Problem Solving (p. 65)

You should expect a hot discharge hose, condenser, and receiver-drier. A problem is indicated if it is hotter than normal. Possible causes are overcharge, restricted condenser, missing condenser seals, and contaminated refrigerant; further test are needed.

Problem Solving 1 (p. 90)

The oily dirt indicates a probable refrigerant leak which is a bad sign.

Problem Solving 2 (p. 97)

The hissing sound is refrigerant passing through the orifice tube as the high and low pressures equalize. It is normal, and there is no problem..

Problem Solving 3 (p. 108)

The short cycles along with a non-working A/C system indicate a very low refrigerant charge. Checking refrigerant pressures and the system temperatures should confirm this problem.

Problem Solving (p. 120)

Poor heater output is often caused by engine coolant that is not hot or poor flow though the heater core. To confirm these possibilities, check the coolant temperature to make sure it is hot and the temperature of the heater hoses. Both hoses should be hot with the return hose a little cooler.

Problem Solving 1 (p. 134)

Case 1: If the A/C air discharge is from the defroster ducts, there is a mode door failure, and it is defaulting to defrost. If this is a vacuum-operated system, there is probably a vacuum loss or severe vacuum leak. Check the vacuum supply to the control head. If the blower has no High Speed, the high blower relay has failed. Check the relay for proper voltage at the different terminals.

Case 2: This system is defaulting to defrost. It has a problem in the vacuum supply circuit. Inspect the vacuum check valve and reservoir.

Problem Solving 2 (p. 143)

If the air discharge is not cold, either the control head temperature setting is set too high or the A/C is not working. The temperature setting can be read on the control head. You can confirm A/C operation by looking for compressor operation and feeling the suction line; it should be cold.

Problem Solving 1 (p. 179)

Refrigerant pressure of 10 psi relates to a temperature of about 6^o F (-19 ^o C); normal pressure for a system that is not running should in the 60-80 psi range. This system probably has a low refrigerant charge.

Problem Solving 2 (p. 195)

If the TXV does not respond to thermal bulb temperature changes, it is bad. High low side pressure can be caused by a TXV that is stuck open. High low side pressure can also be caused by a restricted suction line or a faulty compressor.

Problem Solving (p. 266)

The high pressures and noisy compressor operation are being caused by the contaminated refrigerant. You should recover the refrigerant and send it off for recycling or disposal. After evacuating the system and charging it with the proper amount of clean refrigerant, it should work properly.

Problem Solving 1 (p.336)

The burned valves and warped head were caused by overheating. As the engine is being repaired, all possible causes for overheating should be checked and repaired.

Problem Solving 2 (p.339)

Removing the thermostat is never a wise move. All possible causes for overheating should be checked.

Problem Solving 3 (p. 356)

Case 1: The coolant is old with worn out inhibitors, and the cooling system is dirty. The rust and residue are probably reducing heat transfer. This cooling systems needs to be cleaned, flushed, and then filled with new coolant.

Case 2: This is similar to Case 1 but more severe. There is a possibility of a combustion leak into the cooling system under heavy load. The recommendation would be the same as Case 1 with the addition of a check for combustion leaks.