Honeywell Water Heater High Temperature Shutdown

Enjoying the ‘aha’ moment in shower on a chilly morning is impossible without a properly functioning water heater. 

Thousands are there to blame if your water heater doesn’t function properly. High Temperature Shutdown mode is one of those reasons that cause the unit to not produce hot water. 

But do you know what the high temp shutdown actually is? How to override or reset this water heater status and get hot water? 

If the answer is no, this guide on Honeywell Water Heater High Temperature Shutdown will answer those questions. 

So, continue to read till the end.

Table of Contents

• What Does High Temperature Shutdown Mean On A Hot Water Heater? 
• Honeywell Water Heater High Temperature Shutdown [5 Easy Solutions]
  • 01. Setting The Temperature Too High 
  • 02. Defective Thermostat
  • 03. Restricted Pressure Relief Valve 
  • 04. It’s Dirty Burner, Not The Heating Element
  • 05. There’s Scale Buildup
• How To Reset ‘High Temperature Shutdown’ Error On Honeywell?
• FAQs 
• End-Note

What Does High Temperature Shutdown Mean On A Hot Water Heater?

High Temperature Shutdown means your hot water heater goes into the shut-off mode due to excessively hot water. 

Typically, the status light will blink 4 times when your water heater goes into the High Temperature Shutdown mode. However, you can’t see the flashing light when the water heater goes into the error. 

It indicates the pilot light gets extinguished and it fails to produce the required flame to operate the thermopile. 

You can only see the status light to come on when you relight the pilot. 

Now, let’s get back to the point. 

Several reasons like incorrect temperature setting, bad thermostat, and mineral build are responsible for the unit to get into the High Temp Shutdown mode. 

In the next chapter, I will describe each of those culprits in detail. So, keep scrolling. 

Honeywell Water Heater High Temperature Shutdown [5 Easy Solutions]

Let’s discover the common reasons that are responsible for the water heater to go into the High Temp Shutdown mode. 

01. Setting The Temperature Too High

A slightest movement of the gas control knob on the gas valve can make a big difference! This is so true for a water heater and its temperature. 

After a routine maintenance, it’s not impossible for you to turn the temperature knob to the highest setting accidentally. 

Needless to say, the water temperature will climb above the safety limit when that occurs. 

How To Fix: 

Fortunately, you don’t need to take any corrective action- except turning down the gas control knob. 

Yes, it’s exactly what you should do. 

Just move the gas control knob to your desired temperature setting. Ensure the temperature setpoint isn’t exceeding over 120-degree F. 

Otherwise, it will burn your skin if you set the temperature to the Very Hot setting.

02. Defective Thermostat

A faulty thermostat is the next culprit that causes the unit to overheat the water. 

Every water heater, either a gas or electric, has a thermostat to monitor the temperature. If it’s at fault, it will send wrong signals to other components like thermocouple and pilot light. 

Consequently, it measures the water temperature intermittently.  

Unlike electric hot water heaters, the gas water heater with Honeywell Control Valve has an invisible thermostat.

Yes, it’s invisible because you can’t see it unless you remove the gas control valve from the unit. ^[1] The gas valve has a temperature probe on the back. It works in tandem with the temperature setting on top of the valve to light the burner and raise temperature. 

When it gets damaged, it may heat the water excessively. 

How To Fix: 

Either you can call a technician or do it yourself to replace the thermostat. It completely depends on how comfortable you are with the gas appliance. 

If you allow me to decide it for you, I would highly recommend you call a professional to deal with this task.  

However, if you choose the DIY option, I recommend you watch this tutorial before jumping into the work: 

03. Restricted Pressure Relief Valve

A gas water heater works by using the fire, steam, and pressure to bring the water temperature to the setting you choose. But do you know where all the pressure goes afterwards? 

It’s the pressure relief valve that releases the excessive pressure out of the unit. This part, undoubtedly, is the most crucial part of the unit. It prevents the unit from exploding due to excessive pressure buildup. 

If somehow the pressure relief valve gets clogged, it fails to dissipate the excessive pressure. As a result, the pressure inside the tank keeps building and it overheats the water. 

How To Fix: 

You should turn off your gas water heater right off the bat if you suspect the pressure relief valve is the culprit. Then, call a professional to deal with the issue. 

I never allow you to resolve the pressure relief valve issue by yourself as it requires you to follow & complete some complicated steps. 

04. It’s Dirty Burner, Not The Heating Element

When it comes to High Temperature Shutdown, most articles on the web blame the heating element.

Of course, their claim is valid if it’s electric hot water. But for a water heater with Honeywell Gas Control Valve, it’s misleading. It’s because a gas water heater doesn’t come with a heating element; it has a burner instead.^[2] 

If the burner gets dirty, your water heater will not function properly. In this case, cleaning the burner is a must. 

How To Fix: 

Follow the below steps I described to clean the burner: 

• Shut the gas supply off to the unit and turn the gas control knob to Off position.

• Detach the thermopile wire and the igniter wire from the gas control valve. Then, use an adjustable wrench to unscrew the pilot tube. 

• Once you disconnect every connection from the gas control valve, remove the bottom access panel. 

• Unscrew the manifold door and pull out the burner assembly. 

• Clean the burner with a scrubbing brush to remove rust and corrosion buildups. 

• Don’t forget to vacuum up the burner chamber with a vacuum attached with an extension brush. 

• After cleaning the burner, reinstall the burner assembly into the burner chamber and replace the burner manifold door. 

• Connect everything that leads into the gas control valve. 

• Finally, turn on the gas supply to the unit.

05. There’s Scale Buildup

Scale formation in the piping and on the bottom of the tank is not an unusual hot water heater issue. You will surely encounter this issue sooner or later. 

If you ask me how quickly or lately the mineral or deposits form, I will say in response- it depends on where you live and how hard the water is in your area. 

Because of scale formation, it will be challenging for the unit to heat the water properly. In the worst case, it may even overheat the water and lead the unit to go into the ‘High Temp Shutdown’ mode. 

How To Fix: 

It’s recommended to flush the unit annually to let the hot water perform properly. If you live in a hard water area, you should flush the water heater every six months. 

If you are handy, you can try to flush the piping and the water tank to remove the sediment buildups. Otherwise, it will be better to leave this maintenance task for professionals. 

How To Reset ‘High Temperature Shutdown’ Error On Honeywell?

Follow the below step-by-step procedure to reset the ‘High Temperature Shutdown’ mode: 

1. Relight the pilot. In this case, complete the following steps to relight the pilot successfully: 

• Turn the gas control knob to the off position and leave the unit in that condition for five minutes. It will let the unburned gas clear out. 
• Move the temperature control knob to Pilot and hold it all the way in. 
• Now, keep depressing the piezo igniter button rapidly while holding down the gas control knob at the same time. 
• Repeat this until the status light comes on. Once the pilot light comes on, you can see the status light is blinking 4 times, which indicates the unit goes into High Temp Shutdown. 

2. Once the pilot light is on, turn the gas control knob to Very Hot and let the knob stay there for 10 seconds. 

3. Afterward, move the gas control knob to Hot position and count 10 seconds. 

4. Set the temperature control knob from Hot to Pilot and count another 10 seconds. After a few seconds, you can hear the burner coming on. It indicates you override the ‘High Temp Shutdown’ error successfully. 

5. Finally, set the control knob to your desired temperature setting to heat the water. 

FAQs

How do you turn off the Honeywell Water Heater?

It’s pretty simple to turn off your Honeywell Water Heater. Just set the gas control knob to Off position, which will shut down the unit. 

How can I adjust the temperature on a Honeywell Water Heater?

Adjusting the temperature on a Honeywell Water Heater is simple. The temperature setting on the gas control valve will help you customize the water temperature. Honeywell Gas Control Valve has three temp settings: 

• Hot 
• A B C
• Very Hot

Just set the gas control knob to your desired setting and leave the unit. 

End-Note

Your water heater goes into the High Temp Shutdown mode due to overheating issues. Luckily, I already mentioned those culprits that cause the unit to overheat the water. 

Firstly, look for those caveats behind the overheating problem and fix them. Finally, override the High Temperature Shutdown mode by following the steps I broke down. 

I am 100% sure it will get your water heater out of the High Temp Shutdown mode and deliver hot water to give you comfort. 

Read Also:

• Honeywell Water Heater Status Light Codes