AC just stopped working….looking for advice……

ken burke wrote:
Can you be more specific as to how to check each side?

You need a multimeter. You can get one at lowes, home depot, or walmart.

Here are two ways to check.

1. Find two wall outlets that are on different sides of the 240 supply line. You can do this as follows. Look at a 120 wall outlet so that the round ground connection is on the bottom. You will see two slotted holes - one is longer than the other. The long one is neutral and the short one is hot. Place one meter lead in the short slot of this outlet. Now find another wall outlet and place the remaining meter lead in the short slot on that one (you might need to use an extension cord to reach the second outlet - just measure from the short slot on the extension cord). If you read 0 volts, you are on the same side of line so find another outlet and repeat the action. When you find an outlet where you measure around 240 volts with respect to the first outlet, you have found one on the other side of the supply line. Now that you have identified two outlets on different sides of the 240 supply, you simply measure across the first outlet (shot slot to long slot on that outlet) while starting the AC. The voltage should should remain above 105 during the start and above 110 at all other times. Repeat the test on the other wall outlet you identified. If either outlet shows lower than expected voltage, suspect a problem with the shore power system and it's associated cables.

2. Remove the panel cover to the distribution panel and measure between where the red wire connects and neutral. You should see the same voltages discussed above while starting the AC. Now measure between the black wire and neutral. Again, you are looking for the voltages as described above while starting the AC.

It is important to measure the voltages under AC start conditions. Measuring these voltages without a similar load can result in a false reading that might indicate a good connection when that is not the case. If these voltages appear OK, you probably have a problem in the AC (or the cable that connects it to the distribution panel. I am sure you already know this but please remember that the voltages (actually currents) you are working with can kill you DEAD DEAD DEAD. In most cases things are perfectly safe but just be careful. If you don't feel comfortable doing this I suggest you don't.

Mike