The way a power vent water heater works is that when you switch it on, it energizes the blower. After it does that, the blower starts and the pressure switch closes on a faller pressure. Once the switches closes, the heater starts an ignition sequence. This means that an igniter is going to warm up, which takes about 17 seconds.
The next thing that will happen is that the gas valve will open up and once this happens, the gas enters the combustion chamber and you have about four seconds to see the flame. The flame then lights up the burner and then the gas burner starts to heat the water. The burner then goes off and the blower continues to run to get the combustion product out and the water heater goes into standby.
Error Code Occurrence
The above mentioned sequence of operations continues when the heater is working fine. At any given moment, if the sequence of operation stops, that is when you are going to display a code. Understanding the sequence is therefore important as it helps you understand the troubleshooting process.
The first common problem leads to three blinking lights, or in other words, an error code three. Once you get three flashes on the controller, or you get a warm light lit up, along with triangle and the C light lit up, then you can conclude that the air pressure switch did not close. This means that the heater did not go on with the sequence.
In the sequence of operations, the point when the blower was suppose to kick on, it never sees the switch close. In this issue, the first thing that you need to check is whether the blower motor is running. However, if you have the older style valve, the blower should be running continuously. If it is not running, then you have another problem.
On the newer heater, it will allow the blower to run for 30 seconds before anything kicks off. If it is the new kind of gas valve, then you have to cycle power off and turn it back on to see if the blower starts. If the blower still does not kick on, then you have to change the blower capacitor on the valve. It is very rare but capacitors can fail.
During the winters, one of the most common issues that you can face with the power vent water heater is ice. Since you need to usually keep them in an open space for ventilation, these heaters will sometimes get iced out and lose their capability to heat. In this instance, you need to seek professional help to winterize your heater and extract ice from it. This will help keep in running throughout the freezing temperatures of the winter.
The power vent water heater troubleshooting can be very complex and diverse. Error codes can sometimes be pointing to multiple signals. In this instance, you have to seek help from technicians that know their way around power vent water heaters.