Have you every had a circuit board repaired

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rick31797

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Feb 16, 2010
133
Canada
I have this Thelin stove and thinking about getting the Circuit board repaired as the new boards are too much money, like the better part of 600.00..
When Jay was there, he knew how to look after his customers as the new company really don't care, they wont sell direct, no matter what the circumstances are..I know the mark up on the parts from my dealer are 136. percent...

By looking at the feedback on the internet from customers after the new company took over it looks they have there work ahead them..

They fail to realize there customers are the company.I have already deter a buyer from buying one of these stoves,just by telling him what i have been through..
I figure most people just replace the boards, just wondering if anybody thought about having them repaired..
 
that's a tough one. i have thought about it if ever mine crapped out, but fixing them is not like fixing the TV board. something goes wrong here and the consequences are bigger.

having said that, if it is an obvious simple fix like a capacitor that you can spot right away, then yes.

anything more complicated, i would just get a new one and sleep better.

there are plenty of electronics boards out there that will help you. but it requires patience, tools and some level of experience/knowledge.
 
Yeah I have repaired one or two...........(I joke, I do electronics repair and engineering for a living !). I have never worked on pellet stove SPECIFIC PCA but electronics are electronics..... Your pellet stove would seemingly be a far easier repair than a TV.
what exactly is wrong with it ?
what model is it ?
how old is it ?
 
its a thelin parlour 3000 , it is 12 yrs old.. this stove runs naturally on 12 volt..it has a transformer in it that changes the volts from 120 to 12 volt.it is also manual start.Turning the stove to fan, to start it, the motor runs very slow, not fast enough to cause enough air to lit the stove., no the motor , i have a new one , and the one that is in it has less then 10 bags of pellets through it.Only two sensors in this stove both replaced. Control switch also replaced..

there is a flashing green LED on the control board, i was told this means there is power going to the board.. when i turn the switch to low med and high, i hear the auger turning, but fan is still going slow.. on the clean setting fan goes fast, i would say normal..
I have check all fuses...the only thing that is left is the board..the board is small 7 inches by 4 inches










 
If you have a good 12V battery connected, does the stove work properly? If it does not, it is probably the power transistor on the board that provides the 12V power to the combustion fan motor. From the board pic, my guess is that the two fan-drive power transistors (one for the feed motor, one for the fan motor) are the two three leaded devices just above the connector, labeled "Q1" and "Q3" (maybe Q5 ?). These devices have a black plastic body with a metal tab sticking out, with a hole in the tab.

When the stove operates normally, do the fans operate at different speeds, depending on the stove operating mode?

Also, is the room fan rotated by the same motor as the combustion fan?
 
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The stove does not work any different hooked directly to 12 volt, or 120 volt.


Normally the fan increases speeds as you change from low , med and high... but now it is turning so slow on all settings except clean, you cannot hear it running.

One thing that is confusing me... the clean setting is to be used when the stove is OFF...when i turn this to clean.. the fan turns very fast.. i would say normal, so at this setting the fan is getting the proper voltage.. Unless this is bypassing the problem

The combustion fan and room fan are the same, , also the input fresh air is also the same.. this stove has two motors, the other is the auger.

I see the transistors you are talking about...they are Q-1 and Q-5

If i could find one of these transistors i would not be afraid to solder a new one in..
the numbers on one is.... both the same numbers

IRFZ34N

I RO45T

7A 9C


did you notice on the circuit board print out, were you can check the voltage of the fan... i am not sure how to do this don't want to cause more damage, i am thinking you would check the voltage at each setting, fan, low med high, and if the voltage is low.. then its what your saying the power transistors.
 
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Im at work when I get home I'll try to make sense of the above, gotta love the "user manual" schematics......
I see a microchip PIC on that board probably 16 bit, its possible that the PIC controls fan speed through PWM....... If so the part itself is easy to find and is in a socket BUT the hex file to program it will not be easy to find, virtually impossible.
the other thought I have is same as above, analog logic controlled via F.E.Ts. transistors

(sorry in my world (our products) we use F.E.Ts)
 
IRF234N is an N channel (power) MOSFET ,
you can test them with a multi-meter......
again I'm at work somebody will chime in on how to test a transistor, or else google search "testing N channel MOSFET"


Is there a schematic for the board, rather than the components within the stove ?
 
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Someone has the newer push button board for your stove on EBay right now for 29.99 starting bid. I'm not sure if that is a plug and play replacement or not. For that kind of money it's worth looking into.
 
Also , check the sensor in the exhaust path and make sure it's not clogged. I think it's the T 2. Ceramic with a round hole in it.
 
I have no schematic for the board,i just have what i posted..i wonder if a dealer would have one..but they probably just replace the boards.

The control board on ebay is not the right one , its for a different stove...

i have checked to exhausted hole on the sensor to make sure its clear, from what i understand the stove would start up and then shut down if the hole was plugged or i had a bad sensor...
 
the new boards don't fit in my old pellet stove , so what they do is fit a new board with an adapter.. board is 349.00 adapter is 170.00 must be quite an adapter, and then living in Canada i get to pay 13 percent taxes..

i have read Thelin parts are over-priced, combustion motor is 330.00 the thing is smaller then a coke can..lol
 
I have never dealt with the guy. But Thiers a guy on eBay that fixes all kinds from different manufactures. May bee worth shooting him a message. See if he will at least take a look at it.
 
There was a member on here darryl123 doing board repairs,may wanna send him a message
 
My used stove had a bad board when I got it, I gave the board to my wife and she fixed it. She teaches electronics at a community college.

Dave
 
sounds like there are a few options out there.. i don't know much about it at all, but checking every part on this small board and there values would be time consuming if that how they do it...
 
Cap cod pondscapes has one and it wont fit my stove , this could be the new board there selling but i would need the adapter to use it,add 170.00 thelin says The Circuit Board i need is Part # 00-0035-0204 Parlour Non-EI Ignition.
 
There is a saying
" When you hear hooves, think horses not zebras."
It is unlikely that the microcontroller is bad. It is much more likely something at the power end like one of the control transistors (MOSFET's).
The bad news is that MOSFET's are very sensitive to static electricity and simply handling them can cause permanent damage. Even pulling the board out to look at it can result in damage.
Unless you are familiar with electronics and know how to handle the components safely, you should not undertake the repair yourself.
If you have to handle the board, to ship it to a repair facility, always touch the chassis before you touch the board. That will discharge any static charge that you have acquired. The board should be wrapped in aluminum foil if you don't have an anti-static bag to put it in.
If you feel comfortable working with static sensitive components, you can get replacement parts at either Digikey or Mouser
Good luck.
 
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what do you think about the 3 pin device that is bolted to the extruded aluminum heat sink.would this be a variable voltage regulator. OR power transistor and possible have something to do with speed control..<

what is wrote on this is HARD to see but there must be a value, maybe its on the other side

ST

WOP004

MOROCCO
TIP 42C


just thinking it something that must get hot and could fail, the heatsink has some bluing on it from the heat dissipating
 
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what do you think about the 3 pin device that is bolted to the extruded aluminum heat sink.would this be a variable voltage regulator. OR power transistor and possible have something to do with speed control..<

what is wrote on this is

ST

WOP004

MOROCCO
TIP 42C


just thinking it something that must get hot and could fail, the heatsink has some bluing on it from the heat dissipating
Tip42 is a bipolar transistor. May be part of the power supply regulation for the logic circuits.
Motor control for dc motors is probably done by pulse width modulation in order to keep the power losses on the circuit board to a minimum. That would more likely be done with MOSFET's and they wouldn't need much of a heat sink.
 
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