SSAC HVAC Timers & Controls

Protect your expensive HVAC equipment with SSAC timers designed specifically for heating, ventilation, air conditioning, and refrigeration applications. From compressor short-cycle protection to fan delay relays, SSAC has the right timer for your HVAC needs.

Need an HVAC timer? Talk to an expert:

262-252-1600

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HRDM HRDB Fan Delay Compressor

HVAC Timer Applications

⚠️ Compressor Short-Cycle Protection

Critical Application: Prevents compressor damage from rapid on/off cycling. When power is restored after an outage or thermostat satisfied, the timer delays compressor restart to allow pressures to equalize.

Why It Matters: Short-cycling can destroy a compressor in months. A $50 timer protects a $2,000+ compressor.

Recommended: SSAC delay-on-make timers (HRDM, KRDM, TDM series) with 3-5 minute delay

Fan Delay Relays (On & Off Delays)

Fan-On Delay (Heating)

Delays blower start until heat exchanger is warm. Prevents cold air blow. Use delay-on-make timer.

Fan-Off Delay (Cooling)

Keeps blower running after compressor stops to extract residual cooling. Use delay-on-break timer.

Heat Pump Defrost

Timed defrost cycles to remove ice buildup from outdoor coils. Critical for heat pump efficiency in cold climates.

Blower Motor Delay

Sequences blower start/stop with heating or cooling. Improves comfort and efficiency.

Anti-Recycle Timer

Prevents rapid recycling of equipment. Ensures minimum off-time between cycles.

Oil Burner Control

Pre-purge and post-purge timing for oil-fired heating systems.

Download HVAC Timer Catalog (PDF)

Popular SSAC HVAC Timers

Model Function Timing Range Application
HRDM Delay-On-Make 0.1 sec - 10 min Compressor protection, fan-on delay
HRDB Delay-On-Break 0.1 sec - 10 min Fan-off delay, run-on timing
KRDM Delay-On-Make 0.5 sec - 5 min Compact compressor lockout
TDM Delay-On-Make Multiple ranges 8-pin plug-in, easy replacement
HRDR Recycling Adjustable on/off Defrost cycling, duty control

Why SSAC for HVAC?

Protect Equipment

$50 timer protects $2,000+ compressor

10-Year Warranty

Outlasts the equipment it protects

Easy Installation

Standard mounting, clear wiring diagrams

UL/cUL Listed

Meets all safety codes

Related SSAC Products

Time Delay Relays
All TDR functions and models
Monitoring Relays
Voltage & phase protection
Full Catalog
All SSAC products with PDFs

Ready to Order SSAC HVAC Timers?

Same-day shipping. Expert support. 10-year warranty.

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Gross Automation - Your trusted SSAC Distributor Since 1992