Hi crew, long time lurker, first time poster.

I received a free (faulty) hottop, I suspect the mainboard is faulty, there's no light on it and nothing at all on the unit works, as if completely dead.

I removed the mainboard and noticed one of the resistors (R22) with some scorching stains on the board. Pulling the resistor, it appears to have three brown stripes and a black stripe, but measuring it, it's 33.6Kohm! Certainly not right.

Looking at the hottop photos, this resistor is incorrect, or, burnt so badly I can no longer make out the true colour of the codes on it.

Was wondering if someone who knows about hottop boards could help me out with this one. Anyone know what resistor this should be? Does it differ between 110 and 240V models? I have a 240V model.

Photos attached:

Assuming it's a 1/2W resistor, 33.6K might make sense if there is 117V across it.

Ira

240V.

Ultimately I need a photo of someones 240V board so I can go buy a new resistor (if it's the fault)

The 120v versions have a fuse linking the hot lead from the power cord contact with the rest of the board. The fuse is covered with black heat shrink tubing & isn't obvious. If the 230v version has one be sure to check it first.

John, the link passes the 'beep' test and seems fine....

I'm not talking about the fusible link if that's what you tested. In the lower photo here:
http://www.hottopusa.com/AllWire.jpg You can see the glass fuse covered with heat shrink tubing & 1.5" leads coming out both ends plugged into the board. All power from the power cord attachment at the board passes through this fuse. This may not be on the 240v board but if it is be sure to check it if you haven't already.

John, yes, I tested that part (not talking about the fusible link). it tests fine.

I just received a photo of an AU main board in my inbox, it seems I was right about that resistor, it's looking pretty dead!

I was looking at the link to the photo of the main board (AllWire.jpg). If you zoom in, you can see the resistor in question. It's value looks like three red bands 2.2K 5% tolerance. It is also probably a flame proof resistor. My guess is a 2 Watt but it is hard to tell.



Jack

JackH wrote:I was looking at the link to the photo of the main board (AllWire.jpg). If you zoom in, you can see the resistor in question. It's value looks like three red bands 2.2K 5% tolerance. It is also probably a flame proof resistor. My guess is a 2 Watt but it is hard to tell.

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Jack

Well, the Australian version is "brown, green, yellow, gold". Which I think is 150kohm. Confirmed by a photo of an AUS board from the AUS hottop distributer. I purchased and replaced the resistor and it still doesn't work, at all, complete darkness.

I dunno

Not really wanting to fork out $300 for a new board, even if I did get the roaster for free! hrmmmm.

I would suggest you need to take special care as I have seen plenty of burnt resisters and teh Colours you reference as being from an Australian look nothing like the burnt resister...

Would need to see under a strong magnifying Lamp to say for sure..

In addition there are tricks to measuring these types of resistors after minor burns to get a close idea...

Further more a resistor burns like that with excess current / voltage. Would suggest a FET or High Power transistor has maybe blown as well.

WHY !!! What did the last person DO or try to DO ?

1: Wrong Supply ?

2: Blown element ? New board and it will burn out again

3: Eject coil shorted ? New board and it will burn out again

If you do not find the root cause, tossing one or two parts will only lead to more $$$ wasted. Unless your very lucky. But at $300 for a main board... Not worth the risk..

If you add in the other parts that could cause it to fail, element / solenoid / Fan ? Drum Motor etc and a new Board = GET A NEW MACHINE...