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Thread: 12 vs 12.5 uF

  1. #1
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    Hmm 12 vs 12.5 uF

    Hi. Can I swap 12uF and 12.5uF for a blower? Will doing so cause any issue?

  2. #2
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  4. #3
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    Changing a capacitor from the value determined by the motor manufacturer usually raises the current drawn by the motor, and because of that, increases the heat the motor creates, which can shorten motor life.


    You can use a different value temporarily, until you reach starbase for a new cap, since they can't be replicated.
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  6. #4
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    So, .5 will make a difference?

  7. #5
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    Quote Originally Posted by hvactrekkie View Post
    So, .5 will make a difference?
    Yes.


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  8. #6
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    Not if you use the + or - 5% rule. I've seen 6% and 10% used also.When in doubt,get the exact replacement!

  9. #7
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    I doubt his 12.5 is even 12.5 to begin with. More like 12.3 out of the box. And if it is exactly 12.5. It won't be for long. That's why the cap manufacturer puts the +or- on the box because they can't guarantee it to be on the money. The rule for replacement is + or minus 10%. I think you'll be OK.

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  11. #8
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    What about sizing up a compressor capacitor. Let’s say 5-10 mfds. Increases heat as well?

  12. #9
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    Quote Originally Posted by OGlad View Post
    What about sizing up a compressor capacitor. Let’s say 5-10 mfds. Increases heat as well?
    You can't go 10 mfd. It defies the rule. As 10% of a 80 mfd is 88 not 90.

  13. #10
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    99,9 % sure, you can swap them, no problem.

  14. #11
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    Sorry I forgot, may be you know, The isolation voltage must be equal or bigger in the new cap.

  15. #12
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    If a 12uf capacitor isn't ok to swap for a 12.5 is a 12.5 rated cap reading 12 ok? I agree that you should always use the proper cap and if you do swap a 12 for a 12.5 you should note it for future reference. It is also always a good idea to take a reading of the new cap
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