[Sylvain Gregoire]

Our Maytag EQ Plus dishwasher stopped working yesterday.

The problem is on the control board, the VR300 thermistor
(located near one corner of the board) is melted/opened.
This component supplies power to part of the circuit.

A picture of this model of control board can be found he
http://www.repairclinic.com/0081.asp...&SeqID=1&Chg=1

Anyone knows the thermistor part number I could order/use to replace it?
I am trying to avoid purchasing an expensive complete control board.

Incidentally, I have been fixing electronics professionally for many years,
I do not need to be warned about safety, etc.

Thank you,
- Sylvain in Ottawa, Canada

[Sylvain Gregoire]

Correcting typo in post title.
I should drink my morning coffee before posting!

Cheers,
- Sylvain

"Sylvain Gregoire" wrote in message
...
Our Maytag EQ Plus dishwasher stopped working yesterday.

The problem is on the control board, the VR300 thermistor
(located near one corner of the board) is melted/opened.
This component supplies power to part of the circuit.

A picture of this model of control board can be found he
http://www.repairclinic.com/0081.asp...&SeqID=1&Chg=1

Anyone knows the thermistor part number I could order/use to replace it?
I am trying to avoid purchasing an expensive complete control board.

Incidentally, I have been fixing electronics professionally for many
years,
I do not need to be warned about safety, etc.

Thank you,
- Sylvain in Ottawa, Canada

[Homer J Simpson]

"Sylvain Gregoire" wrote in message
...

Anyone knows the thermistor part number I could order/use to replace it?
I am trying to avoid purchasing an expensive complete control board.

Why not try a resistor?

[Ken Weitzel]

Homer J Simpson wrote:
"Sylvain Gregoire" wrote in message
...

Anyone knows the thermistor part number I could order/use to replace it?
I am trying to avoid purchasing an expensive complete control board.

Why not try a resistor?

Arghhh, hope you're kidding Homer

Take care.

Ken

[Homer J Simpson]

"Ken Weitzel" wrote in message
news:lQDOg.557779$IK3.156483@pd7tw1no...

Why not try a resistor?

Arghhh, hope you're kidding Homer

Not at all. Ask yourself what the thermistor does.

[Ken Weitzel]

Homer J Simpson wrote:
"Ken Weitzel" wrote in message
news:lQDOg.557779$IK3.156483@pd7tw1no...

Why not try a resistor?
Arghhh, hope you're kidding Homer

Not at all. Ask yourself what the thermistor does.


Hi Homer.

Ok, guess I'm old enough to be excused for talking
to myself

Old enough that my memory isn't as sharp as it used
to be. And my memory isn't as sharp as it used to be.

So, a thermistor when cold (ambient) is virtually a
low value resistor. But as it conducts it very quickly
heats up, and in doing so becomes a very high value resistor.

The failure of a plain old resistor not increasing dramatically
in value could annoy what's on the other side of it.

Am I still right? (my memory isn't as sharp as it used to be

Take care.

Ken

[Michael A. Terrell]

Homer J Simpson wrote:

"Ken Weitzel" wrote in message
news:lQDOg.557779$IK3.156483@pd7tw1no...

Why not try a resistor?

Arghhh, hope you're kidding Homer

Not at all. Ask yourself what the thermistor does.


I know what it does. It is a resistor that changes value, relative
to the ambient heat. No manufacturer would use a thermistor where a
much cheaper resistor would work.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

[Homer J Simpson]

"Michael A. Terrell" wrote in message
...

Not at all. Ask yourself what the thermistor does.

I know what it does. It is a resistor that changes value, relative
to the ambient heat. No manufacturer would use a thermistor where a
much cheaper resistor would work.

Yes, but why? Is it for a slow start? Ambient compensation? Feedback
compensation?

As a test, use a resistor. Figure out the value needed. That'll be a guide
to the thermistor to use. At this point, is it a PTC or NTC?

[Michael A. Terrell]

Homer J Simpson wrote:

"Michael A. Terrell" wrote in message
...

Not at all. Ask yourself what the thermistor does.

I know what it does. It is a resistor that changes value, relative
to the ambient heat. No manufacturer would use a thermistor where a
much cheaper resistor would work.

Yes, but why? Is it for a slow start? Ambient compensation? Feedback
compensation?

As a test, use a resistor. Figure out the value needed. That'll be a guide
to the thermistor to use. At this point, is it a PTC or NTC?


Go ahead and try the resistor. Don't be surprised if you do a lot
more damage to the machine. Personally, I would try to get my hands on
a couple junk boards from a repairman or another source, and hope that
its not the only part that fails. You have no idea what it does, or
what damage you can cause. I watched a tech spend three weeks trying a
resistor in a clothes dryer that was supposed to sense how dry the
clothes were, before he gave up and bought a board. If I needed one, I
would offer the local recycling place a few bucks to keep an eye out for
the same type of dishwasher, and have them call me when it showed up,
for another $10 bucks to the guy that found it. they strip the circuit
boards out of appliances when they separate the metals, and sell them by
the pound to places that legally burn the boards to recover the silver,
gold, copper and solder. If I wasn't 100% disabled, I'd visit them a
couple times a week and offer a little more per pound for boards in good
shape. I sometimes find usable parts on old appliances at the local
transfer station where I dump the used steel from computers, rather than
drive 25 miles to the main recycling center. Things like 24 VAC
transformers on old furnaces and central air units, small contactors and
thermal safety switches.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

[Homer J Simpson]

"Michael A. Terrell" wrote in message
...

Go ahead and try the resistor. Don't be surprised if you do a lot
more damage to the machine.

All good suggestions. But sometimes you just have to cut and try.

[Michael A. Terrell]

Homer J Simpson wrote:

"Michael A. Terrell" wrote in message
...

Go ahead and try the resistor. Don't be surprised if you do a lot
more damage to the machine.

All good suggestions. But sometimes you just have to cut and try.


Not on my toys. ;-)


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

[Homer J Simpson]

"Michael A. Terrell" wrote in message
...
Homer J Simpson wrote:
All good suggestions. But sometimes you just have to cut and try.

Not on my toys. ;-)

Perhaps you missed this from the OP: -

"Incidentally, I have been fixing electronics professionally for many years,
I do not need to be warned about safety, etc."

I took that as a statement of expertise.

[sg]

Thanks to all for the input.
Turns-out that this device is actually a surge protector !

I was able to find the wiring diagram of the dishwasher,
and while there is no diagram for the control board itself,
I was able to figure-out that the device is basically connected
across the 120VAC power line mains once the door switches
are closed.

Thus, the melted VR300 'thermistor' is actually a surge protector.
Thankfully I had not tried the thermistor replacement trick yet.

I did further tests on that board, and discovered that a few diodes
including at least one zener are either short or opened...
Plus a 2N3904 transistor is short too.
I guess the surge protector did not quite protect the rest of the
circuit.
I wonder if this occured during a storm (I was not at home when the
dishwasher became defective).

Given that there are too many bad parts on the board, plus there
may be more chips zapped too, and given my limited spare time
(and my wife threatening to call a serviceman!),
I will have to bite the bullet and buy the replacement board
Darn, I thought it was going to be a simple single bad part...

Thanks again for all the input and interesting discussions,

Regards,
- Sylvain

[Homer J Simpson]

"sg" wrote in message
oups.com...

Thanks to all for the input.
Turns-out that this device is actually a surge protector !

Given that there are too many bad parts on the board, plus there
may be more chips zapped too, and given my limited spare time
(and my wife threatening to call a serviceman!),
I will have to bite the bullet and buy the replacement board
Darn, I thought it was going to be a simple single bad part...

Can you get a rebuilt to save some bucks?

[David Naylor]

Sylvain Gregoire wrote:
Our Maytag EQ Plus dishwasher stopped working yesterday.

The problem is on the control board, the VR300 thermistor
(located near one corner of the board) is melted/opened.
This component supplies power to part of the circuit.

A picture of this model of control board can be found he
http://www.repairclinic.com/0081.asp...&SeqID=1&Chg=1

Anyone knows the thermistor part number I could order/use to replace it?
I am trying to avoid purchasing an expensive complete control board.

Incidentally, I have been fixing electronics professionally for many years,
I do not need to be warned about safety, etc.

Thank you,
- Sylvain in Ottawa, Canada


Go to Repairclinic.com you will get all you want to know and by rhe
part from them GREAT SITE

[Michael A. Terrell]

Homer J Simpson wrote:

"Michael A. Terrell" wrote in message
...
Homer J Simpson wrote:
All good suggestions. But sometimes you just have to cut and try.

Not on my toys. ;-)

Perhaps you missed this from the OP: -

"Incidentally, I have been fixing electronics professionally for many years,
I do not need to be warned about safety, etc."

I took that as a statement of expertise.


I take what I see in front of me as evidence. I have had hundreds of
people assure me that they were VERY good electronics techs, yet they
couldn't do anything right. Call me cynical, but after you've seen some
really stupid stunts, you want to be damn sure of what is going on.


In this case, the bad part was across the AC line. What good would
your random choice of a fixed resistor have done, other than cause more
damage, or even start a fire?

--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

[Homer J Simpson]

"Michael A. Terrell" wrote in message
...

I take what I see in front of me as evidence. I have had hundreds of
people assure me that they were VERY good electronics techs, yet they
couldn't do anything right. Call me cynical, but after you've seen some
really stupid stunts, you want to be damn sure of what is going on.


In this case, the bad part was across the AC line. What good would
your random choice of a fixed resistor have done, other than cause more
damage, or even start a fire?

A 1 meg resistor?

[Michael A. Terrell]

Homer J Simpson wrote:

"Michael A. Terrell" wrote in message
...

I take what I see in front of me as evidence. I have had hundreds of
people assure me that they were VERY good electronics techs, yet they
couldn't do anything right. Call me cynical, but after you've seen some
really stupid stunts, you want to be damn sure of what is going on.


In this case, the bad part was across the AC line. What good would
your random choice of a fixed resistor have done, other than cause more
damage, or even start a fire?

A 1 meg resistor?


How many 1 meg thermistors have you seen?


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

[Homer J Simpson]

"Michael A. Terrell" wrote in message
...

A 1 meg resistor?

How many 1 meg thermistors have you seen?

It wasn't a thermistor.

[Michael A. Terrell]

Homer J Simpson wrote:

"Michael A. Terrell" wrote in message
...

A 1 meg resistor?

How many 1 meg thermistors have you seen?

It wasn't a thermistor.


You thought it was when you told him to replace it with a fixed
resistor.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

[Homer J Simpson]

"Michael A. Terrell" wrote in message
...

You thought it was when you told him to replace it with a fixed
resistor.

Perhaps you missed this from the OP: -

"Incidentally, I have been fixing electronics professionally for many years,
I do not need to be warned about safety, etc."

I took that as a statement of expertise.

[Michael A. Terrell]

Homer J Simpson wrote:

"Michael A. Terrell" wrote in message
...

You thought it was when you told him to replace it with a fixed
resistor.

Perhaps you missed this from the OP: -

"Incidentally, I have been fixing electronics professionally for many years,
I do not need to be warned about safety, etc."

I took that as a statement of expertise.


Changing the subject to hide your mistake? Shame on you. Perhaps
you think I'm stupid, but I'm not.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

[Homer J Simpson]

"Michael A. Terrell" wrote in message
...

Changing the subject to hide your mistake? Shame on you. Perhaps
you think I'm stupid, but I'm not.

I've yet to see proof of that.

[Michael A. Terrell]

Homer J Simpson wrote:

"Michael A. Terrell" wrote in message
...

Changing the subject to hide your mistake? Shame on you. Perhaps
you think I'm stupid, but I'm not.

I've yet to see proof of that.


That's because you're trolling, as usual.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

[Homer J Simpson]

"Michael A. Terrell" wrote in message
...

That's because you're trolling, as usual.

Speak for yourself.

[Michael A. Terrell]

Homer J Simpson wrote:

"Michael A. Terrell" wrote in message
...

That's because you're trolling, as usual.

Speak for yourself.


If you're not a troll, what are you posting in that anti-Semitic
thread from a homosexual group? Why are you constantly lying about
things you've said?


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

[Homer J Simpson]

"Michael A. Terrell" wrote in message
...

If you're not a troll, what are you posting in that anti-Semitic
thread from a homosexual group? Why are you constantly lying about
things you've said?

All you ever do is troll.

[Michael A. Terrell]

Homer J Simpson wrote:

"Michael A. Terrell" wrote in message
...

If you're not a troll, what are you posting in that anti-Semitic
thread from a homosexual group? Why are you constantly lying about
things you've said?

All you ever do is troll.


If you say so! After all, who's going to argue with a cartoon
character?


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

[Homer J Simpson]

"Michael A. Terrell" wrote in message
...

If you say so! After all, who's going to argue with a cartoon
character?

So that's why they won't argue with you?

[Michael A. Terrell]

Homer J Simpson wrote:

"Michael A. Terrell" wrote in message
...

If you say so! After all, who's going to argue with a cartoon
character?

So that's why they won't argue with you?


I should have plonked you a long time ago. You're already in the
news:sci.electronics.design bit bucket, now all the other groups that I
see you pollute will be added.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

[Homer J Simpson]

"Michael A. Terrell" wrote in message
...

I should have plonked you a long time ago. You're already in the
news:sci.electronics.design bit bucket, now all the other groups that I
see you pollute will be added.

Won't help you. At best you will become a plonkee.
















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