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MTH Steam engine, smoke heater comes on, analog or DCS, fan does not. Disassembled engine, power applied to fan connector pigtail and fan works fine. Traced fan wires individually from fan all the way to connector that plugs into cable which then plugs into the tender. I then, while still all hooked up continued to trace each wire through the engine to tender cable then from tender connection all the way to where the wires plug into the PS3 stacker board. All other functions of engine work well under DCS and analog. Engine has been hard reset and soft reset, no change.
Heating element switches on via DCS and smoke will come out from bottom area of boiler as smoke fan never comes on.
Any ideas? Or is this just a bad board function ?
Average person of course has no access o boards or schematics of these engines.
 

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Is the impeller on the fan either not seated far enough down or down too far? I've had it happen several times where the impeller was pushed down too far and bound up on the housing. I've also had it happen where the impeller became too loose on a motor shaft and didn't spin with the smoke fan motor.
 

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Is the impeller on the fan either not seated far enough down or down too far? I've had it happen several times where the impeller was pushed down too far and bound up on the housing. I've also had it happen where the impeller became too loose on a motor shaft and didn't spin with the smoke fan motor.
Maxum, thanks for the suggestions, I actually took fan connections, plugged in a matching connector and applied voltage to the fan and it spun freely and normally I think.
 

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Maxum, thanks for the suggestions, I actually took fan connections, plugged in a matching connector and applied voltage to the fan and it spun freely and normally I think.
If the impeller is not seated far enough down, the fan will lock up when you put the board over the impeller and it binds up.
 

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Are you getting voltage on the Fan's controller board socket. Since you ran the fan from it's pigtail, check the voltage at the connector.
 

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Are you getting voltage on the Fan's controller board socket. Since you ran the fan from it's pigtail, check the voltage at the connector.
Mike, I only tested continuity from fan to board connector in tender without power on train. I am assuming with continuity all the way on both wires to connections on board that no voltage is being produced by board. But you are correct that would be next thing to confirm! Have train on, smoke on Tender apart and carefully get on the tiny connections on the stacker board assembly. Thats a little hairy to do, this is why I thought I would ask the group and maybe someone has seen this issue. Hoping its not a "board" problem" but thinking it might be.
Thanks Nick
 

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What is the specific MTH model number?

The fan motor may be drawing too much current, that can happen as well. If you've checked end to end continuity of both smoke fan motor wires, then you're probably down to the motor or the board. A good smoke motor should spin when connected to a 1.5V battery. If you have a current capable meter, the motor should draw around 30-40 milliamps with 5VDC applied. If it draws more than about 50 milliamps, it needs to be replaced.
 

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Average person of course has no access to boards or schematics of these engines.
Joe Average here. PS3 schematics have been published but if you have traced the fan wires to the board, which it sounds like you have, you know where to test.

Access to PS2/3 boards is something else - that I don’t pretend to understand.

But, like the man says, it would help to know the MTH model number.
 

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Joe Average here. PS3 schematics have been published but if you have traced the fan wires to the board, which it sounds like you have, you know where to test.

Access to PS2/3 boards is something else - that I don’t pretend to understand.

But, like the man says, it would help to know the MTH model number.
Sorry I will get the model number and put it here , didnt measure current draw as suggested yet either. Sorry been distracted by work travel lately.
Nick
 
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