Why doesn't my HVAC system turn on immediately when placed in COOL or HEAT mode?

The Zen Thermostat has built-in HVAC cycle delays. We have found that the most damage to an HVAC system occurs at the cycle startup, to reduce the overuse of the cycle startup the Zen Thermostat delay is set as a basic configuration setting. It is possible to change the time of the delays via the “Advanced Configuration Settings” of the Zen Thermostat.

For a more detailed description of the HVAC cycle delays please see the attachment below.