Choosing The Right Timer Switch: HVAC Systems

Choosing the right TS Series model for your HVAC system comes down to function, timing range, and control voltage:

1. Identify your function

Does your system require a delay on start, off stop, or cyclic control?

2. Select the timing range

Match the timer’s range (e.g., seconds, minutes, hours) to your HVAC process duration.

3. Check control voltage

Confirm your supply matches one of the TS Series’ wide input ranges (12–240V AC/DC).

Timer Function by Application

Function Type	Timing Range	Control Voltage	Application
On-Delay	0.1s–100h	12–240V AC/DC	Delay fan/pump startup after power-on to avoid load spikes.
Off-Delay	0.1s–100h	12–240V AC/DC	Extend compressor run for cool-down to protect equipment.
Star-Delta	Adjustable 0.1–30s transition	24–240V AC/DC	Soft-start motors with timed sequencing to reduce inrush.
Asymmetrical	ON: 0.1s–100h / OFF: 0.1s–100h	12–240V AC/DC	Cycle fans, alarms, or lights on a repeatable schedule.
Mult-function	Selectable 0.1s–100h	12–240V AC/DC	Use flexible timing profiles for quick field reconfiguration.

Timer Model by Use Case

Scenario	Model	Use Case
The fan starts after the compressor engages	On-Delay: TS01, TS02, TS03	Prevents short cycling by delaying fan start
Air handling unit post-run cooling	Off-Delay: TS04	Keeps the fan running to remove residual heat
Dual-speed compressor startup	Star-Delta: TS05, TS06	Limits inrush current during startup
Condensate pump cycling	Asymmetrical: TS08	Repeats ON/OFF intervals automatically
Multi-zone timing needs	Multi-Function: TS07, TS09 (analog); TS7954, TS7957, TS7958 (digital)	Provides flexibility for varying HVAC logic

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