Truck Component
RigMaster Power APU
RigMaster (Hennessy Industries) · Apu · Diesel APU (value tier)
Class 8
In production
Apu
Manufacturer
RigMaster (Hennessy Industries)
Category
Apu
Subtype
Diesel APU (value tier)
Class
Class 8
What this component does
RigMaster is a value-tier diesel APU — competes with Thermo King TriPac and Carrier ComfortPro at lower price point. Similar functionality (diesel engine + generator + climate control) but smaller market share. Strong in owner-operator + small-fleet market where upfront cost matters more than dealer-network breadth.
Specifications
- Manufacturer
- RigMaster (Hennessy Industries)
- Category
- Apu
- Subtype
- Diesel APU (value tier)
- Truck class
- Class 8
- Production
- 2005–present
- Applications
- Sleeper cab APU — budget-conscious owner-operators + small fleets
Design and engineering
Diesel engine + generator architecture similar to TriPac and ComfortPro. EPA-compliant.
Generations
- RigMaster Power (2005–present)Continuous production with EPA compliance updates.
Reliability and longevity
Decent reliability for the price tier. Service network smaller than Thermo King or Carrier.
Common problems
Same family of diesel APU issues — engine wear, emissions service. Smaller service network = longer waits in some regions.
Maintenance schedule
Per RigMaster schedule.
Pros and cons
Pros
- ✓15-25% cheaper than TriPac or ComfortPro
- ✓Same functional design
- ✓Owner-operator friendly
Cons
- !Smaller service network
- !Less consistent QC vs Thermo King/Carrier
- !Lower resale value
Trucks that use this component
Other Apu components
- Carrier ComfortPro APUCarrier Transicold
- Espar Airtronic D2 (diesel-fired bunk heater)Espar (Eberspächer)
- Idle Free Electrified APU (battery-powered)Idle Free Systems
- EV-eAUT Battery Electric APU (next-gen)Multiple (Espar, Carrier, Volvo Group)
- Thermo King TriPac Evolution (diesel APU)Thermo King (Trane Technologies)
Related
Frequently Asked Questions
What is an APU?
APU (Auxiliary Power Unit) is a small auxiliary engine or battery system mounted on a Class 8 sleeper-cab tractor that provides cab heating, air conditioning, and 110V electrical power without running the truck's main engine. RigMaster is a value-tier diesel APU — competes with Thermo King TriPac and Carrier ComfortPro at lower price point. Similar functionality (diesel engine + generator + climate control) but smaller market share. Strong in owner-operator + small-fleet market where upfront cost matters more than dealer-network breadth.
How much does an APU save in fuel?
A diesel main engine consumes 1.5-2.5 gallons per hour at idle. A diesel APU consumes 0.2-0.4 gallons per hour — saving 1.5-2 gal/hour. At \$3.50/gallon diesel and 1,500-2,000 hours of annual idle time, an APU saves $5,250-\$14,000 per year per truck. Payback period: 8-24 months depending on usage. Electric APUs save additional fuel because they consume zero diesel during operation (battery is charged while driving).
Is an APU required by law?
No — APUs are not federally required. However: most US states have anti-idling regulations limiting how long a truck can idle its main engine while parked (typical limit 5-30 minutes depending on state). California, Texas, New York have the strictest rules. APUs provide the cab climate control that anti-idling rules would otherwise eliminate. Many fleets and owner-operators consider APUs essentially mandatory for over-the-road sleeper-cab operations.
How much does an APU cost?
New diesel APU (Thermo King TriPac, Carrier ComfortPro): \$9,000-\$13,000 installed. New battery-electric APU (Idle Free, EV-eAUT factory-fit): \$8,000-\$15,000 — slightly cheaper now that battery costs have come down. Diesel-fired bunk heater (Espar Airtronic D2 — heat only, no A/C): \$1,500-\$2,500. Used APUs (5-year-old): 40-55% of original price. Theft is a recurring fleet problem — APUs are easy to steal from parked trucks and have a strong used market.
How long does an APU last?
Diesel APU service life: 12,000-15,000 operating hours before major overhaul. Battery-electric APU: 5-8 years before battery degradation requires replacement ($3,000-$6,000). At 1,500-2,000 hours per year, diesel APUs last 6-10 years before major service; electric APUs last 5-8 years before battery replacement. Both require regular PM.
Diesel APU vs electric APU?
Diesel APU (TriPac, ComfortPro, RigMaster): Unlimited duration, works in any climate, mature technology. Drawbacks: EPA Tier 4 emissions complexity, \$0.20-0.40/hour diesel cost, ~400 lb weight, theft target. Electric APU (Idle Free Lithium, OEM factory-fit): Zero emissions, zero fuel cost, quieter, lower maintenance. Drawbacks: 8-10 hour duration, cold-weather range limits, battery replacement expensive at end-of-life, requires depot 110V/3-phase for full recharge. California ACT mandates and emissions trends favor electric for long-term fleet planning.