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I have a totaline signature P374-1800 ac/heat control device…

Customer Question
I have a totaline...

I have a totaline signature P374-1800 ac/heat control device (actually have three total devices) and the backlit is out. The a/c control is fine but the device is in a dark hallway spot and I need a flashlight to see to adjust the settings. Is the display backlight user accessible?

Contractor's Assistant: Did you double-check the thermostat's settings? And what about the filters?

I did check the settings for setting the display including the setting for the backlight (auto, on, or off). It was set to auto. I changed it to "on" and no change, the backlight remained off.

Contractor's Assistant: Do you plan on doing the work yourself?

Only if it is simple. If not, we will call our a/c service guy.

Contractor's Assistant: Anything else we should know to help you best?

Of our three units which we have had for about 8 yrs, this is the only time and only the one unit with a backlight problem. The manual explains how to change the backlight settings but not how to replace an LED or whatever.

Submitted: 11 months ago.Category: HVAC
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Answered in 11 hours by:
8/1/2017
HVAC Technician: airheatman, HVAC Technician replied 11 months ago
airheatman
airheatman, HVAC Technician
Category: HVAC
Satisfied Customers: 9,209
Experience: Furnace, A/C and heat pump specialist.
Verified

If backlight is not working and you have followed the steps below, thermostat may have to be replaced as the light is not field repairable. Do you at any tine see PF on screen?

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