Hot Tub Overheating – OH, OHH, OHS Error Codes


Hot tub overheating codes (OH, OHH, and OHS) serves to notify you that the water temperature is unsafe. If the water in your hot tub is between 108°F – 118°F, it will automatically turn on the emergency cool down. The heater is turned off, and the blower and circulation pumps start working to help the water reach the ideal temperature.

This issue is very common, especially during hot weather. So, there’s no need to panic if you see the OH code on the hot tub. In this article, we will get you through everything you need to know about this problem as well as show you how to fix it.

What Causes Hot Tub Overheating?

The most common thing which causes the hot tub to overheat is low water flow (FLO, FLOW, LF). This leads to the appearance of the OH code on the hot tub. Besides, you could receive the OHH or OHS error.

The heater gets hotter if the water flow is not fast enough. Consequently, water in the hot tub becomes hotter. Eventually, the temperature sensors will shut it down to prevent more serious problems. Low water flow can be caused by:

  • Dirty hot tub filter cartridges
  • An obstructed drain cover or a blocked pipe
  • Closed or clogged jets or valves
  • Low levels of water in the hot tub

However, if water flow is fine, there might be a problem with switches or the thermostat. They can sometimes become too sensitive or have problems with calibration. Digital hot tubs come with electronic sensors that last longer than regular mechanical switches. But, high limit sensors, circuit boards, and temperature sensors on modern tubs are likely to have some difficulty in operating overtime.

The problems with water flow can be easily fixed in most cases. After doing this, the hot tub will typically cool down, and reset on its own. However, you will need to restart certain hot tubs. If your hot tub does not have digital controls, this means you may have to reset the high limit switch manually.

You might also like: Why My Hot Tub Breaker Trips?

How to Fix the OH Code on Hot Tub


Fixing the overheating problem is fairly easy, but there are many different causes. Identifying the cause is the first step to a solution. The most common ones are:

  1. The simplest cause of overheating is the water temperature set too high. To solve the hot tub overheating problems, try adjusting the temperature to 98°F. Also, bear in mind that your tub may show a higher temperature due to warmer outdoor conditions.
  2. Another cause may be wrong filter cycle duration settings. You need to check how often your hot tub should be filtered. Running pumps generate heat so this process can significantly increase the water temperature. If your hot tub filter settings are too high, it means the pump is running too often. This can lead to the appearance of the OH code on the hot tub. To fix this, adjust the settings to run early in the morning and late in the afternoon. This is when it is coldest outside, so it may stop overheating. Also, open the air controls. The air will help cool down the cabinet.
  3. Weather and sun exposure can also cause hot tub overheating. Your hot tub will dissipate less heat if it is placed in a very muggy and hot atmosphere. Also, overheating is much easier if your hot tub is located in an area with little to no shade. To fix this problem, drain some water and then add colder fresh water instead. When doing this, be very careful to maintain the water level above the filters. Your pump should never be running dry! Some hot tubs are equipped with a reflective side to the heat stays inside the cabinet. If you move it, the heat will slowly start to dissipate.

In case you have tried all of the above-mentioned solutions and you are still getting no results, contact a professional, and schedule an appointment. There might be a mechanical problem that you are not able to solve on your own. Bear in mind you should always seek help from official dealers and technicians.


Q: How Do I Cool Down My Hot Tub?


You can cool your hot tub down in many ways, such as: lowering the temperature to 98°, changing the filter duration settings, opening the air controls, draining some water from the hot tub and then adding fresh water. Also, if your hot tub comes with a reflective side, you should try moving it. Also, pay special attention to water flow and check whether anything is causing obstruction.

However, if none of these methods works, there might be a more serious problem with the hot tub. In that case, contact a professional or official customer service. They will typically solve the problem as soon as possible, and you will be able to enjoy climbing up the hot tub steps in no time.

Q: How Hot Is Too Hot For a Hot Tub?


Any temperature over 104 degrees Fahrenheit is considered too hot for a hot tub. Generally, the water temperature should be around 100 degrees Fahrenheit in order not to cause problems in healthy adults.

However, special attention should be paid to water temperature if young children are using the hot tub. You should always check how the children are feeling and behaving upon entering the tub.

Globo Surf Overview

Your hot tub will automatically get into the cool down mode once the water temperature reaches 108 °F. You may be notified of the OH, OHH, or OHS error. Cooling the hot tub down is not complicated, and there are many different ways to do it.

You could try checking the water flow, lowering the temperature, changing the filtration settings, opening the air controls, and adding fresh water. In case nothing helps, contact a technician or official customer service of your hot tub.

More Watergear Hot Tube Guides:


  1. How to Fix Hot Tub Overheating