Honeywell Hot Water Heater Status Light Blinking 3 Times [5 Easy Solutions]

Honeywell hot water heater status light blinking 3 times defines a stuck open draft pressure switch of the furnace. A pressure switch may be stuck open due to blocked exhaust vent or air intake, weak inducer fan, failure of inducer motor, and clogged condensate drain of the furnace. 

honeywell hot water heater status light blinking 3 times

Also, loose wiring connection, blocked or detached pressure switch hose, water collection in the hose or sometimes, the defective pressure switch is the culprit itself.

While troubleshooting the 3 blinking errors, you need to check for blockage in exhaust venting, inspect the switch housing, unclog the drain line and replace the damaged inducer assembly. Follow the below guide to get the details of troubleshooting for this error. 

Honeywell Hot Water Heater Status Light Blinking 3 Times [5 Easy Solutions]

The pressure switch of the furnace is a safety component located near the draft inducer motor. The motor runs and moves out the combustion gasses through the vents. 

The pressure switch senses negative pressure in order to suction gases out and to start ignition by closing the switch. If it fails, the switch will remain open and catch the 3 blinking error code. Read the below article to know the reason behind this and the corresponding solutions:

Note: You can also read how to fix the Honeywell water heater status light blinking 7 times

1. Blocked Exhaust Vent/Air Intake

The first most possible reason for the pressure switch to be stuck open is the blocked exhaust vent of the furnace. All water heaters are equipped with a venting system from where exhaust gases remove from the water heater to the outdoors. 

blocked exhaust vent/air intake

In order to function the heater properly, it needs a fresh air supply for combustion that is pulled by a vent pipe from the outdoors.

Anyway, after long wear and tear, debris like leaves, twigs, seeds, and small branches from nearby trees or creosote blocks the exhaust vent. There are some other common sources of vent blockage, including:

  • Soot buildup in the vent
  •  Damaged vent
  •  Corrosion/rusted-out vent
  • Rodents inside vent
  • Snow blocking vent

Blockage in the pipe prevents proper movement of gases from a furnace and leads to the heater overheating. It also prevents the inducer fan from creating negative pressure and causing the pressure switch to be stuck open. 

How To Clean Blocked Exhaust Vent Of Honeywell Water Heater

Follow the below steps to unblock your furnace’s exhaust vent:

  • In the first step, you have to find out the source of the blockage. Take a look at the air intake vent and exhaust vent outside of your home.
  • Once you have found the source of the blockage, start cleaning the blockages. Remove the stuck debris using tools.
  • You can use the vent cleaning brush to scrape off any buildup shoot from the vent’s interior walls.
  • Check out the vent cap as well. Replace the damaged vent cap and damaged/rusted portion of the vent.

2. Failure Of The Inducer Fan & Fan Motor

After the exhaust venting, the second most probable suspect behind the pressure switch stuck open is the inducer fan and fan motor. An inducer fan is used to check the proper airflow out of the furnace’s exhaust. 

inducer fan & fan motor

Anyway, the most common reasons for inducer fan and fan motor failure include:

  • The inducer motor is not starting or stuck by debris.  
  • Broken fan motor bearings
  • Obstacles in the fan blades
  • The low voltage supply to the inducer motor
  • Faulty wiring connection between the inducer motor and the control board
  • Burned out motor
  • Malfunctioning from the control board

If the motor is damaged, it fails to create the negative pressure required to close a pressure switch and leading to the blinking issue. Follow the below instruction to troubleshoot the failure of the inducer fan and fan motor.


  • First up, turn off the power connection to your furnace and shut off the gas supply.
  • Then, remove the panel to gain access to the inducer fan assembly.
  • First, look for any rattling or vibrating noise coming from your furnace’s inducer. For this, turn the power back to check what’s causing the vibrations and remove it.
  • Also, ensure all the screws on the inducer fan assembly are tightened.
  • Now, fix the stuck inducer motor. Remove the stuck debris from the fan blades and motor.
  • Then, spin the fan blades manually. 
  • If the fan along with the motor runs freely, be sure there have power issue going on with the motor. Measure the voltage of the motor and check out all the wiring connections to the control board.
  • Now, if you find all the wiring connections good but low voltage like 70 or 80VAC, check the control board. Replace the control board.
  • In some cases, you will need to replace the defective inducer fan assembly. 

3. Clogged Condensate Drainage System

A blocked condensate drain is one of the leading reasons for the pressure switch issue. Almost all the heating equipment relies on a condensate drain line to keep the system going. 

clean the water flow

If the furnace drainage system is clogged with debris, it causes a backup in the blower fan housing, which leads to the furnace pressure switch is stuck open. Also, blockage in the drain line causes water buildup in the inducer fan housing. 

If the drain line is blocked by debris or frozen condensate, the pressure switch may open and prevent ignition. Anyway, this time we will check the drainage system of the furnace.


  • First, turn off the gas supply to the water heater.
  • Locate the condensate drain line of your furnace. It is a single drain tube running out of your furnace. 
  • Inspect the line for any type of blockages and damages.
  • There are several ways to unclog the drain line. Check out the drain valve as well. You may use wet/dry vacuum suction or a wire coat hanger for cleaning.
  • Move the wire in the circular motion inside of the line and loose the stuck debris.
  • Clean the line until the water begins to flow out of the tank.
  • Don’t forget to remove any excess water from the drain pan and inducer fan housing.
  • Contact any professional plumber for this purpose. 

4. Blocked Or Detached Pressure Switch Hose

If the above troubleshoots fail to erase the error codes, a damaged pressure switch hose can be the culprit. The pressure switch is connected to the exhaust vent through the switch hose. 

It is used to detect if the inducer motor is working properly. In the case of damaged, cracked, or disconnected hose, the switch hose creates obstacles, fails to detect a negative pressure from the pressure switch, and leads to the switch being stuck open.


  • First, locate the pressure switch of your furnace.
  • If your furnace is two-stage furnace, you will see two pressure switches that you need to check. 
  • Check out the switch hose. If it is disconnected, connect it tightly to the port.
  • Before that, look for any type of stuck debris in it. Also, there may have moisture build-up inside the hoses.
  • Clean the hose and empty out any water from the hoses.
  • Replace the cracked or damaged switch hose.
  • All that will ensure the perfect operation of the pressure switch.

5. Broken Draft Pressure Switch

Last but not the least, due to a broken or malfunctioning switch, the furnace pressure switch is stuck open and the Honeywell water heater 3 flashes error will occur. 

water heater pressure switch

Now, you have to check if the pressure switch itself is in good condition. To do this, you can test the continuity across switch terminals. Here are the needed procedures:

How To Test Pressure Switch On Water Heater

To test for continuity across the pressure switch:

test pressure switch on water heater
  • Turn off the power supply of the heater.
  • Remove the access panel of the furnace and locate the pressure switch.
  • Take a multi-meter and connect the two terminals on the pressure switch with the leads.
  • If the furnace is off, switch terminals should be open, and you will see OL on your multi-meter.
  • Now turn on the heater and set the thermostat in the “Heat Mode.”
  • Check the switch in the previous ways. This time, you will find a low amount of resistance or will beep if it is in continuity mode.
  • You can test the voltage of the switch as well. This will show between 24-28 volts when the thermostat to “OFF” mode. This indicates that the pressure switch is open.
  • In the case of “HEAT” mode, between 0 volts which clarifies that the switch is closed
  • If the switch fails to pass the test, be sure it is defective, and you need to replace it.
  • Whenever you’re dealing with electrical components, it will be better to consult with a professional. 

How To Change A Pressure Switch On A Hot Water Heater

Replacing the defective pressure switch is not a hard deal as long as you know the correct method. Follow the below steps to replace the bad pressure switch from your furnace effectively:

  • First up, turn off the power to your furnace.
  • Remove the access panel to gain access to the switch.
  • Disconnect the hose from the port.
  • Unscrew the connected screws to remove the pressure switch.
  • Remove the old pressure switch and install the new pressure switch by reversing the above steps.
  • Connect the hoses to the new pressure switch. Make sure to connect the hose to the negative port (–) on the pressure switch.
  • Attach the wires tightly and reconnect the access panel to your furnace.
  • Turn the power back on and set your thermostat to the “HEAT” mode.


How do I reset my Honeywell hot water heater?

 To reset your water heater, switch the pilot dialer to “very hot” for 10 seconds. Then turn the knob to “hot” for 10 seconds and to “pilot” for 10 seconds. 

Why does my hot water heater keep going out?

A dirty thermocouple is a leading reason for water heater keeps going out. A clogged pilot tube, kinked thermocouple, and faulty main control valves are also highly responsible for this. 

Wrapping Thoughts:

To the ending point of the article, now you know all the responsive factors for occurring  3 blinking error code on the Honeywell water heater. 

Troubleshooting this error will not seem so hard as long as you will follow out above well-proven guide on Honeywell water heater status light codes

Still, if you face any troubles while fixing the issue, feel free to ask us through comments. We are always ready for your assistance.

About William

William is the founder of He has real life practical skills in fixing smoker & heating appliance issues. He loves to share his knowledge & helps others in fixing their appliances & saving their money. William firmly believes that anyone can repair his or her unit with the correct guidance & knowledge. See more at about us.

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