A Common Repair Case We See in Older Infrared Saunas

A customer recently contacted us about an older Sauna Pro infrared sauna with a main control board labeled SKSA-120-EGH. The sauna stopped working suddenly, the front control panel stayed completely dark, and the fuse blew again as soon as the rocker switch was turned ON.

The customer had already replaced the SSR several months earlier, but the same type of electrical failure returned. Based on the symptoms, the issue was more likely inside the original control/power board or its internal low-voltage and output control circuits, not just the front display panel.

This is a typical example of why we usually recommend replacing the full control system on older infrared saunas instead of trying to repair one old circuit board or repeatedly replacing small individual parts.

Why the Front Control Panel Is Usually Not the Only Problem

When the front control panel does not light up, many sauna owners assume the control panel itself has failed.

Sometimes that is true. However, in many older infrared saunas, the front display panel receives low-voltage power from the main control board inside the power box. If the power board fails, the front panel may stay completely dark even if the panel itself is still good.

The front control panel is mainly the user interface. It sends commands, but it normally does not carry the main heater load. If the power board cannot supply power, communicate properly, or safely control the heater output, replacing only the front panel will usually not solve the problem.

Why Replacing One Old Circuit Board Is Usually Not the Best Repair

Many customers ask whether they can buy just one replacement board for an older infrared sauna. In most cases, that is not the best repair method.

1. Original Boards Are Often Discontinued

Many older sauna brands used control boards made by third-party factories. Over time, the sauna brand may go out of business, the original supplier may stop production, and the exact board model may no longer be available.

Even if the board has a model number such as SKSA-120-EGH, that does not mean a new direct replacement is still being produced.

A board that looks similar may also have different software, different wiring logic, different sensor values, or a different communication protocol.

2. The Control Panel and Power Board Must Match

Infrared saunas usually use a matched control system. The front control panel and the power output board are designed to work together through a specific cable, signal format, and software logic.

This means you usually cannot replace one random board and expect it to work correctly with the old control panel.

Even if the connector looks the same, the internal wiring and communication protocol may be different. A mismatched board can cause:

• No display
• No heating
• Incorrect temperature readings
• Relay clicking
• Repeated fuse failure
• Sensor errors
• Light or audio failure
• Damage to the new board

That is why we do not recommend guessing with individual circuit boards on older sauna systems.

3. One Failed Board Often Means the Whole System Is Aging

When a sauna is 10, 15, or 20 years old, the failure is often not limited to one visible part.

Inside the control box, several components may age at the same time:

• Relays
• Capacitors
• Low-voltage power supply components
• Transformer or switching power supply section
• Fuse holders
• Terminal blocks
• SSR control circuit
• Temperature sensor circuit
• Display communication circuit
• Connectors and wiring

Replacing one component may restore operation for a short time, but another part of the old board can fail later.

4. A Blown Fuse Can Indicate a Deeper Electrical Fault

A fuse is a protection device. If it blows immediately when the sauna is turned on, it is usually reacting to an overload, short, or internal failure.

Possible causes include:

• Shorted component on the main board
• Failed low-voltage power supply
• Damaged relay control circuit
• Faulty SSR drive circuit
• Internal board failure
• Wiring fault connected to the control box
• Heater output circuit problem

Because the front control panel depends on the main board for power and communication, a dark display does not always mean the display itself is the only failed part.

Why We Recommend Replacing the Full Control System

For older infrared saunas, the most reliable repair is usually to replace the complete control system, especially:

• A new digital control panel
• A new power output box

This repair method removes much of the uncertainty.

Instead of trying to make a new circuit board work with an old control panel, the sauna receives a new matched control system designed to work together.

Benefits of Replacing the Control Panel and Power Box Together

More Reliable Repair

A full control system replacement avoids relying on old, partially failed electronics. The new control panel and power box are designed as a matched set, which improves reliability.

Better Compatibility

Universal sauna control kits are designed to replace many older infrared sauna control systems. In many cases, the existing heater panels can still be used as long as the voltage and total wattage are compatible.

Safer Electrical Operation

Older boards may have aged relays, loose terminals, weak solder joints, or unstable low-voltage circuits. Replacing the full system helps reduce the risk of repeated fuse failures, relay clicking, overheating, or unstable heater control.

Easier Troubleshooting

With a new control system, the control logic is complete and consistent. If one heater panel does not work after installation, the issue can be isolated more easily by checking the heater, cable, or output port.

Longer Service Life

Instead of repairing one discontinued old circuit board, replacing the control system gives the sauna a much better chance of working reliably for years.

Can the Original Heater Panels Still Be Used?

In many cases, yes.

Most infrared heater panels are simple heating elements. If the heater panels are still in good condition and the resistance readings are normal, they can often be reused with a new control system.

Before choosing a replacement controller, it is important to confirm:

• Sauna voltage: 120V or 240V
• Total heater wattage
• Number of heater panels
• Heater connector type
• Original control panel location
• Power box location
• Whether the sauna has lights, speakers, or color therapy
• Temperature sensor type and location

For safety, all wiring should be checked carefully before installation. If there is any sign of melted wiring, loose terminals, burned connectors, or water damage, those issues must be corrected before using the sauna again.

Why Board-Level Repair Is Not Recommended for Most Customers

Some electronics technicians may be able to repair a failed circuit board by replacing capacitors, relays, resistors, or power supply components.

However, this is usually not practical for most sauna owners.

Board-level repair has several disadvantages:

• It requires electrical testing skills.
• It may not identify all aging components.
• The same board may fail again later.
• Replacement components may not match the original design.
• The control panel may still have communication issues.
• The repair may not restore safe heater control.
• There is usually no long-term compatibility guarantee.

For this reason, we normally recommend replacing the complete control system instead of repairing one old board.

When Is a Full Control System Replacement the Better Choice?

A full control system replacement is usually the better repair direction when an older infrared sauna has symptoms such as:

• No power on the control panel
• Blown fuse
• Fuse blows again after replacement
• Clicking relay
• Flashing lights
• Sauna not heating
• Random shutdown
• Temperature control failure
• Power board failure

For older infrared saunas, the best repair is usually not replacing one small circuit board or repeatedly replacing one small part. The better long-term solution is to replace the complete control system: control panel + power output box.

This gives the sauna a new matched electronic system while allowing the existing sauna cabin and heater panels to continue being used.

Looking for Sauna Repair Parts?

If your sauna has a dark control panel, blown fuse, clicking relay, flashing lights, or no-heat issue, send us photos before ordering. We can help identify whether a full control system replacement is the right solution.

Please send clear photos of:

• The front control panel
• The main power/control box
• The circuit board label
• The heater connections
• The sauna voltage label
• The inside of the sauna

Text: +1 702-348-0250

Email: support@saunapartsworld.com

Frequently Asked Questions