On one hand I don't even want to respond to this thread, but really I have to. Where all all of the enviorment friendly posters? Is it OK for an individual to waste refrigerant, and dump it to the atmosphere year after year? People who are not completely trained and equipped to do AC (refrigeration) service should NOT be trying to do it. We had to reduce the useage of R12 because of this exact kind of problem, and the EPA restricted purchase to only those trained and equipped to properlly service the systems. They should have done the same thing with R134. It's a greenhouse gas, that will contribute to global warming just like carbon dioxide will. First and foremost, your AC system has a leak. You need to find and repair that leak. The coolant fan operation is controlled by a switch (sensor/transduecer) on the high side, and is pressure(temperature) related. With gages hooked up, and the correct scan tool to monitor the inputs to the PCM, (or AC control head depending on the exact system in your car) a technician can easily determine why the fans are not cycling, or if they in fact should not be depending on conditions. In fact, many of the systems have two speed fans, and the operation of the different fan speeds will vary because of ambient temperatures and system heat loads.

The A/C relay on your Honda, like most vehicles today, is computer controlled. The relay will have electrical power at two terminals of the relay with the key on and power at only one terminal with the key off. If there is no electrical power present at the relay, then you have to inspect the fuses. There are two fuses for the relay. One can be found in the under dash fuse panel. It will be a 7.5 amp fuse and will be located in position #6 of the fuse panel labeled A/C clutch relay/cooling fan relay. The other fuse is located in the under hood relay and fuse box. This is a 15 amp fuse and will be in position # 34 and labeled condenser/fan. If both fuses are good and there is electrical power to two of the terminals at the A/C compressor clutch relay, then you have a control problem. It could be as simple as a bad relay or the A/C system is low in charge. The A/C system has a pressure switch that stops the operation of the A/C compressor if the charge of refrigerant in the system becomes inadequate, too low. This is done to prevent damage to the compressor. To diagnose a control problem will require more specialized equipment, higher level of training and knowledge for diagnosis. At this point I would suggest that you involve a repair facility to perform this diagnosis.

Eddie, with your experience I won't go over the obvious things that could be causing the issue. It is possible you don't have a leak but still be low on refrigerant. Proper pressures don't just permit proper heat removal at the evaporator but also serve to keep the compressor cool and to keep the oil where it belongs. If your refrigerant charge was really low (as would an over charge), the unit could have pumped oil through the system. This would have decreased the inside diameter of the refrigeration circuit throughout the system. It would also act as an insulator to inhibit proper heat transfer. Once you charged the system, the oil worked it's way back to the compressor and now the inside diameter of the tubing is larger. If you check the charge, it may just need additional topping off. To do a good charge on a system, one should look at amperes, temperature differences between suction and high side lines as well as head and suction pressure. I personally also use an electronic sight glass to further help in a good and efficient charge. I'm not saying this is your exact problem because the expansion valve and fan speed can be the culprit too. But, I've trouble shot enough problem units through the years where what I described has been a factor. I've also seen this happen on units where air has gotten into the system where the technician forgot to purge their lines. The moisture collects as ice at the metering device and then goes through a melting and blocking cycle that never allows the evaporator to completely do it's job. Also, an overcharge can cause it. As you know but I'll mention for the sake of those that don't...a refrigerant charge peaks out and plateaus. Adding more refrigerant then starts a drop in the cooling capacity as well as causing other damage like bent valves in a reciprocating compressor or damaged pistons.

Please forgive my haste in answering and not trying to be too wordy. You're correct, under normal conditions, if there is no air flow through the evaporator, it will begin to ice up. I guess my focus is on the impression the unit may be overcharged. Once the works are hosed up, I didn't think it would do much good to discuss the proper operations of the unit. I am in favor of the pump-down method mentioned however, not all residential units have the valves to allow you to do that. If enough air is not moving through the coil, there will be a drop in the pressure and there will be a tendency to overcharge. This will inhibit the diagnosis for this particular unit...i.e overcharged or undercharged. As you know, as you add refrigerant to a system it reaches a peak cooling plateu when properly charged. As more refrigerant is added, cooling starts to drop (temperature rise) since saturation and evaporation appear later in the coil and the temperature rises. Liquid refrigerant can begin to enter the compressor and migrate into the oil and can also begin to enter the suction side of the compressor. If the compressor attempts to compress the liquid (which it can't) the breaker will trip or, the compressor will go out on overload due to excessive amperage draw...if you're lucky, before it does much damage to the compressor or valves. The rising oil (from overcharge) or splashing (due to undercharge) can enter the intake also, creating the same conditions as liquid refrigerant. Perhaps one can be lucky and the condition that is caused by this situation is less damaging (to some extent) but will cause the evap. pressures to rise...a reed valve not completely closing due to liquid caught between it and the seat. If the reed valves are not damaged, they are weakened. Yes, the oil does eventually return to the compressor. However, in this case (grossly overcharged), if it is continually being pumped through the system, it reduces the inside diameter of the tubing and, at the same time inhibits the tranfer of heat and there is still the chance of liquid refrigerant or oil entering the compressor. At this point, to assure a proper diagnosis, this particular unit must be done by the book. I'm not an extremist so, I don't want to say this unit needs a new compressor (although it very well may). I also don't want to say it is exteremly overcharged. Before I would condemn it, I would make sure BOTH coils are cleaned. I would connect my ammeter to the common on the compressor. I would connect my high and low side guages. I would connect thermometers to the high and low side lines. I would measure the ambient temperature. Using the manufacturers chart for that unit, I would determine what the pressures should be. (so far, we're talking 5 minutes work unless coils, filters or fans need cleaning). I'd then start my diagnosis from there as to whether the unit is over charged, under charged or need replacing. Anyone who cares to know how I would further diagnose the unit, please feel free to send me an email.