Harman keeps popping fuses

[N_Blueth]

My 52i keeps blowing fuses and because of the time of year I can't get a service guy in here to check it out. I tried running it in manual mode and it still blows a fuse, suggesting it's not the ignitor. Does anything else draw as much power as the ignitor? What are the odds the circuit board needs replacing?

 

[jzm2cc]

At what point in the heating cycle does it blow a fuse? 5, 10, 30 minutes after start? High convection blower or low?

Curious if it would blow fuse with convection blower off, this is second in line for current draw after igniter. Then auger motor or exhaust motor would be 3rd.

Try running in stove mode and manual with a low heat setting (like 2 or 3). This will keep convection fan off and see if fuse lives through this test.

 

[N_Blueth]

At what point in the heating cycle does it blow a fuse? 5, 10, 30 minutes after start? High convection blower or low?

Curious if it would blow fuse with convection blower off, this is second in line for current draw after igniter. Then auger motor or exhaust motor would be 3rd.

Try running in stove mode and manual with a low heat setting (like 2 or 3). This will keep convection fan off and see if fuse lives through this test.

It pops within the first 30 seconds so the blower never gets to full speed. I've only tried running it in room and stove temp set to low.

 

[jzm2cc]

I'd be tempted to unplug the igniter, auger motor, combustion and exh motors, then power it back up to see if fuse lives. Then connect exh motor, repeat, etc. See which devices blows fuse and narrow in on that circuit.

 

[N_Blueth]

I'd be tempted to unplug the igniter, auger motor, combustion and exh motors, then power it back up to see if fuse lives. Then connect exh motor, repeat, etc. See which devices blows fuse and narrow in on that circuit.

I was thinking the same thing. I can't unplug them from the panel, right? Will I have to pull the stove out and disconnect each item from behind?

 

[heat seeker]

Are the replacement fuses the correct type and amperage?

 

[N_Blueth]

Are the replacement fuses the correct type and amperage?

They are. 6A, 250v.

 

[jzm2cc]

Best to not disconnect from control board connector, unless you have a pin puller. Just trace wires from motors till you find their blade connections, mark them and unplug. Assume you'd have to undock stove from chimney framework during this process.

I've only had an old Accentra insert, never 52i.

 

[heat seeker]

They are. 6A, 250v.

But was the original, and replacements, fast- or slow-blow fuses.

 

[N_Blueth]

Best to not disconnect from control board connector, unless you have a pin puller. Just trace wires from motors till you find their blade connections, mark them and unplug. Assume you'd have to undock stove from chimney framework during this process.

I've only had an old Accentra insert, never 52i.

Ugh. The unit is only three years old so I'm fairly annoyed this is happening.

Thanks so much for the feedback. I'll run the diagnostic test and post an update with the results.

 

[N_Blueth]

But was the original, and replacements, fast- or slow-blow fuses.

Not sure what you mean by fast or slow blow. If you mean time, all took less than 30 seconds to pop. Or perhaps fast and slow blow fuses are types of fuses?

 

[heat seeker]

Not sure what you mean by fast or slow blow. If you mean time, all took less than 30 seconds to pop. Or perhaps fast and slow blow fuses are types of fuses?

Correct, they are a type of fuse. Slow blow fuses are typically used for motors, to withstand the startup current surge. This may or may not be your problem, but for one of these small motors to blow a 6 amp fuse, it would have to be in bad shape. Do all of the motors reach their proper speed before the fuse blows?
I just reread post #3 - it shouldn't take 30 seconds to reach full speed. I'd start looking at that motor.

 

[heat seeker]

I'd be tempted to unplug the igniter, auger motor, combustion and exh motors, then power it back up to see if fuse lives. Then connect exh motor, repeat, etc. See which devices blows fuse and narrow in on that circuit.

That is an excellent troubleshoot procedure!

 

[N_Blueth]

Correct, they are a type of fuse. Slow blow fuses are typically used for motors, to withstand the startup current surge. This may or may not be your problem, but for one of these small motors to blow a 6 amp fuse, it would have to be in bad shape. Do all of the motors reach their proper speed before the fuse blows?
I just reread post #3 - it shouldn't take 30 seconds to reach full speed. I'd start looking at that motor.

Will look in to making sure I have the correct fuse. This is great information, thank you.

 

[rickwai]

A watt meter like the "kill a watt" plug in on amazon would make trouble shooting much easier. I have a
AmWatt Appliance Load Tester
that I use to troubleshoot Harman inserts. When you first turn it on with Comb. fan on only it draws about 125w. When igniter and auger kick in it jumps to 450-485w depending on old or new igniter. You are pulling over 720 watts to blow a 6a fuse. If you put in manual mode and start stove it should be very obvious with a meter like this. Lowes and Home Depot used to carry them, definitely worth the $25. I use mine on every stove service call. I hook it up and can check igniter function and draw before I even start servicing the unit. That way customer can't say " it was fine before you got here!"

 

[N_Blueth]

Will look in to making sure I have the correct fuse. This is great information, thank you.

So I was using the wrong fuse. I was replacing it with fast blow fuses. I have the correct fuse now, but that still didn't explain why it blew the first time. I put in a fuse, turned it on then opened the door to listen and I heard the ignitor "sizzle" then the fuse popped again. Currently taking that out to replace but I mistakenly did not pull the wires out the front before disconnecting them. Spent the last three hours trying to fish them through the little holes in the burn pot. That sucked. Hopefully this is just an ignitor issue. This will be the third one in three years too.

 

[Peterfield]

What I always used to ask my kids was, what was the last thing we're doing before it happened. In this case, what was the last maintenenace action you did before this problem surfaced? Was the stove moved to clean behind it? Were you cleaning under the burn pot and maybe hit the igniter or creased a wire? Hopefully retracing your steps, which you probably already did, might help and it also might get a response for a forum member that did the same thing. Good luck.

 

[N_Blueth]

My 52i keeps blowing fuses and because of the time of year I can't get a service guy in here to check it out. I tried running it in manual mode and it still blows a fuse, suggesting it's not the ignitor. Does anything else draw as much power as the ignitor? What are the odds the circuit board needs replacing?

We're up and running now. It was the ignitor after all.