Lennox Replacement Thermostats and High Limits

When control and efficiency are your top priorities for your HVAC system, consider the Lennox thermostats available at Parts Town. When you need temperatures to stay in the right range and not let spaces get too hot or cold, these parts are here to help. Check out our variety of Lennox thermistors here at Parts Town. We offer only genuine, OEM parts so you know that you can rely on them for maintenance and repairs. They will fit seamlessly with your system and keep your spaces at optimal temperatures.

What is The Difference Between a Thermostat and a Hi-Limit Switch in an HVAC system?

The thermostat and hi-limit switch fulfill different functions within an HVAC system. A thermostat is responsible for controlling the environment's temperature, turning the heating or cooling system on or off to achieve the temperature specified by the user. On the other hand, a hi-limit switch serves as a safeguard, designed to shut off the HVAC system should internal temperatures escalate beyond a predetermined limit, thus preventing overheating.

What are Signs That an HVAC Hi-Limit Switch has Tripped Or Failed?

When an HVAC hi-limit switch trips or fails, it often results in the heating system turning off before it reaches the desired temperature or not turning on at all. This situation usually signals that the system has become too hot, a condition that could stem from issues like airflow restriction, a dirty air filter or other mechanical issues.

Why is The HVAC System Not Maintaining The Set Temperature On The Thermostat?

HVAC systems that struggle to meet set temperatures can often be traced back to thermostats — whether they're miscalibrated, poorly located or simply too old and in need of a swap. Beyond thermostat-related issues, the root of the problem may be with the HVAC system itself, including filters choked with dirt restricting airflow, leakage in ductwork causing air to seep out or a mismatch between the system's capacity and the size of the space it's regulating.