Mastercool 98061 — Digital Vacuum Gauge

As a professional technician, the assurance of a deep vacuum on a system is imperative. The main problem with many small handheld units is their inaccuracy and durability. Although the thermocouple sensor has been proven to be much more accurate and durable than the thermistor type, the problem has been the inconvenience of a cumbersome tabletop unit. Mastercool is introducing a handheld unit using thermocouple technology. This vacuum gauge has been designed with the technician's field environment in mind, allowing for self-calibration and a sensor that will not be damaged by small mists of oil. The Mastercool unit allows for a target vacuum range to be programmed with a light sensor indicator. Now you have the freedom to continue with your other work and come back to the system once you see the indicator light signalling your target vacuum.

Key Features

• Thermocouple Sensor: More accurate and durable than thermistor type
• Handheld Design: Portable field use without tabletop inconvenience
• Self-Calibration: Ensures accuracy in field conditions
• Oil Mist Resistant: Sensor not damaged by small oil mists
• Programmable Target Vacuum: Set desired vacuum level
• Light Sensor Indicator: Visual alert when target reached
• Hands-Free Operation: Continue other work whilst evacuating
• Spiral Cable: Extends to 6.5 feet (2.6 metres)
• Multiple Units: Displays in Micron, Torr, mTorr, mmHg, mBar, Pa
• High Accuracy: ±5% of reading from 100-1 Micron

Technical Specifications

• Model: 98061
• Type: Digital vacuum gauge with thermocouple sensor
• Response Time: 250 mSec
• Sensor: Thermocouple sensor
• Sensor Cable: Spiral cable extended to 6.5 feet (2.6 metres)
• Connection Fitting: 1/4" flare female adapter
• Operating Temperature: 32 to 120°F (0 to 45°C)
• Power: 9V DC battery (AC/DC adapter optional)
• Battery Life: 36 hours
• Low Battery Indicator: Special icon on LCD
• Vacuum Units: Micron, Torr, mTorr, mmHg, mBar, Pa
• Accuracy Range:*
  • ATM-1000 Microns: ±10% of reading
  • 1000-100 Microns: ±7% of reading
  • 100-1 Micron: ±5% of reading
• Package: Blow-moulded case
• Weight: 0.8 kg
• SKU: 98061
• HS Code: 84189910

* Unit accuracy refers to sensor specifications and is based on optimal laboratory conditions. Field operations may greatly deviate from these levels.

Also Available

• 98061-C — Digital Vacuum Gauge packaged in a clamshell

Optional Accessories

• 98061-SENSOR — Replacement Sensor for 98061
• 99334-110 — 110V AC/DC Adapter
• 99333 — 1/4" FL-M x 1/4" FL-M x 1/4" FL-F Tee

Applications

• HVAC/R system evacuation verification
• Deep vacuum measurement
• Refrigeration system dehydration
• Automotive A/C evacuation
• Commercial refrigeration installation
• Heat pump installation
• System commissioning
• Post-repair evacuation verification

Why Thermocouple Technology?

Thermocouple sensors offer significant advantages over thermistor-type sensors:

• More Accurate: Proven superior accuracy in vacuum measurement
• More Durable: Longer service life in demanding field conditions
• Oil Resistant: Not damaged by small oil mists from vacuum pumps
• Field Reliable: Consistent performance in real-world conditions
• Professional Standard: Preferred technology for accurate vacuum measurement

Benefits

• Handheld Convenience: Portable design eliminates tabletop unit inconvenience
• Programmable Target: Set desired vacuum level and walk away
• Light Indicator: Visual alert when target vacuum reached
• Self-Calibration: Maintains accuracy in field conditions
• Oil Mist Resistant: Reliable operation near vacuum pumps
• Multiple Units: Display in preferred measurement units
• High Accuracy: ±5% at deep vacuum levels (100-1 Micron)
• Long Battery Life: 36 hours of operation
• Extended Cable: 6.5 feet spiral cable for convenient positioning
• Professional Quality: Built for daily workshop use

Perfect For

• HVAC/R service technicians
• Automotive A/C specialists
• Commercial refrigeration installers
• Residential A/C installers
• Workshop and service centres
• Mobile service operations
• Fleet maintenance facilities
• Professional vacuum verification operations

How to Use

1. Connect 1/4" flare fitting to vacuum pump or system
2. Power on gauge and allow sensor to stabilise
3. Select desired vacuum units (Micron, Torr, etc.)
4. Programme target vacuum level
5. Start vacuum pump and begin evacuation
6. Monitor vacuum level on LCD display
7. Light indicator will signal when target vacuum reached
8. Verify vacuum holds (decay test)
9. If vacuum holds, system is ready for charging

Why Deep Vacuum Matters

Achieving deep vacuum (below 500 microns) is essential for modern HVAC/R systems:

• Moisture Removal: Water boils at lower temperatures under vacuum
• System Protection: Moisture causes acid formation and compressor damage
• Performance: Air and moisture reduce efficiency and cooling capacity
• Refrigerant Purity: Non-condensables contaminate refrigerant
• Warranty Compliance: Many manufacturers require deep vacuum
• Professional Standard: Industry best practice for quality installations

Programmable Target Vacuum

The 98061's programmable target feature revolutionises evacuation workflow:

• Set Target: Programme desired vacuum level (e.g., 500 microns)
• Start Evacuation: Begin vacuum pump operation
• Continue Other Work: Technician free for other tasks
• Light Indicator Alerts: Visual signal when target reached
• Verify and Charge: Return to system for decay test and charging

This hands-free operation significantly improves productivity, allowing technicians to work on other tasks whilst systems evacuate.

Self-Calibration Feature

The self-calibration capability ensures accuracy in field conditions:

• Compensates for environmental variations
• Maintains accuracy over time
• No need to return to laboratory for calibration
• Reliable measurements in real-world conditions

Maintenance

• Sensor: Replace when accuracy decreases (use 98061-SENSOR replacement sensor)
• Battery: Replace 9V battery when low battery icon appears
• AC/DC Adapter: Optional 99334-110 adapter for continuous operation
• Storage: Store in blow-moulded case when not in use
• Cable: Inspect spiral cable for damage regularly
• Calibration: Use self-calibration function periodically

Accuracy Range Explained

The 98061 provides different accuracy levels across its measurement range:

• ATM-1000 Microns (±10%): Initial evacuation phase
• 1000-100 Microns (±7%): Intermediate evacuation
• 100-1 Micron (±5%): Deep vacuum verification (most critical range)

The highest accuracy at deep vacuum levels (±5%) ensures reliable verification of proper system evacuation.

Safety Guidelines

• Ensure proper ventilation when evacuating systems
• Wear safety glasses when working with pressurised systems
• Follow proper refrigerant handling procedures
• Do not exceed operating temperature range (32-120°F)
• Replace battery in safe environment
• Keep sensor away from excessive oil contamination

Professional Quality: Mastercool vacuum gauges are built to professional standards for accurate, reliable deep vacuum measurement in demanding HVAC/R service environments. The 98061 digital vacuum gauge features thermocouple sensor technology, programmable target vacuum with light indicator, self-calibration capability, and handheld convenience for professional evacuation verification operations. Packaged in a blow-moulded case.