screen, this may be caused by an airlock in your pump.

  1. Turn off the main power supply to your spa.
  2. Wait 15 mins to allow the element to cool down
  3. Undo the cabinet panel and remove this panel
  4. Locate the circulation pump
  5. Loosen the barrel union on the pump (at right angles to the spa) by turning it anticlockwise.
  6. When you see water dribbling out you’ll know that air has escaped.
  7. Re-tighten the union up by turning clockwise
  8. Ensure all T-Junction valves are in the up position to allow water through
  9. Turn the power back on.

How much does it cost to replace my spa pump?

As a general rule, a spa circulation pump will cost around $300-$400 to replace. Booster pumps are more powerful and will cost more to replace - up to $1,200 or even more if your pump is an uncommon model.

Do I have to drain my spa to change the pump?

No, it is not essential to drain your spa in order to change your pump, although if your water is coming up on 3 months old, you may want to take the opportunity to change your water.

If your water is still in good condition, there are a couple of techniques you can use to change your spa pump without draining your spa.

The first method is to use a cork to block the inlet and outlet pipes on your spa pump. You’ll need a couple of corks that match the diameter of your inlet and outlets on your spa pump. In many cases, this diameter will be 40mm or 50mm.

Have the corks all ready, right beside the pump, then disconnect the inlet pipe from your pump and quickly place the cork into the hose. You may want to use some duct tape to hold the cork into the hose so it doesn’t pop out.

Now it’s time to disconnect the hose on the outlet end of the pump. (Doing it in this order, will enable the non-return valve to seal the inlet end of the pump, while you’re disconnecting the outlet end) Once you’ve disconnected the outlet hose, place the cork into the hose and again hold it in place with some duct tape.

If you can’t find corks the right size, you can also use a couple of pairs of vice grips / locking pliers. To do this, fold the end of each hose over and use the vice grips to clamp the end of the hose.

You will probably spill a few drops of water, but if you’re careful, it won’t be a substantial amount.

How do I troubleshoot a faulty air switch in my spa?

Some components connected to the air switch can fail from time to time. The most common failure is in the air tube which runs from the button in your spa to the pump. Because it is a tiny tube, it develops pits that can eventually become holes so the tubing perishes and the air escapes.

If you push the button and it stays in, then the bellows may be faulty in the switch. If it works intermittently, then the fault is probably the air tube.

You may not need to replace the whole pump, you might just need to purchase $8 worth of tubing instead of shelling out up to $800 for a new pump!

Got more questions?

Talk to us, or email us your spa questions and we'll be happy to help!

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