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B-COOL 9RM | 12V & 24V DC Powered Roof Mount Air Conditioner

B-COOL 9RM | 12V & 24V DC Powered Roof Mount Air Conditioner

 Contact Us to Request Pricing

The B-COOL 9RM is a 12V and 24V DC-powered rooftop no-idle air conditioner built for large cab spaces — semi trucks, sleeper cabs, heavy equipment, and any application where you need serious cooling coverage with near-silent operation. At 38 dB it runs as quietly as the 6RM, but with a larger footprint and higher airflow designed to handle bigger interiors.

No engine idling. No shore power. No generator. The 9RM runs entirely off your 12V or 24V DC battery system — keeping operators cool, comfortable, and compliant with anti-idling regulations without burning a drop of fuel.

At 77 lbs with a 30.4 x 38.2 in footprint, the 9RM is the largest single-fan rooftop unit in the B-COOL lineup. It comes pre-charged and ready to install — cut the roof opening, bolt it down, connect to your battery, and go.
Technical Specifications

📄 Download Full 9RM Spec Sheet

Specification 12V 24V
Current Draw (Min – Max)30 – 70A8 – 38A
Evaporator Airflow350 m³/h350 m³/h
Noise Level38 dB38 dB
RefrigerantR134a, capillary tube systemR134a, capillary tube system
Roof Cut Size13.78 x 21.26 in13.78 x 21.26 in
Unit Weight77 lbs77 lbs
Exterior Dimensions30.4 x 38.2 x 7.9 in30.4 x 38.2 x 7.9 in
Standard Power Cable6m (20ft)6m (20ft)
Optional Power Cable10.5m (35ft), sold separately10.5m (35ft), sold separately

What's In The Box?
  • B-COOL 9RM Rooftop Air Conditioning Unit (pre-charged, ready to install)
  • Remote Control
  • Rubber Gasket
  • Support Brace x1
  • Decorative Panel (optional interior finish)
  • Install Screws & Hardware Kit
  • Standard Power Cable — 6m (20ft)

Unit comes pre-charged with R134a refrigerant. No vacuum pump or refrigerant equipment needed for installation.

Optional: 10.5m (35ft) power cable available separately from our Parts Department.
Installation Manual

📄 Download Full 9RM Installation Manual
https://cdn.shopify.com/s/files/1/0715/1140/8684/files/1._9RM_-_INSTALLATION_MANUAL_-_2026_-_FINAL.pdf?v=1772664592

The 9RM is a self-contained rooftop unit — compressor, condenser, and evaporator all housed in one unit that mounts on top of the vehicle. No refrigerant lines to run. No separate condenser to mount. The unit ships pre-charged with R134a and is ready to run straight out of the box.

Professional installation required.

Step 1 — Cut the roof opening
Cut a 13.78 x 21.26 in rectangular opening in the roof. Measure twice before cutting.

Step 2 — Prepare the mounting surface
Apply the rubber gasket and sealant around the opening to create a weatherproof seal.

Step 3 — Set the support bolts
Adjust the support bolts to the correct height for your specific roof thickness before setting the unit.

Step 4 — Mount the unit
Set the 9RM onto the roof opening and secure it with the included support brace.

Step 5 — Connect the control panel wiring
Run the control panel wiring through the roof and connect to the interior control panel.

Step 6 — Connect power
Run the power cable to your 12V or 24V battery bank. Connect positive first. The standard cable is 6m (20ft). An optional 10.5m (35ft) cable is available from our Parts Department if needed.

Step 7 — Set low voltage protection
Before first use, program the voltage cutoff to protect your battery system:

  • 12V systems: set cutoff between 9V – 12V
  • 24V systems: set cutoff between 19V – 24V

Step 8 — Finish interior
Install the optional decorative panel on the interior ceiling for a clean finish.

Step 9 — Power on
Turn the unit on and verify operation.
Operating Manual

📄 Download Full 9RM Operating Manual
https://cdn.shopify.com/s/files/1/0715/1140/8684/files/2._9RM_-_OPERATING_MANUAL_-_2026.pdf?v=1772664592

Inside Control Panel — 4 Buttons

  • Button A: Power on / off
  • Button B: Mode — cycles through Low / Medium / High / Powerful fixed-frequency cooling
  • Button C (▲): Increase airflow level
  • Button D (▼): Decrease temperature / adjust settings

Remote Control

Power on / off. Temperature range: 60.8°F – 89.6°F.

Cooling modes:

  • High — default 60.8°F, Level 6 airflow
  • Medium — default 78.8°F, Level 4 airflow
  • Low — default 82.4°F, Level 3 airflow
  • Auto — default 78.8°F, Level 4 airflow
  • Fresh Air — fan only, compressor off. Circulates and ventilates without active cooling. Useful for mild days or when you want airflow without drawing full power.

Airflow: 6 adjustable levels via remote or control panel.

Display button: turns the interior cab display on or off — useful at night in a sleeper cab.

Low Voltage Protection

The 9RM includes programmable voltage cutoff to protect your battery system from deep discharge.

  • 12V systems: set cutoff between 9V – 12V
  • 24V systems: set cutoff between 19V – 24V

When battery voltage drops to the cutoff threshold the unit shuts off automatically to prevent battery damage.
Who It's Built For

The 9RM is the right unit if:

  • You drive a semi truck, sleeper cab, or long haul truck with a large cab interior and need quiet, no-idle cooling that runs all night on battery without waking you up
  • You operate heavy equipment — excavators, bulldozers, cranes, mining equipment — where cab size demands more airflow coverage than a smaller rooftop unit can provide
  • You need an aftermarket rooftop air conditioner for a large cab vehicle and want near-silent operation at 38 dB
  • You're anti-idling compliant and need a DC-powered solution that runs entirely off your auxiliary battery system
  • You want more airflow than the 6RM (350 m³/h vs 310 m³/h) while keeping the same whisper-quiet 38 dB noise level
  • Your cab is too large for the 6RM but you don't need the dual-fan power of the 12RM

The 9RM uses a capillary tube refrigerant system rather than an expansion valve — a simpler, more robust design with fewer moving parts, well suited to the demanding environments of heavy equipment and long-haul trucking.

Applications

Trucking & Transportation — semi trucks, sleeper cabs, long haul trucks, day cabs, tanker trucks, flatbed trucks, livestock trucks — particularly for large cab anti-idling compliance and overnight rest

Heavy Equipment — excavators, bulldozers, wheel loaders, motor graders, cranes, mining equipment, forestry equipment — large cab coverage at near-silent operation

Agriculture — large cab tractors, harvesters, sprayers — long days in the field where quiet operation reduces fatigue over a full shift

Construction — site supervisors, crane operators, large equipment cabs on urban and remote job sites

Emergency Services & Military — large command vehicles, field operations vehicles, response units where quiet DC operation is required
FAQ

Does the 9RM work on both 12V and 24V systems?
Yes. The 9RM is available in both 12V and 24V configurations. Select your voltage when ordering. The unit is wired for one voltage — it is not a dual-voltage unit.

How quiet is 38 dB really?
38 dB is roughly equivalent to a quiet library or a soft whisper at close range. It is the same noise level as the 6RM and significantly quieter than the 5RM and X7RM (both 68 dB). For overnight use in a sleeper cab, 38 dB is barely noticeable.

What is a capillary tube system and why does it matter?
The 9RM uses a capillary tube refrigerant metering system instead of an expansion valve. Capillary tube systems have fewer moving parts, making them more robust and reliable in the vibration-heavy environments of heavy equipment and long-haul trucks. They are a well-proven technology in mobile refrigeration applications.

Does it come pre-charged?
Yes. The 9RM ships pre-charged with R134a refrigerant and is ready to install. No vacuum pump or refrigerant equipment needed.

What size hole do I need to cut?
13.78 x 21.26 inches. Measure twice before cutting.

Is this unit compliant with anti-idling regulations?
The 9RM runs entirely on DC battery power with no engine idling required, making it fully compatible with anti-idling laws and idle reduction programs across North America.

How does the 9RM compare to the 6RM?
Both run at 38 dB. The 9RM is larger and heavier (77 lbs, 30.4 x 38.2 in) with higher airflow (350 m³/h vs 310 m³/h) and a larger roof cut, designed for bigger cab spaces. The 6RM draws less power and is better suited for smaller to mid-size cabs.

How does the 9RM compare to the 12RM Dual Fan?
The 12RM Dual Fan has higher airflow (400 m³/h), more operating modes, and dual fans but runs at 48 dB and weighs 99 lbs. The 9RM is lighter, quieter, and simpler — the better choice when noise level is a priority over maximum features.

What battery bank do I need?
At 12V, the 9RM draws between 30 and 70 amps. For overnight use contact our technical support team to size your battery system correctly for your runtime requirements.

Is a longer power cable available?
Yes. A 10.5m (35ft) optional power cable is available separately from our Parts Department.

What if I need replacement parts?
All 9RM components are stocked with dedicated part numbers. Contact our Parts Department at adrian@dcpowersales.com or 778-679-4999.
Contact & Support

When you buy from B-COOL, you're not buying from an Amazon storefront with no support. You're buying from the team that wrote the installation manual, stocks the replacement parts, and answers the phone.

Sales & Inquiries
📧 sales@dcpowersales.com
📞 778-590-5000

Technical Support
📧 adrian@dcpowersales.com
📞 778-679-4999


Parts Available in Canada & United States. We stock all parts - compressor, control board, condenser fan assembly, evaporator, blower motor, louver motor, all hoses, hardware and more.
Why B-COOL Does Not List BTU Ratings

Every other brand lists BTU numbers. We don't, and here's why.

BTU ratings in the 12V and 24V air conditioner market are tested in controlled lab conditions and competitors go with their favourite testing company and tend to use those results that depicts them the "best". Real-world performance — inside a truck cab or RV sitting in the sun at 100°F+ — is a completely different story. The numbers you see on competitor listings are inflated, and we are not willing to publish figures that mislead the people who depend on this equipment to stay safe and productive.

Lower amp draw means longer battery runtime. For operators running on batteries overnight, during rest breaks, or in anti-idling zones, the 6RM stretches your power further than any other rooftop option in our lineup.

Compare All B-COOL Models

Model Noise Weight Airflow 12V Amps 24V Amps Special Features Availability
5RM 68 dB 40 lbs 400 m³/h 40 – 75A 11 – 40A Lightest rooftop, simplest install Available to Purchase Online
X7RM 68 dB 48 lbs 400 m³/h 40 – 75A 11 – 40A Cooling + PTC heating (4-season) Pricing Upon Request
6RM 38 dB 60 lbs 310 m³/h 30 – 60A 8 – 33A Quietest small rooftop, lowest amp draw, auto-swing louver Pricing Upon Request
9RM 38 dB 77 lbs 350 m³/h 30 – 70A 8 – 38A Capillary tube, large cab coverage Pricing Upon Request
12RV 28 dB 77 lbs 350 m³/h 30 – 70A 8 – 38A Quietest unit overall, RV square cut, internal filters Pricing Upon Request
12RM Dual Fan 48 dB 99 lbs 400 m³/h 35 – 85A 10 – 45A Dual fan, most modes, Hybrid Control Panel optional Pricing Upon Request
YTRM 48 dB 99 lbs 460 m³/h 35 – 85A 10 – 45A Highest airflow, yard truck built, ignition cut-off Pricing Upon Request
FLEX ST 48 dB 53 lbs 350 m³/h 35 – 65A 10 – 35A Flexible hose routing, split system Available to Purchase Online
FLEX QC 48 dB 53 lbs 350 m³/h 35 – 65A 10 – 35A Quick Connect, split system, 100A fuse included Pricing Upon Request
WMB ST 48 dB 44 lbs 350 m³/h 35 – 65A 10 – 35A Wall/side mount, no roof cut needed Available to Purchase Online
WMB QC 48 dB 44 lbs 350 m³/h 35 – 65A 10 – 35A Quick Connect, wall/side mount, 100A fuse included Pricing Upon Request

Not sure which unit is right for you? Contact our sales team at sales@dcpowersales.com or 778-590-5000 — we'll help you choose.

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