Thermo King Precedent S-600 Trailer Refrigeration Unit

The Thermo King Precedent S-600 is the model that replaced the SB line as Thermo King’s mainstream trailer unit, and the reason fleets moved to it is regulatory as much as mechanical. The S-Series meets EPA Tier 4 final and California Air Resources Board emissions certification without a diesel particulate filter — which matters because a DPF on a reefer is a maintenance liability. Reefer engines run light loads, frequent starts and low exhaust temperatures, exactly the duty cycle that clogs a filter and forces regeneration. Listed at $13,500. Thermo King calls the result an evergreen CARB solution — the certification does not lapse on a fixed schedule the way earlier ULETRU approvals did. Operators still have to register each TRU with CARB, pay the operating fee and renew the compliance label every three years. Precedent S-600 Specifications Type: single-temperature nose-mount trailer refrigeration unit Engine: Precedent S-Series, greater than 25 horsepower, Tier 4 final certified Emissions: EPA Tier 4 final and CARB ULETRU compliant, no DPF fitted Cooling capacity with ETV at 100°F ambient, high speed: 60,000 BTU/hr (17,584 W) at 35°F; 32,000 BTU/hr (9,378 W) at 0°F Evaporator: dual-speed induction fan, maximising airflow at both engine speeds Capacity control: electronic throttling valve Condition: new and inspected used units available Price: $13,500 Where the Fuel Saving Comes From Thermo King quotes double-digit fuel savings over the SB generation, and it is not one change but several. The dual-speed evaporator fan stops the unit wasting engine power moving air it does not need to move. The ETV holds a tighter band around setpoint so the compressor loads and unloads less. And the engine itself is tuned for the light-load, frequent-restart pattern a reefer actually sees rather than the steady-state duty a generator sees. Applications Long-haul frozen and chilled freight in 48 and 53 foot vans, grocery and foodservice distribution, and any operation that runs into or through California and needs certainty about compliance. Fleets replacing SB-230 or SB-210 units usually land here. S-600, S-700 or C-600? The S-700 is the higher-capacity model — 68,000 BTU/hr at 35°F against the S-600’s 60,000 — for heavier pull-down and 53 foot vans running frozen. The C-600 shares the platform at a lower capacity point. If your loads are pre-chilled and your doors stay shut, the S-600 is enough; if you load warm and run deep-frozen, buy the capacity. Freight and Fitting Ships on a flatbed with forklift loading at both ends; freight is quoted to your delivery ZIP code. Installation on a trailer bulkhead should go to a Thermo King dealer or an experienced reefer shop. Contact us for engine hours, availability and a delivered price.