Orion Motor Tech OMT 4.5 CFM Single-Stage Vacuum Pump

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Product guide

Orion Motor Tech OMT 4.5 CFM Single-Stage Vacuum Pump

Orion Motor Tech’s OMT 4.5 CFM single-stage vacuum pump is listed for automotive AC and HVAC evacuation, with a 1/3 hp motor and a claimed ultimate vacuum of 37.5 microns. Its oil-level window and included oil are useful for service work, though buyers should account for mixed customer feedback about heat, reliability and oil needs.

At a glance

The listing claims compatibility with R12, R22, R134a, R410a and R502 refrigerants.
A sight glass and scale are intended to make oil-level checks easier.
The manufacturer describes an aluminum alloy casing, intake filter and oil-mist trap.
The listing presents uses beyond HVAC service, including vacuum packaging, wine degassing and thermoforming.

Price

$71.99Save 10%

Reference price: ~~$79.99~~

Price checked: Nov 12, 2026

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Pros and cons

Pros

The listed 4.5 cfm flow rate and 1/3 hp motor provide concrete performance specifications for comparing single-stage pumps.
Oil is listed as provided, and the pump has a sight glass and scale for monitoring the reservoir.
The listing names an adapter, Teflon tape and work gloves among the supplied accessories.

Cons

The stated duty cycle is 30 minutes, which may constrain uninterrupted operation.

Technical specifications

13 specifications

Identity
Brand	Orion Motor Tech

Pump performance
Pump type	Rotary Vane
Motor power	1/3 hp (248W)
Flow rate	4.5 cfm (7.6 m³/h)
Ultimate vacuum	37.5 Microns (5 Pa)
Duty cycle	30 min.

Ports, oil and power cord
Inlet ports	1/4 in. & 1/2 in.
Oil capacity	0.24 qt. (225 mL)
Oil provided	0.26 qt. (250 mL)
Cord length	4.6 ft.

Dimensions and installation
Dimensions listed	10.8 x 4.3 x 8.5 inches
Weight listed	10.78 pounds

Listed accessories
Provided accessories	1x 1/4" to 3/8" Adapter, 1x Teflon Tape, 1x Pair of Work Gloves

What to know before buying

Listing details to confirm

The listing gives conflicting dimensions and weight: its details section says 10.8 x 4.3 x 8.5 inches and 10.78 pounds, while the technical listing says 9.8×4.3×8.5 in. and 10.3 lb. Customer feedback also varies on durability and oil sufficiency, and reports the pump can get extremely hot. Treat performance and build claims as listing claims, not verified results.

Who is it for?

A good fit for

Automotive AC and HVAC users comparing a single-stage pump by listed flow rate, motor power and ultimate vacuum.
Users who want an oil-level viewing window and a small set of listed service accessories.

Less suited to

Buyers who need a pump for uninterrupted operation beyond the listed 30-minute duty cycle.
Buyers who require confirmed long-term reliability or consistently low operating temperatures.

Orion Motor Tech OMT 4.5 CFM Single-Stage Vacuum Pump · photo 2 — Additional product photo 2

Customer reviews on Amazon

4.4 / 5 · 1,064 ratings

5 stars75%75%
4 stars12%12%
3 stars4%4%
2 stars2%2%
1 star7%7%

Customer feedback highlights perceived quiet operation, suction and quick evacuation, while durability and oil sufficiency receive mixed reports. Some customers describe units failing after first use, and others report substantial heat during operation. These reports matter for buyers considering repeated or extended service work, especially alongside the listed 30-minute duty cycle. Feedback is not a performance test or confirmation of the manufacturer’s vacuum and flow claims.

Positive themes

Customers report quiet operation, strong suction and quick evacuation.

Negative themes

Some customers report that the pump gets extremely hot during operation.

Mixed feedback

Customer reports differ on durability and reliability, including both well-constructed impressions and early failures.
Customers disagree about whether the supplied oil amount is sufficient.

Frequently asked questions

What refrigerants does the listing name?

The listing names R12, R22, R134a, R410a and R502. Confirm suitability for your specific system and service procedure.

What accessories are specified?

The technical listing specifies a 1/4" to 3/8" adapter, Teflon tape and a pair of work gloves. The feature text also claims the package includes lubricating and absorptive oil.

How long is the stated duty cycle?

The listed duty cycle is 30 min. The source does not specify a cooldown interval.

Are the listed dimensions and weight consistent?

No. The details section lists 10.8 x 4.3 x 8.5 inches and 10.78 pounds, while another technical section lists 9.8×4.3×8.5 in. and 10.3 lb. Check the selected listing before relying on these measurements.