US Stove 5660 Blows 250 volt 8 amp fuse as soon as I hit the power button

Hi I have a US Stove 5660 pellet stove. Recently after cleaning it I started it and it shut off and then had zero power. I checked the control panel and the circuit board was fried. There was an obvious area that got hot and melted the soldered tape that made up a circuit. Everything seemed fine with the wiring, so I assumed it was just from age (stove is 15 years old). I installed a new control board, plugged in the stove and the red power light came on, then hit the power button and within seconds it lost power. I checked the control board and the 250 volt 8 amp fuse was blown.

I’m in the process of getting a replacement fuse, but my question is what would cause this. The auger motor is brand new, I replaced it after I realized the circuit board was fried, (I had it with bearings and a new auger so I put them in)

When I test the resistance of the exhaust blower it is 6 OHMs the room blowers resistance is 3.6 OHMs. When I test the igniter’s resistance it’s open. At start up (I believe) only the exhaust blower, auger, and igniter receive power, the room blower doesn’t start until the stove is hot.

Do you think the exhaust blower with a resistance of 6 OHMs is causing the fuse to blow, or the igniter with an open circuit, or something else?

Any advice is appreciated, I plan on replacing the fuse and disconnecting the igniter and seeing if it happens, if it doesn’t I would think it has to be the exhaust blower, I just would rather not keep blowing the fuse on a $300 control board.

Hello
Usually in my experience the igniter blows the fuse and if good then it should read 50 ohms. You can disconnect the igniter and with a new fuse try the power button again.
If not I have seen the auger motor and the exhaust blower draw too much current. A better test than resistance for these motors is to use an Amp clamp on one of the motor wires and plug them into the AC wall outlet.
Using the Amp Clamp on the meter purchased at Home Depot below a Bad Igniter Triac on a Harman Circuit board was found. A new circuit board was installed and the current draw tested correctly on startup whem power was applied to the igniter.
1st pic - Shows current after installing a new Harman 4 port circuit board in a Harman P43
2nd pic - Shows current reading an the old Harman circuit board that would not make the new igniter hot enough to get the pellets warm!

Don, you are a stand up guy that deserves a huge thank you. I tested the fans as you said and they tested good. It was the igniter as you predicted . I will be ordering 1 from you after I finish writing this. This is now the second time you have taken the time to help me, I live in MA, the first time you helped me was a few years ago during a bone chilling cold snap we had here in New England, I was having trouble getting a convection blower for this same stove, you had me come to your house and you made me one from a motor and fan you had on hand fitting it to the housing I had. If you didn’t do that for me it would have been several days before I got the stove working due to the part being out of stock everywhere locally!

I can’t thank you enough, not only do you have the parts to repair these stoves, but you share your wealth of knowledge, expertise, and time to anyone needing advice! So on behalf of myself, my family, and everyone you have helped with your forum and stove parts, THANK YOU!!

I have another question for you Don regarding the US Stove 5660 pellet stove. I was able to replace the lower auger bearing by removing the back panel, the convection blower, the auger motor, and the inlet fresh air pipe, I couldn’t see a way to replace the top bearing.

How to you get access to the 2 retaining bolts holding the top bearing in place? To me it looks like the hopper for the pellets and the cabinet of the stove itself would have to be taken apart, which would be a hell of a job because it’s all riveted together! Do you know of another way?

Thanks

Thank you so much for your thoughtful feedback. I'm glad to help. I hope you have a Happy Holiday.

Hello
Unlike the other US Stove models the auger cover in the 5660 does not have screws to remove the cover to access the top bearing.
You may be able to access the top bearing by removing the 2 top screws and removing the top part of the auger cover.
Otherwise you have to remove the auger and motor and use a treaded rod with a washer and nut to reach up the chute to pull it out like the Whitfield stoves. However the top auger bushing does not get the wear like the bottom bushing does so I just lube it with a stick and it lasts a very long time.