How to Tell if Your Hot Tub Heater Element is Bad

Posted by

Element with calcium scale -

If your breaker is tripping or your hot tub isn’t heating, you may have a bad heater element. We’ll walk you through the steps to determine if the cause of your problem is the heater assembly, heater element or another hot tub component.


Before getting started, it’s important to shut off all power to the hot tub at the service panel.

Tripped Breaker

To test if a bad heater is causing your tripped breaker, you can disconnect the copper tabs (or wires) from the spa pack to the heater element.

Disconnect power to the heater

Once disconnected, turn the power back on. If the breaker stays on, you’ve determined that the heater is bad. Find a replacement heater element.

Hot Tub is Not Heating

If your breaker is not tripping but your hot tub still isn’t heating, testing voltage to the heater using a multi-meter will help determine the cause.

Testing voltage

240V Spas

With the spa on, test both of the leads on the element at the same time. If the meter is reading 240v, the element is the problem. If the meter is reading zero, the problem is with the circuit board.

120V Spas

With the spa on, test both of the leads on the element at the same time. If the meter is reading 120v, the element is the problem. If the meter is reading zero, the problem is with the circuit board.

Alternate Testing Method

Another way to test for a bad heater would be an OHMs test, which checks the resistance of the element. To do this, follow these steps:

  1. Turn off all power to the hot tub
  2. Disconnect the copper tabs (or wires) going to the heater element.
  3. Set the multi-meter to the OHM setting
  4. Test both leads on the heater element

If the multi-meter shows 9-14 OHMs, the element is likely not bad. If the meter shows open, or reads nothing, the element is bad.

Replacing a Bad Heater Element

Once you’ve determined that the heater element is bad, you now need to decide if you need to replace just the element, or the whole heater assembly.

If the heater assembly is more than a few years old, it is best practice to replace the whole heater. Over time, corrosion and scale can deteriorate the heater assembly.

Need help finding a replacement heater or heater element? Email us a photo.


  1. Hi Frank,
    Your heater element very likely is shorting, and needs to be replaced. Try testing the element for continuity to ground. Place one of your meter probes on one of the element terminals, and the other probe to the heater manifold (if the element is removed from the manifold, place the probe on the element sheath). You should find no continuity, though you probably will. If you have any questions while you’re working on it, give us a call and we’ll walk you through it.



  2. The breaker tripped a few times and now the blue “Ready Light “ is off.The hot tug has water movement and is staying at 96 degrees but no hotter. I replaced the heater 3 years ago with the Watkins 6 k no fault and it worked great. Is it the heater/ or sensor/ is three years the life of the heater.


  3. Hi Mike,
    The NoFault heaters are actually quite robust, and have a long lifespan. It’s more likely on an IQ2020 control system that the heater control board is causing the issue. The heater control board is probably not sending voltage out to the heater and should be.

    Double check the heater though, just to make sure it’s good, by testing resistance through the white and black wires. You should find 9Ω – 15Ω resistance. Next, check from the white wire to the green wire. You should find no continuity. If those things check out, the heater is good.

    When you’re ready to test, give us a call at 800-823-3638 and we’ll walk through the testing together.



  4. I’ve got a 2005 Solana TX. Temp has dropped to around 96 ish even though the control panel is set at 104. I’ve removed the filter and ran it without for a couple of days but the temp never increased. I get no continuity from the heater element to ground and if I’m reading my meter correctly, I get 14.3 ohms. I think the heating element is ok, do you agree? If it is, what could be the problem?


  5. Hi Dan,
    If those are the readings you’re getting on the heater, it is indeed good. The next step is to see if the heater is getting voltage. Measure across the two hot lines to get your reading. I suspect you’ll find zero volts, which means you’ve probably got a bad heater relay board. When you’re ready to check, give us a call at 800-823-3638 and we’ll go through it together.


  6. Thanx for the quick reply Brian… holds steady at 96ish, wouldn’t that mean that I have voltage….or at least some?


  7. Hi Dan,
    Not necessarily. Friction from the pumps running can keep the tub warm-ish. Give us a call and we’ll walk through it together and get you set up.


  8. Just prior to me finding this site, I drained the tub and removed the heater. At this point, I won’t do anything to it until late summer early fall. I will bookmark this site and make contact with you when I refill. Thanx Brian for the info….I’ll be in touch


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s