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Will Freeze Spray Temporarily Lower The ESR Value?

By on January 7, 2010

Assuming if you do not have ESR meter, how do you spot a bad electrolytic capacitor in electronic circuit? You knew that, using digital capacitance meter to check electrolytic capacitor will not give an accurate answer because, for a bad capacitor, the meter would show that the bad cap is good even though the ESR value already shot up many times. What if you have a can of FREEZE spray (Coolant) in your workshop. Will the Freeze spray detect bad capacitors (high ESR value) in electronic circuit?

The answer is no- because i had tested many bad filter capacitors that have high ESR value, the ESR meter reading don’t show any changes (turn to lower ESR value) at all. It other words, the bad caps ESR value does not show any respond when the Coolant was used to spray on the bad capacitors. However, if the capacitor have intermittent problem (due to heat and cold), Coolant is the best to find out the intermittent fault.

If you do not have any ESR meter, please get one because you do not know what you are missing as an electronic repairer. I personnally have not heard of anyone in this repair trade that they regret using ESR meter.



  1. jgmanza

    January 7, 2010 at 12:45 pm

    Hello Jestine,
    Happy New Year.

    I got my esr meter in November, and I have yet to find a electrolitic with high esr. What I found was 200v 220uf electrolytic with low esr of 0.4. When i double checked with my analog meter it was shorted. Taking the cap out of circuit showed the same results. A replacement restored the tv to work properly.

    Best Regards

  2. admin

    January 8, 2010 at 9:22 am

    Hi Jorge,

    Thanks for sharing!


  3. John Preher

    January 8, 2010 at 5:53 pm

    Jorge, remember the ESR values on the meter are only average values. Sometimes an ESR may be High for the circuit the capacitor is in even though it seems pretty low. You need to also compare with good capacitors not just your chart. I had a projection TV the other day with bad DM module symptoms(continually flashing timer light, green light of death), I removed the DM module and checked the ESR of the 7 1000uF 16V capacitors in the DM module power supply(these often cause DM failure), all had an ESR of around 0.5-0.7 ohms, which seems pretty low but it is too high for this circuit, it should be around 0.04-0.07 ohms for each of the capacitors. Relacing the 1000uF 16V capacitors caused the TV to start working perfectly again.

  4. John Preher

    January 9, 2010 at 4:00 am

    just to clear any confusion I meant to say the values listed on the front of the meter are averages values.


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