Automotive Service Technician (AST)

Fourth Period Package (24 Modules) Comments

Date: 2/10/2023 2:19:59 PM
Module: 090403c
Version: 24
Page: 37
Comment: When converting Fahrenheit to Celsius, the normal conversion (C=(f-32)*(5/9)) is used on every value. This is incorrect. When converting a temperature difference, C=F*(5/9) should be used instead. This applies to any temperature delta, but in this instance specifically superheat and subcooling. Example: figure 28 Evaporator has a saturation point of -15 F (-26 C), and a tailpipe temperature of 50 F (10 C) 50 – (-15) = 65 10 – (-26) = 36 Superheat is stated as “65 F (18 C)” (incorrect conversion) Converting 65 using F*(5/9) results in approximately 36
Status: Approved for Review

Archived Comments

Year: 2019

11/15/2019 9:25:47 AM
Module: 090404b
Version: 3.0
Page: 23/27
Comment: When instructing theory lessons on hybrid operations and components, the module references the DC to DC converter several times, occasionally calling it an inverter. The inverter performs DC to AC functions, and vice versa, but the CONVERTER performs DC to DC functions. Unfortunately, with the terms converter and inverter both being used to describe the same component, a few students have brought in to my attention in confusion. They understand that the converter can be built into the inverter module, but require that separation of terms for clearer instruction. Thank you.
Status: Implemented