Hummer H1 134A Specifications

• Production of the Hummer H1 civilian off-road vehicle began in 1992 and ran through 2006. The design was based on the M998 High Mobility Multipurpose Wheeled Vehicle (Humvee). There is concern over the air-conditioning system of this vehicle as it can depreciate over time. This can be improved by the use of the 134A in the air-conditioning system: 134A is a refrigerant also known as Forane. It can be used in various applications and as a component in refrigerant blends.The 134A in this system needs to be replaced occasionally.

134A

• The 134A has an average weight of 102 g/mol with a normal boiling point of -14 degrees Fahrenheit and a critical temperature of 214.1 degrees Fahrenheit. This refrigerant is designed to be compatible with many air-conditioning systems and medium temperature refrigeration systems. It has the least levels of toxicity and flammability and it is also non ozone depleting.

Hummer H1 Air-Conditioner

• The air-conditioning system in the Hummer H1 uses a compressor. This is a pump that compresses the gas, then allows it to expand and in this process it cools down. During expansion of the gas, the air is moved by a hose grid and undergoes subsequent cooling. The same process repeats over and over again. The charging of the 134A can either be done as a vapor or liquid and this is indicated in the vehicles recharging instruction. It can also be used to retrofit an already existing R12 system in the vehicle. In this retrofit, the existing lubrication must be replaced by Polyalkylene Glycol (PAG) oil. The compressor is found on top of the engine where it is held in by four bolts. There are two electrical connectors on it for the solenoid and the other is a pressure monitor. There are two service ports marked in red denoting high pressure and blue for low pressure. Low pressure is in the driver's side of the compressor and the high on the passenger's side.

134A Recharging

• The process of recharging the 134A requires the following tools: gauge set for the 134A; service port connectors with one high and one low side designed for the R134A ports, they attach to the red and blue hoses on the gauge; a R134A can tap that is attached to the yellow hose on the gauge set; a vacuum pump which also attaches to the yellow hose plus an ultraviolet dye lamp.

  On testing the system, the following results can be obtained for Low Side/ High Side/ Air Temperature:

  --- Low/ Low/ Warm: needs more refrigerant

  --- High/ High/ Warm: too much refrigerant

  --- High/ High/ Cool: air in the system

  --- Normal/ Normal/ Warm: moisture in the system.