Max-e-therm Fenwall or Control Board

dielseman

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Jul 1, 2017
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I am having issues getting my max e therm to ignite. Two people have diagnosed the heater and of course I got two different resolutions. One suggests the fenwall icm. The other suggest replacing the control board.

The gas is fine, igniter is warm. The error code I receive is three flashing lights on the fenwall.

Do I replace the fenwall or ICM? How do I know which one to replace?
 
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Fenwal is the manufacturer name on the box of the ICM.
 
my bad I was told to replace the fenwall and the control panel. The control panel turns on so I don’t know which one is correct.
Have to know what diagnostic lead them to one conclusion or the other? Or was it just they did not know what failed so they start replacing parts.

Did they check the igniter condition?

Did the check gas pressures with a manometer?

What is the condition of the gas valve?

Did they check the flame sensing?

How far does the heater get into the ignition cycle?

Could be many things. They need to explain what leads them to their recommendations.
 
Have to know what diagnostic lead them to one conclusion or the other? Or was it just they did not know what failed so they start replacing parts.

Did they check the igniter condition?

Did the check gas pressures with a manometer?

What is the condition of the gas valve?

Did they check the flame sensing?

How far does the heater get into the ignition cycle?

Could be many things. They need to explain what leads them to their recommendations.
All of that was checked. The igniter is warm. Gas is fine. They said the ignition tries three times to start but won’t. After that it goes into a safety mode and shuts off.additionally the heater does not turn on when pushed on the aqua link. But just be powered on manually on the heater itself. The control panel on the outside that displays the heater temp does work though. So I’m not sure.
 
Can someone please help with this so I can determine which part to order? Is it the Fenwall ICM or the control board?
We have no idea from the information you presented.

The tech needed to describe where in the startup cycle he found it failed To know what needs replacement. There is a specific sequence of voltages and signals that the control board and ICM expect which can be measured and traced with the proper tools.

You need a tech to tell you why and if you want a second opinion get enough details to post it here.

A description of the startup sequence can be found in Pentair MasterTemp Heaters - Further Reading and in the Pentair Installation manual.

You may also have a flame sense error as described in Heater Flame Sensing - Further Reading
 
We have no idea from the information you presented.

The tech needed to describe where in the startup cycle he found it failed To know what needs replacement. There is a specific sequence of voltages and signals that the control board and ICM expect which can be measured and traced with the proper tools.

You need a tech to tell you why and if you want a second opinion get enough details to post it here.

A description of the startup sequence can be found in Pentair MasterTemp Heaters - Further Reading and in the Pentair Installation manual.

You may also have a flame sense error as described in Heater Flame Sensing - Further Reading
The tech said the fenwall needs to be because the heater is warming up properly but turns on/off. The ignition and gas are fine according to his diagnostics. He was able to wiggle some wires briefly that allowed the heater to turn on. However once those wires were loosened the fenwall flashed three lights.
 
The tech said the fenwall needs to be because the heater is warming up properly but turns on/off.
What sensor is turning the heater on and off?

The ignition and gas are fine according to his diagnostics.

How do we know his diagnostics are correct?

What were the static and dynamic gas pressures?

What is the resistance of the igniter?

What is the voltage to the igniter?

He was able to wiggle some wires briefly that allowed the heater to turn on.

What wires were wiggled?
However once those wires were loosened the fenwall flashed three lights.
Which wires?

Why can’t he fix the wire or plug that is loose instead of replacing the Fenwal?
 
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