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Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 8679
Experience:  Retired HVAC/ Electrical & Boiler contractor. Industrial
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Im getting a high limit error on my american standard

Customer Question

Im getting a high limit error on my american standard freemdim 90 furnance
JA: How old is the appliance? Have you gotten error messages before?
Customer: No, its was installed d in 1999
JA: Do you plan on doing the work yourself?
Customer: If easy fix yes or i call pros
JA: Anything else we should know to help you best?
Customer: If tried reseting by cutting power then restarting the burner wont come on
Submitted: 11 months ago.
Category: HVAC
Expert:  Phil replied 11 months ago.

Hello, look at the units wiring diagram glued inside the blower access cover, locate the HL or High limit switch on the diagram, then use that information to locate it on the furnace..

for a brief 2 minute test only, fit a jumper wire across the switch, if the furnace then fires properly order a new switch from

Do not run the furnace without the high limit switch wired properly,

We can go from here without a time limit, I am off to bed right now but will pick up your response first thing in the morning,