- The HH12ZB180 Bryant Carrier Furnace Limit Switch is brand new and comes packed in a Bryant Carrier Factory Authorized parts box.
- The HH12ZB180 Bryant Carrier Furnace Limit Switch replaces old Bryant Carrier part numbers HH12ZA178, P331-2204 and P331-2223.
- The HH12ZB180 Bryant Carrier Furnace Limit Switch has a 3″ insertion depth.
- FYI: A furnace limit is a safety device that is used to cut the gas burners off if the furnace over-heats. If your furnace is going off on limit you might have an air flow problem like a dirty filter, dirty blower, slow blower motor (might need a new capacitor) stopped up evaportator coil or too much gas pressure. All of these can cause the furnace to over-heat and go off on limit. Many times when the furnace goes off on limit the fan blower will continuously blow because the furnace control board senses that the furnace has over-heated and needs to cool down. The only way to get the blower to cut off is to turn off the furnace with the power switch. You can test a limit with a volt meter to see if it is open or not. On most limits you should get 24 volts from each of the two wires on the limit to a good ground. The HH12ZB180 limit opens the circuit when the furnace reaches a temperature of 180 degrees F.