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I 've been having problemswith the A/C system in my car. I had the fuse box replaced with a Bob Timma fuse box and since then my A/C fuse continues to fail after using my A/C after 5-10 minutes, every time ! The fuse blows, then the condenser fan stops and the new rotary compressor expunges all of my R-134 refrigerant. Can someone help me, I'm tired of replacing the fuse and the refrigerant.
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Both power circuits for the condenser fan and the compressor clutch should originate from fuse #7. They are red and yellow-black wires. If the fuse blows, then the whole enchilada shuts down.

It sounds like your replacement fuse panel separated those circuits. There might be extra terminals at fuse #7 and you could simply relocate the wires.

The next question is WHY you are blowing fuses. It might be that fan is failing and causing a high load. The fuse should be a 30 amp rating. Check that too.
Where is your refrigerant expunged from?
If it is a pressure release, most are set for 550 psi and that is way to high a pressure. The more 'modern' / safer way is to use a high pressure switch which shuts off the compressor.
Have you connected up a/c gauges to read what is happening?
Is your condenser fan working or working correctly? This is a common reason for high pressures.
What else does your fuse that blows also control?
70 stang,

As others have said, the likely chain of events are:

1> Condenser fan stops working because of the fuse blowing. The fuse blows because, a. the fuse is the incorrect size, b. the Fan is going bad and eventually blows the fuse, c. something else on the same circuit is drawing to much power.

2> Once the condenser fan blows the pressure in the system continues to rise until it causes the pressure relief valve to open. (This is expected behavior if the compressor continues to run without the condenser fan running and no over pressure switch in the system)

If the system was designed properly, you would have a trinary switch at the drier to turn off the compressor once the safe pressure is exceeded. Since the system is empty, now is the time to add the trinary switch. That way, next time the fuse blows, you will not loose any refrigerant.

Take care, Scott
Try disconnecting the condenser fan wire at the fan. Turn the key on and turn on the A/C switch (engine off). Wait and see if the fuse blows.

If the fuse blows, then there is an issue with the wiring to the condenser fan. If the relays are mounted above the passenger foot well, look to see if the cover that covers all of the relays has pinched a wire.

If the fuse doesn't blow, then reconnect the condenser fan wire and try again. If the fuse blows, then the condenser fan is bad. If the fuse still doesn't blow, then turn on the blower motor and try again.

You could have the blower motor or a radiator cooling fan (or both) connected to the A/C fuse.

By doing these tests with the engine off, you won't be losing refrigerant.

You may want to connect a battery charger to the battery for these tests.

As has been suggested above, you should add at least a binary switch to the refrigerant system. This will turn off the compressor clutch if the pressure gets too high, or if the pressure is too low.

John
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