Upon arrival, system was operating in heating mode. Shortly after, system shut down on code 33 for limit circuit fault. Inspection of system shows that manifold gas pressure is at 3.7inwc. Blower speed is on medium and system has a clean filter. Upon initial test run of the unit, the system was operating with a very high temperature rise. This will cause shortcycling, and in turn, will also cause uneven heating of the house. Adjustments made are setting the gas pressure to 3.0inwc and increasing blower speed from medium to medium-high. This will also help with uneven heating of the house. With new adjustments, the system is operating within manufacturers specifications for temperature rise, gas pressure, and blower operation. No other issues are found or suspected at this time. Lower gas pressure will ensure longer run times. Increased blower speed will force more air to the second floor of the house. It is also recommended to turn the fan setting on the thermostat to "on." All three