Stove Fan Speed!

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eric426

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Joined
Aug 29, 2011
Posts
8
Location
Coupeville, Wa.
;D
Hi, I am Eric.  I am New to this forum. But thought I would pass on some fix info. on My stove fan speed. I am sure there some other kinds of fixes out there, but I am nicely satisfied. I have the standard 12 volt noisy high speed fan that come with lots of Rigs. I seen a fix on another site. But I went to find the Resistors At R.S. and could not find them anywhere. I went to an Electronic parts store. They did not have them either. But the Owner suggested a nice Single turn 25 Ohm Rheostat. All he had was a 50 Ohm. So I used that. Really nice and smooth speed. Slows it down quiet and can speed it up high too. At almost slow speed it keeps the outside door still open, no problem. I Just drilled a hole in front of the hood next to the on/off switch and installed it. I can shut it off and turn it on and adjust the speed. I just spliced the wires into the same wires on the Fan hood.  Wired it between the switch and fan.  Rheostat I used as follows..

501-0001
ku5001s28
50 ohm
single-turn
rv4naysd500a
carbon

Hope this is good for yours if needed,  Eric  ;)
 
NICE!  I don't know how many times I thought that very same thing pertaining to the noise that stupid fan makes!
And I never thought of installing a rheostat in place of the switch. 
Great idea and thank you.

I am assuming that the number 501-0001 is the RS part number.  It looks like their numbering system.  Am I correct?
 
You now I am not sure how the Part numbering works. But just take these figures to an Electronic parts store and they can look it up. These are all the number that came off the package it came in.  NTE Electronics packaging, Bloomfield, NJ.
  Also I still use my on/off switch. I just put the Rheostat between the switch and fan.  Believe me it, is nice and smooth....  good luck  eric
 
I believ that you have installed a Potentiometer, a variable resistor working as a variable voltage divider. Can be used as a Rheostat, with only 2 wires connected. A Rheostat is designed to limit current and comes in small to large wattage sizes.

Using a carbon Potentiometer puts you at the risk of overheating and destroying the unit. You might want to see if overheating at slow speeds shows up on your control. Hopefully all works out for you.

Carson FL
 
BINGO!  Thanks Carson.

While I don't think a stove fan has sufficient enough of a current draw to pose a problem, I wanted to know for sure by getting the RS part number and checking the specs.

 
it aint the slow speeds that will blow it up, its the high speeds.

use a good ohmmy meter and find the resistance of the motor.  its easy to find the max current that can flow on a 13.8v circuit.  now you have a good idea of the wattage required.
 
Ahem....quaddriver. Would you rethink your answer?

A couple of points.  At high speed the pot is in the zero ohm position; no power dissipation... no heat.
  At low or medium speed part of the resistor is being used and will be dissipating power....heat.


Measuring with an Ohm meter is useless. DC motors have a commutator and brushes, connected to individual wires on the rotor.hence no value in reading that.

One way to measure actual current draw is to measure with an ammeter.

Another way is to measure the voltage on the resistance in use on low or medium speed. Then use Ohm's Law;;;E=I*R,
To find the current use I=E/R.
  and so on...

Carson
 
Maybe quaddriver misunderstood which would "blow up"?  The rheostat, the factory installed switch, or the fan blower motor?

Carson is spot on.  After the holiday, I am going to dive into this deeper.  I hate that fan!  Just a very small piece of camping that irritates me.

Thanks for the link Carson.
 
Hey guys, you can debate this subject all you want. You raised some good concerns. The Electronics guy did say I would be trading resistance for heat.  But I know this is sweet and quiet. I did check for heating up and it seemed normal.  Also the Poten. is in the metal housing.  Plus the fan is not going to be on long for just cooking anyway.  This was a simple installation and is quiet when adjusted down. 
I will be the first to let you now if my trailer burns to the ground because of my new fan speed!!!!
Joke:: My wife is such a bad cook! We left the dental floss on the counter in the kitchen and the cockroaches all hung themselves..

good luck, & thoughts...    eric
 
The only issue you may encounter is that on slow speeds, considerably slower than factory, the metal flapper that blocks the fan venting hole may not open rendering your vent less than efficient.
 
Tested our fan this last week camping. WORKS GREAT!  Did a touch test for heat. Not much heat build up. Warm to the touch. The door was open enough to allow flow.  Ran it about half speed and not noisy.

eric  :) :)
 

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Thanks Eric, I am going to follow your example and install one on our fan. The DW will love me for installing it ...and you for suggesting it    ;)

Welcome to the forum
Howard
 
    Not being into the finer points raised in this string, I ask, is there any reason why you couldn't go to a junk yard and get a fan switch that is designed to handle variable speeds.  It wouldn't be infinite range, but the 4 or 5 speed settings should suffice.

Ed
 
Hfx_Cdn said:
    Not being into the finer points raised in this string, I ask, is there any reason why you couldn't go to a junk yard and get a fan switch that is designed to handle variable speeds.  It wouldn't be infinite range, but the 4 or 5 speed settings should suffice.

Ed

Some of us are just a little cautious of buying someone else's problems from a junk yard.  It's sounds like you might be pertaining to a fan blower switch for an automotive application.  While it may work, the specs for a new rheostat are available (and not expensive) and the part being fresh out of the box is comforting.
 
Using an automotive fan switch by its self may not work, most (all) I have around here switch between resistance windings installed in the fan discharge. Disclaimer; there may be some with the switch and resistors in one unit but I haven't seen one.
 
My Potentiometer has a nice smooth turn from Zero to fast.  I have my set around half and the speed is enough to keep the outer door open and is quiet.    It is simple and I do not have to look around a dirt junk yard.  My Electronics guy did not have the 25 ohm so we tried the 50 Ohm.  I love it.

eric :) :) 8) 8)
 

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