Carrier Performance TP-PRH-A Installation Instructions Manual page 63

E5 - - If Thermidistat Control cannot properly read humidity, E5 will be displayed.
Replace Thermidistat Control. If both Humidify and Dehumidify have been set to
OF, the humidity value will be shown as "- - - - " when viewed from the humidity
menu, but no E5 will be shown in the display.
Table 4 can be used as a troubleshooting tool for determining which outputs will be
active for a particular configuration and each operating mode.
When replacing a failed component such as an equipment control module or a
display module, the installer should replace both parts as a matched set. It is very
easy to accidentally mix an A/C or HP display with a PRH equipment control
module. When this happens, some functions appear in the setup while others do not.
This can be very confusing to troubleshoot. Verify that both parts have the same
model and serial number when troubleshooting the thermostat.
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