NuTone IM3003 Water Damage - Part 2
Thursday, September 19, 2013 at 9:07AM Sometimes water-damaged Intercoms will require extra effort to repair the damage caused by the circuit board corrosion. This NuTone IM3003 was originally damaged 2-3 years ago and nothing was done about the problem.
The corrosion was so bad that it had eaten away the metal leads on many of the components.
The red arrows point to the leads of 2 diodes that were completely eaten away and were no longer connected to the circuit board.
The corrosion has also eaten away the leads from several capacitors on the board.
Here are the capacitors after they were removed from the board. The leads are almost completely eaten away by the corrosion.
The only correct method to rebuild such a severally damaged board is to remove all of the components and clean the board.
Inside the red boxes you can see that all new diodes have been installed in place of the damaged parts.
The red arrows point to the new resistors that have been installed. The blue arrow points to 4 ceramic capacitors that were also replaced.
New electrolytic capacitors are installed on the board. These would have been replaced as part of the normal rebuild process of a IM3003 power supply board.
Finally, the amplifier IC and voltage regulator (mounted on the heat sink) are reinstalled. The amplifier IC had to be replaced because its leads were eaten away just like the other components. This is unfortunate because the amplifier IC is an expensive part.
After this initial repair work was completed, the IM3003 was reassembled and tested. I found a few other problems with the Intercom Control section on this board. These were not direct corrosion problems, but they may have been caused by some of the other failures on the board.
After all of the problems were solved, the entire IM3003 was rebuilt and it is now back in service.
If your IM3003 is in need of Repair, use this link to contact us
Use this link link to our Intercom Reapir Request Form.