COMSTAR 45-005 Mineral Refrigeration Oil Gallon Sus 024924450055 C-4/GS 68/300 Compressor

( Brand: Comstar ), ( Manufacturer Part Number: 45-005 ), ( Part Type: Oil Compressor ), ( Unit Type: Gal ), ( Volume: 5gal. ), ( Package Quantity: Pack Of 1 ), ( Country Of Origin: United States ), ( UPC: 024924450055 )

Review COMSTAR C-4/gs Mineral Refrigeration Oil Gallon 68/300 Sus Compressor fits C-4 GS 300

The **ComStar 45-005 C-4/GS Mineral Refrigeration Oil**, a premium synthetic blend designed for high-performance refrigeration and air conditioning systems, represents the pinnacle of lubrication excellence for compressors operating under demanding conditions. Engineered specifically for use in systems utilizing **R-404A, R-507A, R-410A, R-407C, and other modern refrigerants**, this gallon-sized (128 oz / 3.78 liters) mineral oil is formulated to deliver outstanding thermal stability, oxidation resistance, and superior wear protection, ensuring prolonged compressor life and peak system efficiency. With a **viscosity grade of 68/300 SSU** (Saybolt Seconds Universal) at 100 F and 210 F respectively, this oil strikes an ideal balance between low-temperature fluidity and high-temperature film strength, making it perfectly suited for both commercial and industrial applications where temperature fluctuations and heavy loads are common. Its **C-4/GS classification** signifies compliance with stringent industry standards, including those set by the **ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers)**, ensuring compatibility with a wide range of hermetic and semi-hermetic compressors while minimizing the risk of oil breakdown, sludge formation, or seal damage. The oil s **mineral-based formulation** is carefully refined to provide exceptional lubricity, reducing internal friction within the compressor s moving parts and enhancing energy efficiency. Additionally, its **low volatility** minimizes oil loss through evaporation, reducing the need for frequent top-ups and extending the intervals between maintenance cycles. Whether deployed in large-scale industrial refrigeration units, commercial cold storage facilities, or high-capacity HVAC systems, this oil s robust performance characteristics make it an indispensable choice for operators seeking reliability, longevity, and operational cost savings. Backed by ComStar s reputation for quality and innovation, the 45-005 C-4/GS oil is not merely a lubricant it is a strategic investment in system integrity and performance.

### **Pros and Cons of Buying ComStar 45-005 C-4/GS Mineral Refrigeration Oil (68/300 sus for Compressor)**

1. **Compatibility with Compressors** This oil is specifically formulated for **C-4 and GS-type refrigeration compressors**, ensuring proper lubrication and performance. It is designed to work well with **mineral-based refrigerants** commonly used in older or industrial systems.

2. **High Viscosity Index (68/300 sus)** The **68/300 sus viscosity** provides stable lubrication across a wide temperature range, reducing wear on compressor components and improving efficiency in both cold and warm operating conditions.

3. **Mineral-Based Formulation** Mineral oils are widely used in refrigeration systems due to their **cost-effectiveness, availability, and compatibility** with many refrigerants (though they may not be suitable for newer synthetic or POE-based systems).

4. **Good Thermal Stability** The oil resists breakdown at high temperatures, helping to extend the life of seals, bearings, and other moving parts in the compressor.

5. **Widely Available & Cost-Effective** As a standard mineral oil, it is **easily sourced** from most industrial suppliers and is generally **less expensive** than synthetic alternatives.

6. **Proven Performance in Older Systems** If your compressor is **legacy or non-hermetic**, this oil is a reliable choice, as it has been used successfully in many traditional refrigeration applications.

---

1. **Limited Compatibility with Modern Refrigerants** This is a **mineral oil**, which is **not compatible** with **HFO (hydrofluoroolefin) or POE (polyol ester) refrigerants** (e.g., R-1234yf, R-449A). Mixing mineral oil with these refrigerants can cause **seal damage, reduced efficiency, or system failure**.

2. **Environmental & Regulatory Concerns** Mineral oils are **not biodegradable** and may pose environmental risks if spilled. Some regions have **restrictions on their use** in new systems due to sustainability regulations.

3. **Potential for Contamination** Mineral oils can **absorb moisture and acids** over time, leading to **oxidation and sludge formation**, which may clog filters and reduce system efficiency.

4. **Higher Maintenance Requirements** Compared to synthetic oils, mineral oils may require **more frequent oil changes** to prevent degradation, increasing long-term maintenance costs.

5. **Not Ideal for High-Temperature or High-Pressure Systems** While it performs well within its specified range, **extreme operating conditions** (very high temps or pressures) may accelerate oil breakdown.

6. **Potential for Leakage & Spillage Issues** Mineral oils can be **sticky and prone to leaks**, especially in older or poorly sealed systems, leading to waste and potential contamination.

---

The **ComStar 45-005 C-4/GS mineral refrigeration oil (68/300 sus)** is a **reliable, cost-effective choice for older or traditional refrigeration compressors** that use **mineral-compatible refrigerants** (e.g., R-12, R-22, R-502). It provides **good lubrication and thermal stability** for systems where it is properly specified.

However, if your system uses **modern refrigerants (R-134a, R-410A, R-449A, R-1234yf, or POE-based oils)**, this oil **should not be used**, as it will cause **compatibility issues and potential system damage**.

- Your compressor is **C-4 or GS-type** and designed for **mineral oil**.

- You are working with **legacy refrigerants (R-12, R-22, R-502)**.

- You need a **budget-friendly, widely available lubricant** for an older system.

- Your system uses **HFO (R-1234yf), POE, or synthetic refrigerants**.

- You are dealing with a **new or high-efficiency compressor** that requires **synthetic or ester-based oils**.

- You operate in a **strictly regulated or eco-conscious environment** where mineral oils are discouraged.

- For **modern systems**, consider **synthetic or POE-compatible oils** (e.g., **ComStar C-5, C-6, or C-7 oils**).

- If unsure about refrigerant type, **check manufacturer specifications** or consult a **refrigeration specialist** before purchasing.

Would you like guidance on identifying the correct oil for your specific compressor model?

Details:

Its compatible with HFC systems and ideal for maintaining system efficiency. Great Low-Temp Performance: designed for cold environments, it maintains fluidity and supports reliable system performance. Systems requiring mineral oil. Reliable Lubrication for A/C and Refrigeration Compressors: This Mineral Oil C-4 is designed to keep your refrigeration compressors running smoothly.

It provides superior lubrication, ensuring efficient operation even at high speeds and temperatures. Excellent Lubrication: This oil keeps A/C and refrigeration compressors running smoothly at high speeds temperatures. Compatible With HFC Systems: Works well with refrigerants for easy use in various systems. Easy Application: Simple to use, this oil helps reduce wear and extends the life of your compressors.

Low-temperature applications. Perfect For:: Refrigeration compressors. A/C compressors.

part #: 45005 price

• $174.90

specifications automobilefluids:

• for models: C-4, Gs, 300
• brand: Comstar
• mpn: 45-005
• part type: Oil Compressor
• unit type: Gal
• volume: 5gal.
• package quantity: Pack Of 1
• country of origin: United States
• upc: 024924450055

offer automobilefluids:

• availability: In Stock
• sold: 0
• started: March 16, 2026
• options: Ship-to-home

seller automobilefluids:

• rating: 100.0%
• # reviews: 64
• city: College Point, New York

returns automobilefluids:

• time: 30 Days
• paid by: Seller
• policy: Returns Accepted

shipping automobilefluids:

• class: Standard
• cost: $106.73
• carrier: USPS
• service: USPS Ground Advantage
• type: Calculated
• transit: 9-12 Days

general automobilefluids:

• Automotive Tools Supplies > Fluids Chemicals > Motor Oil
• condition: New

payments automobilefluids:

• other
• credit card: Visa
• wallet: Paypal

Comstar 45-005 Is Similar To:

• Comstar 024924603307 Water Absorber Improves Fuel Oil Performance And Tank Protection 1 Pint (28.2% similar) Water absorbed dispersing. Whether you're maintaining home heating oil, commercial fuel tanks, or industrial systems, this treatment keeps your cleaner and running smoothly. Prevents corrosion rust: protects fuel tanks and systems by reducing the risk of rust formation, helping to extend equipment ...(October 16th, 2025)
• Comstar 024924603451 Water Absorber Improves Fuel Oil Performance And Tank Protection 1 Gal (27.2% similar) Whether you're maintaining home heating oil, commercial fuel tanks, or industrial systems, this treatment keeps your cleaner and running smoothly. Cold weather protection for fuel systems. By preventing moisture buildup, this solution helps protect your system from rust, corrosion, and freeze-...(October 16th, 2025)
• Comstar 45-007 Polyol Ester Oil 32 150 Sus Poe Refrigeration For Hfc hcfc 1 Gal (48.4% similar) Industrial refrigeration units. Low moisture absorption: less gyroscopic than other oils, it reduces the risk of compressor burnout and helps maintain system integrity. Energy efficient: experience reduced energy consumption and lower operating costs with this high-performance lubricant designed for...(October 16th, 2025)
• Comstar 45-010 Polyol Ester Oil 68 300 Sus Poe Refrigeration For Hfc hcfc 1 Gal (48.4% similar) Residential cooling systems. Easy to use: ideal for quick top-offs, this oil saves you time and money without the need flushing. Versatile compatibility: suitable for HF, CFC, and CFC refrigerants, making it ideal a wide range of refrigeration systems. Stability: excellent thermal, oxidative, and ...(October 21st, 2025)
• Comstar 05-076 Heavy-duty Truck Wash Friction And Frictionless 1 Gallon 4 Pack (41% similar) Comstar truck wash detergent heavy duty exterior body cleaner 4/1 gallon powerful, USA made truck wash detergent formulated for both friction and friction less cleaning of painted bodies. This heavy duty, concentrated formula cuts through tough road grime, dirt, oil, and stains while rinsing clean ...(December 22nd, 2025)
• Comstar 45-526 Sae 20 Bearing Assembly Lube Oil For Bearings 8 Oz Pack Of 24 (32.5% similar) This expertly crafted anti-wear lubricant prevents build-up, letting your equipment perform smoothly for longer. Try it today. Ready for anything, anytime: perfect for industrial machines, heavy-duty equipment, and precision tools, our versatile machinery lubrication oil is your go-to smooth ...(December 31st, 2025)
• Comstar 45-014 Alkylbenzene Oil 32 150 Sus For A c And Refrigeration 5 Gal (48.7% similar) Its unique properties make it an essential component for both residential and commercial cooling systems. It reduces friction and wear on moving parts. This leads to lower operational costs. Its an essential component for both commercial and residential applications. The robust thermal stability of ...(January 7th, 2026)
• Comstar 45-106 Polyol Ester Oil Hmc 5 Gal For Hfc hfo Systems Rust And Corrosion Protect (45.8% similar) With advanced friction modifiers, anti-wear protection, and enhanced miscibility, this lubricant ensures smooth operation longer compressor life. Long service life: designed for extended fluid life, this anti-wear lubricant maintains stability in both high and low temperatures, reducing maintenance ...(March 11th, 2026)
• Comstar 45-750 Oil In 1-clear 5 Gal All-purpose Cutting For Threading And Machining (36% similar) Industrial and commercial threading tasks. Extend tool lifespan: protect your tools, dies, and chasers with advanced lubrication that minimizes wear heat buildup, keeping them in top condition longer. Premium cutting oil for sharp threads reliable performance: take your threading tasks to the next ...(March 17th, 2026)