Chassis
Standard on All Models
- Monolithic, low carbon steel weldment – the heaviest constructed roasters in their class.
- Fully gusseted for dimensional strength and stability.
- Fully coated to prevent corrosion.
- Integrated double-walled roast compartment is heavily insulated which further converts the chassis into a thermal battery – storing heat, rather than wasting it.
- Materials in both the chassis and the roast compartment absorb heat more efficiently and release heat more consistently for increased stability of temperatures during profiling.
- Trapping heat = trapping noise. Ambient drum noise is limited to a whisper quiet 60 decibels making it easier to hear those early outliers before first crack
Drum
Standard on All Models
- Double-wall, stainless steel drums standard on every model. The heaviest, most-efficient drum design in the industry.
- Construction accuracy is machine trued to within +/- .025”.
- 3mm air gap between inner and outer drum diffuses heat more evenly throughout inner drum.
- Diffused heat at inner wall eliminates conductive roast defect, even at higher inlet temperatures.
- Dramatically increased thermal efficiency by storing & using heat, rather than quickly releasing.
- “Bomb proof” construction prevents warping due to operator error.
- Every model equipped with quick response, variable drum speed allowing the operator to achieve ideal bean loft and conductive vs. convective ratio. Result is the flexibility to profile batches from 20%-120% of listed drum capacity on most models.
Advanced Features
- Advanced drum gap adjustment mechanism is standard on roasters sized 1.5kg, 3kg, and larger making drum gap adjustments easier and more precise.
Fuel
Standard on all models
- Custom-designed, CSA Design Certified low loss gas train designed by Mill City Roasters and used exclusively in our roaster line-up.
- Custom burners designed specifically for coffee roasting.
- Burner layout is specific to each model to achieve optimal burner-to-drum relationship.
- Easy access, external shut-off valves on every roaster.
- Built-in temperature limitors to allow for safe operation.
- Built-in safety shut-off on pilot valve.
- Easy conversion from LP to natural gas.
Manual gas control models
- Standard on 500g, 1kg, and manual 3kg models.
- High precision CV needle valves.
- Precision analog gas gauge.
Advanced digital gas control models
- Standard on 2kg, 6kg and larger (available on 3kg).
- Digital electronic modulating valve offering greater control for your most challenging profiles in variable batch sizes.
- Fuel adjustments at the push of a button
Air & Exhaust
Standard on All Models
- Power-vented dual exhaust system standard on every model with fan placement designed to allow for easy cleaning and maintenance.
- Roaster exhaust fan is high pressure, high output 3-phase VFD speed
controlled with linear response curve for more predictable and more precise airflow control and roast profiles repeatability. - Cooling tray exhaust fan is a dedicated, high-pressure fan providing rapid cooling to stop roast progression once batch is dropped in cooling tray. Dual exhaust system allow for simultaneous roasting and cooling, reducing back-to-back batch times and increasing production to 4-5 batches per hour.
- All machines include face-mounted drum pressure gauge: 500g and 1kg analog magnehelic, all other machines digital differential pressure gauge. Drum pressure offers a diagnostic to verify airflow volume from batch to batch and between cleanings for greatest possible consistency of roast profiles.
- All models equipped with dedicated, off-board chaff filtering collectors
with easy access doors to aid in frequent clearing of chaff and completion
of safety checks. - Optional quick-release venting kits available for every model.
- Fully specified requirements for venting to termination including layout and cap recommendations.
Advanced digital control models
- Standard on 2kg, 6kg and larger (optional on 3kg).
- Fan adjustments at the push of a button
Datalogging
Standard on All Models
- All machines equipped with USB Modbus data-logging connection.
- All models include thermocouples to record bean temperature, environmental temperature and drum temperature.
- Additional thermocouple at the rear of the drum standard on 1.5kg, 6kg and larger (available on 3kg) to record energy input into the roasting system. This helps operators tune roaster for maximum efficiency and avoid heat defect.
- All models output constant transmission of thermocouple readings and fan speed.
- Additional constant transmission of drum speed, gas pressure, and charge, discharge, and cooling tray discharge events standard on 1.5kg, 6kg and larger (available on 3kg).
Advanced Features
- Control panel display of drum temperature, environmental temperature, bean temperature and input air temperature from rear of drum.
- Control panel display of auto start digital roast timer and digital gas
pressure display of setpoint and process values. - Control panel display of digital drum speed and fan speed setpoints.
- All models will be off-board automation capable via model year 2021
RoastPATH datalogging application expansion
Operator Assist
Standard on 2kg, 6kg and larger (optional on 3kg)
- Roast timer automatically starts when the drum is charged.
- Burners automatically extinguish when the drum door is opened and re-ignite when closed to automatically recover to preheat temperature for quicker recovery.
- Drum discharge automatically starts the cooling tray arms and exhaust fan.
- Cooling tray discharge automatically stops the exhaust fan.
- Stirring arms automatically stop when the cooling tray cover is opened to
prevent accidents. - Burner interlock alarm prevents operator from proceeding with the roast if the charging gate is open
Safety
Standard on all MCR Series roasters
- CSA Design Certified CSA 1.8 for US and Canada, IEC, CE, ROHS on all
roasters 30kg and smaller. - CSA/UL certified Honeywell automatic ignition controller
- All UL/CSA certified Delta PLCs and VFDs.
- CSA/UL certified motors, relays, switches, and wiring.
Food & User Safety on All Models
- Entire contact path of roaster (hopper, loading chute, faceplate, tryer,
drum, discharge gate, discharge chute, cooling tray cover, cooling tray
floor, stirring/mixing arms, cooling tray gate, cooling tray latch, cooling
tray gate) all custom fabricated with certified food grade stainless. - Optional loader assembly on 20kg models and larger.
- Teflon cooling tray wipers
- Heavy duty 5mm x 44mm Borosilicate sight glass
- Food service safe LED light.
- Food safe resin-impregnated tryer handle
- Stirring arms automatically stop when the cooling tray cover is opened
Install & Maintain
Standard on All Models
- Models are designed with off-board cooling fans and chaff collectors to
allow for easier moving, better access and easier maintenance. Off-board
components can offer more flexible layouts for users with space limitations. - Detachable control panels of models 20kg and smaller for moving components through standard size door openings. Removeable hoppers on all models.
- Adjustable leg heights on most components.
- Casters on 2kg and 3kg models to allow for easy moving.
- Venting kits available for most models to quickly connect components.
- Cooling trays on models 6kg and larger are detachable from roaster body via quick disconnect electrical and sensor connections. Separate components allow for easier shipping and moving.
- Wide access doors on all roasters for easy access to interior components.
- Cooling trays 6-60kg feature large, full swing, removable access doors on
both sides for easier cleaning. - Warranty