Protecting absorption refrigerators PCB
The last few years during the storm season I've been having issues with my refrigerator (Norcold N641) not working temporarily. At first I thought there was something wrong with the PCB as the frig...
Forum Discussion
After removing the PCB I'm finding green mold on some of the chip legs and a some near the 16-pin plugin.
I'm not certain the best approach of removing the green mold which seems to be stuck to some of the chip legs solder into the pcb.
I think what may have happened is the pcb became laden with moisture so many times a year over many years (10+) where green mold/mildew developed.
The RV is kept most of the time in a climate with an average annual precipitation of approx 70 inches. The climate much of the year has around 80 percent humidity.
I thought I had cleaned off any green mold and mildew however I guess not good enough as it seems just enough has stayed on the electrical contact posts which reacts to any moisture surrounding the pcb. The PCB cover isn't air tight so any moisture in the air may effect the pcb with even small amounts of green mold/mildew which is essentially a very fine corrosion.
Overtime the mildew keeps building up even if there's no water that comes in direct contact with the pcb. During a heavy rain storm the humidity increases to 90+ percent and the pcb with even small amounts of fine mildew chemically reacts to excessive humidity.
I've removed the PCB but it may be difficult to completely remove the green mold/mildew (corrosion) that become attached to some of the chips legs soldered into the PCB. I've tried using some electronic contact spray and a toothbrush. However I'm not certain how well that working.
I probably need to soak the pcb in a solution that will neutralize the mold and fine corrosion without effecting the pcb and it's electronics.
Perhaps a naval jelly? Which essentially is phosphoric acid that turns the mold & corrosion into iron phosphate which then can be flushed away with some electronics spray?
So essentially I think the pcb even though protected somewhat from direct contact with water is reacting to higher humidity over many years enough that small amounts of corrosion (green mold) develops.
Once I'm able to totally clean the pcb and apply a coat of Conformal Coating should help prevent the corrosion (green mold) from developing in the future.
I'm not certain the best approach of removing the green mold which seems to be stuck to some of the chip legs solder into the pcb.
I think what may have happened is the pcb became laden with moisture so many times a year over many years (10+) where green mold/mildew developed.
The RV is kept most of the time in a climate with an average annual precipitation of approx 70 inches. The climate much of the year has around 80 percent humidity.
I thought I had cleaned off any green mold and mildew however I guess not good enough as it seems just enough has stayed on the electrical contact posts which reacts to any moisture surrounding the pcb. The PCB cover isn't air tight so any moisture in the air may effect the pcb with even small amounts of green mold/mildew which is essentially a very fine corrosion.
Overtime the mildew keeps building up even if there's no water that comes in direct contact with the pcb. During a heavy rain storm the humidity increases to 90+ percent and the pcb with even small amounts of fine mildew chemically reacts to excessive humidity.
I've removed the PCB but it may be difficult to completely remove the green mold/mildew (corrosion) that become attached to some of the chips legs soldered into the PCB. I've tried using some electronic contact spray and a toothbrush. However I'm not certain how well that working.
I probably need to soak the pcb in a solution that will neutralize the mold and fine corrosion without effecting the pcb and it's electronics.
Perhaps a naval jelly? Which essentially is phosphoric acid that turns the mold & corrosion into iron phosphate which then can be flushed away with some electronics spray?
So essentially I think the pcb even though protected somewhat from direct contact with water is reacting to higher humidity over many years enough that small amounts of corrosion (green mold) develops.
Once I'm able to totally clean the pcb and apply a coat of Conformal Coating should help prevent the corrosion (green mold) from developing in the future.
