When a TEV sensing bulb detaches from the suction line, what are the expected pressure readings?

When a thermal expansion valve (TEV) sensing bulb becomes detached from the suction line, it results in the sensing bulb not accurately measuring the temperature and therefore the pressure of the refrigerant in the suction line. This detachment can cause the valve to remain fully open as it cannot sense the actual conditions of the suction line.

As a result, the increased flow of refrigerant that does not correspond to the evaporator's demand leads to an abnormal operating condition. Specifically, the suction pressure will rise above normal levels because the excess refrigerant is not being vaporized adequately in the evaporator, causing excessive saturation of the refrigerant in the suction line.

Simultaneously, the discharge pressure can also be high due to the compressor working to pump an abnormal amount of refrigerant out of the evaporator, leading to an increase in both suction and discharge pressures. This combination reflects that both readings are elevated due to the improper operation of the TEV in this scenario.