A Little Bit About Your Spa Heater

One could argue that the hot tub heater is the most important part of your spa. No one wants to sit in freezing cold water unless it is 100 degrees outside and I’m sure that is not what you intended to do with your spa when you purchased it. Also if your heater is not functioning properly it can leave you with a frozen expensive mess in cold winter months. We are going to take your through the basics of troubleshooting, spa heater parts, and tips to extend the life of your heater.

Section 1- Trouble Shooting

Now let’s first cover the basics, if you go to get in to your hot tub and what you expected to be a warm relaxing oasis happens to be more like an ice skating rink, there are a few things to check first:

Is there electricity flowing to your hot tub? Check your control panel and make sure the spa is on. Check the GFCI (a breaker built into a power outlet or housed in a separate box), your high limit, and your home circuit breaker or fuse box. If your GFCI is tripped, it could mean that your heater element is to blame. If your hi-limit is tripped it could mean that you are not getting water flow and it is time to check on your pump. If nothing is tripped and your still have no power we would recommend that you at this point call a spa service technician or an electrician.

Now that the basics are covered and it is determined that you are getting electricity to the tub there are a few other things you can look for. If you are getting power, the next thing is to see if the spa itself is working. Check your control panel for common error readings like FLO or OH. A FLO error reading means there is a problem with your water flow. An OH is an over-heated reading. If your water is over-heating chances are you could have a problem with your thermostat or high-limit switch. If you have a water flow problem, you need to take a look at your pump. If you are not getting these errors and you have water flowing and your heat light is on, it is time to check your heater.

After finding your hot tub’s heater assembly (usually a metal tube with a heating element and other electrical components inside) check for rust and corrosion, if you find these present it is probably time to replace your entire heater assembly.

If the heater housing assembly appears to be in working order and free of rust and corrosion, you can try replacing the heater element. We recommend doing this only if you are very handy as it can be somewhat difficult and dangerous, if you need help please contact a professional spa technician.

Section 2- Heater Parts and Stuff

If you are like me (unhandy), when you first open up your spa and take a look inside at all the parts and try to figure out what each one does it can be a little overwhelming. Here we will provide a little glossary when it comes to the parts of your spa heater.

Heater Assembly- Heater assemblies come in various forms depending on the manufacturer of your hot tub, but the most common is a stainless steel tube that houses the heater element. The housing exchanges heat produced by the element as the water flows through it. Often the assembly will also integrate the high-limit and the thermostat.

Heater Element- The heater element is just what is name says, it is the element which produces the heat to warm your water. Heater Elements are similar to a light bulb in that after so much use they can burn out. Heater elements can also be the victim of calcium build up and corrosion if the spas chemicals are not kept in check.

Thermostat- Consists of a rotating control for setting desired temperature level, and a capillary tube with bulb attached for remotely picking up the spa water temperature. The sensor bulb is often housed in a thermowell for protection. For proper operation, the thermostat must be located in the spa plumbing between the suction point and the heater, NEVER after the heater.

High-Limit is a safety switch which is usually closed until there is a problem with excessive heat. Once the temperature reaches its certain set point, it latches open, breaking the circuit. This prevents the heater from meltdown if there is an equipment failure. It must be manually reset by pressing its button, after the temperature condition has returned to normal. A tripped high limit causes power to be cut before the fuse, immediately shutting down both your pump and heater.

Pressure Switch- This is a safety device that shuts off power to the spa heater circuit if the flow of water is interrupted. It remains closed during normal operation but will pop open if the pump fails, preventing the burn up of the heater if water is not flowing.

 

Section 3- Extend the Life of your Spa Heater

The number one thing you can do to extend the life of your spa heater is maintain proper chemical levels in your hot tub water, especially pH. Chemical levels that are not balanced will cause scale or calcium build up and corrosion especially on your heater element. Buying an element made of titanium rather than a standard element can also help.

Your spa should also never be set at a temperature higher than 104 degrees Fahrenheit or 40 degrees Celsius. Temperatures higher than this can not only negatively affect your equipment but can be dangerous for the people getting into the hot tub also.