Features of an Efficient Spa Heater System

The "hot" in "hot tub" comes down to having a built-in, efficient heating system that goes above and beyond the hot water pushed into the average bathtub by your basement heater. Working in concert with the spa pumps, the heater is the component that differentiates a true spa experience from a simple warm bath.

Whether you're looking for a complete standalone heater or a new replacement heater element for your flow-through unit, choosing the right spa part for this particular job is the perfect way to boost the luxury factor and energy savings.

Hot Tub Heater Assemblies 

The assemblies most often have a flow-through design for continuously heating water as it passes through. They are mounted in-line between your water source and feed heated water to your spa's external jets. They often have variable voltage/wattage and some, but not all, come complete with the control systems, heating elements, pressure switches, hi-limits and mounting equipment required for full functionality. Balboa spa heaters are a popular choice. 

Heater Elements 

Spa heater elements are the key component to efficiently heating your water. The core of the design is a heating coil, surrounded by a corrosion-resistant alloy to keep the sensitive filament within from exposure to moisture. Think of the design of the classic light bulb, except much, much stronger! The sensitive, conductive core materials have varying lifespans, and should be the first component looked at in an underperforming heater.


Spa heater gaskets seal off the connection between the assembly and the water entry/exit points. A low quality gasket will eventually crack or even melt under pressure, while the leading brands recommended by professionals will last far longer if installed properly. If you notice leakage around the unit, you should likely consider an upgrade.

Pressure and Flow Switches 

These protect both your components and your guests from low water pressure passing through the assembly. Low water pressure can quickly lead to much higher temperatures than intended. If low pressure conditions are detected, the pressure switch sends a signal to immediately stop operation. How important are hot tub pressure switches? Consider this: Many heating elements are capable of melting PVC, and with zero water flow, they become notable fire hazards.


Spa thermowells are the protective hardware that covers the sensors on and within your heater assembly. They’re often made of stainless steel or other metal bar stock, and they help ensure the sensitive components of your unit are protected from the effects of high temperatures and pressure. The health of your sensors depends on a properly installed and maintained thermowell.

Thermostat Sensors 

Hot tub t-stats, hi-limit and temp sensors monitor the conditions of your setup and send information to the control panel and assembly and other components, depending on the nature of your setup. They pass along important temperature data, send warning signals if the top safe limit is reached, and set target temperatures as needed.

At Wild West, we carry full heater assemblies as well as all of the components required to repair or replace an ailing model, from the most well-regarded spa brands around. We offer both natural gas and electric heater options for your hot tub spa or bath. If you’re looking for advice on which part or product is right for you, how to install it, or how to maintain it, contact our experienced staff.