THERMO SCIENTIFIC F85938 (01) PDF DOCUMENT

The safety symbols on the THERMO SCIENTIFIC F85938 indicate the following:

DANGER (Exclamation point in triangle): Indicates a hazardous situation which, if not avoided, will result in death or serious injuries.

WARNING (Exclamation point in triangle): Indicates a hazardous situation which, if not avoided, could result in death or serious injuries.

CAUTION (Exclamation point in triangle): Indicates a hazardous situation which, if not avoided, could result in damage to equipment or property.

Hot Surface (Wavy lines in triangle): This symbol indicates surfaces which may become hot during use and may cause a burn if touched with unprotected body parts.

Electrical Shock Hazard (Lightning bolt in triangle): This symbol indicates situations where dangerous voltages exist and potential for electrical shock present.

Gloves Required (Gloved hand symbol): This symbol indicates a need to use gloves during the indicated procedures. If performing decontamination procedures, use chemically resistant gloves. Use gloves during daily usage.

Fire Hazard (Flame in triangle): This symbol indicates potentially hazardous situations, which if not avoided could result in fire.

DANGER:

Do not modify or use the THERMO SCIENTIFIC F85938 in a manner other than expressly intended. Modification could cause severe injury or death.

Do not modify or disconnect any safety features. Disconnection could allow the unit to become overheated and start on fire.

Do not use components or materials not specifically designed for this equipment. Using non-OEM parts could cause faulty readings, inoperable equipment, or temperature overshoot, leading to personal injury, death, or property damage.

Before using, determine the suitability and integrity of the product for the intended use and that the unit has not been altered.

WARNING:

Use appropriate Personal Protective Equipment (PPE) per local protocols.

Before maintaining this equipment, read the applicable SDS (Safety Data Sheets) provided with the unit.

CAUTION:

This product contains refractory ceramic fiber or other refractories which can result in the following:

• May be irritating to skin, eyes, and respiratory tract.

• May be harmful if inhaled.

• May contain or form cristobalite (crystalline silica) with use at high temperature (above 871°C / 1599.8°F) which can cause severe respiratory disease.

• Possible cancer hazard based on tests with laboratory animals. Animal studies to date are inconclusive. No human exposure studies with this product have been reported.

To avoid the spread of fire, do not place any materials on the top of the enclosure.

To avoid electrical shock:

1. This furnace must be installed by a licensed electrician and/or qualified craftsperson in accordance with all applicable National and local Electrical codes and requirements.

2. Disconnect power before servicing. Ensure the main circuit breaker at the rear panel is OFF.

3. Ensure that the furnace is not connected to the power supply prior to installing or removing the balance.

4. Ensure that the door switch is operating properly.

To avoid burns:

1. Do not touch the exterior or interior surfaces of the chamber or exhaust area when the chamber is hot. “Hot Surface. Avoid Contact with Chamber Area.”

To avoid personal injury:

1. Do not use in the presence of flammable or combustible materials, including cutback asphalts; fire or explosion may result. This device contains components which may ignite such material.

2. Refer servicing to properly trained, and qualified personnel.

3. Allow the furnace to cool to room temperature before performing any maintenance or servicing.

4. Failure to connect the exhaust port to an appropriate exhaust system will result in smoke and gases entering the work area.

5. This furnace contains refractory ceramic insulation which can produce respirable fibers and dust when handled. These fibers can cause irritation and can aggravate preexisting respiratory disease. The International Agency for Research on Cancer (IARC) has classified refractory ceramic fiber as possibly carcinogenic. After service, refractory ceramic fiber dust may contain crystalline silica, which may cause lung damage (silicosis) and which has been classified by IARC as a carcinogen.

Intended Use:

The THERMO SCIENTIFIC F85938 NCAT Asphalt Content Tester is an analyzer that determines the asphalt content of a sample by loss on ignition per standard methods. The asphalt sample is bathed in oxygenated air and weighed continuously throughout the ignition procedure. The software identifies the endpoint of ignition and indicates the completion of the test. Results are documented by a printer.

Non-Intended Use:

This furnace is not intended for the following:

• To heat up food.

• For drying or heat treatment of substances which release gases or vapors into the atmosphere that are flammable or dangerously explosive when mixed with air.

• Heat treatment of combustible dusts and fibrous materials.

• Cleaning glassware, such as rolling thin film oven bottles. Prior to ignition, the asphalt in these bottles will liquefy and may flow into the lower control section of this product, causing severe damage or fire.

Do not use this product for anything other than its intended usage.

The furnace of the THERMO SCIENTIFIC F85938 is heated to a setpoint temperature between 450°C and 550°C. A hot mix asphalt sample is weighed, divided, and placed in two screened baskets on a tray assembly. This assembly is placed on the furnace hearth tray, which is mounted on four ceramic support tubes connected to a digital balance platform. A blower draws ambient air through openings in the chamber floor, saturating the sample with oxygen to promote ignition and ashing. The released volatiles are further oxidized while passing through a ceramic filter heated to 750°C in an upper chamber. The exhaust is then directed to a louvered plenum, cooled with ambient air, and directed by the blower through the exhaust port to an outside exhaust system.

Category		Specification
Overall Dimensions CM (IN.)	Width	54.29 (21.375)
	Height	102.87 (40.500)
	Depth	65.09 (25.625)
Chamber Dimensions CM (IN.)	Width	35.56 (14.000)
	Height	35.56 (14.000)
	Depth	35.56 (14.000)
Weight KG (Lbs.)		137 (302)
Electrical Ratings	Volts	208
	Amps	28
	Watts	5757
	Freq.	50/60
	Phase	1
Chamber Temperature Ratings		100°C-650°C
Max. Sample Cap.		5 kilograms of asphalt sample.
Max. Operating Temp.	Chamber	650°C
	Filter	900°C
Maximum Program Run Time		255 minutes

Allowable Values for Selected Functions:

Function	Allowable Value
Chamber Set point	100°C-650°C
Filter Set point	0°C-900°C
Sample Weight	100g-5000g
Correction Factor	0.00-99.99
Wake up Time	0:00-24:00
Wake up Date	0.00 – 12.31
Inactivity Check	On/Off
Auto Shut down	On/Off
Beeper	On/Off
Serial Port Output	Continuous/Test Only
Chamber Calibration Offset	+50 to -50
Test Stability Threshold	0.01-0.5%
Intermediate Printing (Internal Printer)	On/Off

Default Values for Selected Functions:

Function	Default Value
Chamber Set point	538°C
Filter Set point	750°C
Sample Weight	1200g
Correction Factor	0.00
Wake up Time	5:00
Wake up Date	0.00
Inactivity Check	On
Auto Shut down	On
Beeper	On
Serial Port Output	Continuous
Chamber Calibration Offset	0°C
Test Stability Threshold	0.01%
Intermediate Printing (Internal Printer)	On

Operating: 17°C – 40°C; 20% – 80% relative humidity, non-condensing. Installation Category II (overvoltage) in accordance with IEC 664. Pollution Degree 2 in accordance with IEC 664.

Altitude limit: 2,000 meters.

Storage: 25°C – 65°C; 10% – 85% relative humidity.

1. Visually check for any physical damage to the shipping container. Remove the furnace from the container and inspect surfaces adjacent to any damaged areas. Retain damaged packing material and file a claim with the delivery carrier if damage is found.

2. Open the furnace door and carefully remove all packing material from inside the furnace chamber. Remove the four (4) screws securing the front display panel and open it. Vacuum the chamber and the balance support plate (beneath the chamber) to remove any insulation dust from shipment. Wear a dust mask and gloves while cleaning.

3. Remove the balance, ceramic posts, fuses, manual (or USB stick), and hearth tray from the shipping container.

4. Retain the original packaging material in case reshipment is necessary.

NOTE: The THERMO SCIENTIFIC F85938 is intended for permanent connection to mains power. This must be performed by a licensed electrician/qualified craftsperson in accordance with all applicable National and local electrical codes and requirements.

Each palletized furnace carton contains:

• 1 Asphalt Content Tester

• 1 Electronic Balance

• 1 Hearth tray, gray silicon carbide

• 8 Ceramic tube supports, Inside Furnace Chamber

• 1 Instruction Manual, Inside Furnace Chamber

• 6 Replacement Fuses

Accessory Kit Contents (Part # AY1087X1) – Two basket assemblies consisting of:

• 2 Basket Retainer Brackets (BC1087X9)

• 2 Transport and Catch Trays (TY1087X3)

• 2 Top Baskets (TY1087X4)

• 2 Bottom Baskets (TY1087X5)

• 2 Covers for Top Baskets (CV1087X7)

• 1 Transport Handle (HN1087X4)

• 1 Aluminum Cooldown Plate (SH1087X1)

• 1 Cooldown Safety Cage with HOT Sign (CS1087X5)

• 1 Face Shield with Head gear (AYX4)

• 1 Pair High Temperature Gloves (AYX5)

• 1 Can of Fan Motor Lubricant (AYX6)

• 1 Stainless Steel Basket Brush (AYX7)

• 4 Rolls of Thermal Printer Paper (PRX2)

Optional purchase:

• 1 Length of exhaust tubing (3″ I.D. x 10)

Lifting and Handling:

The furnace weighs 302 lbs (137 kg); do not attempt to lift by hand. Use a suitable lifting device to move the furnace into place. Employ established safe lifting and moving practices and consult trained professionals.

Site Selection:

• Place the furnace on a sturdy, level surface about 26-28 inches high, capable of supporting its weight.

• The surface must be level to permit the door to swing safely and remain open for loading/unloading.

• Allow at least 6 inches of space around the furnace for air flow and at least 40 inches above it to dissipate heat and prevent fire hazards.

• Locate the furnace so emissions can be directed through ducting to a fume hood or other appropriate ventilation system.

• An exhaust length of not more than 10 feet is recommended, if possible.

• The adjustable leveling feet should be used to level the furnace so the door will remain open.

• CAUTION: Ambient temperature must not exceed 40°C (104°F). Do not install above or near flammable substances as the unit has hot surfaces.

WARNING: This furnace must be installed by a licensed electrician and/or qualified craftsperson in accordance with all applicable National and local Electrical codes and requirements. The installation must include an external 35Amp Branch Circuit Protection rated for the application, certified in accordance with IEC 60947-2.

CAUTION: For supply connections, use 10 AWG or larger copper conductors only, suitable for at least 90°C. Failure to observe this could result in damage to the furnace and/or work area.

Electrical Specifications:

Volts	Model	Amps	Watts	Hertz
208	F85938	28	5757	50/60

Before connecting, ensure the front power switch and rear circuit breaker are in the OFF position. The power supply entry is at the right rear of the lower case. A terminal block is behind an access plate. Remove the six screws, connect the line and ground wires to the terminal block as depicted (L1 = Line, L2 = Neutral/Line, GND = Ground), and connect directly through a conduit system conforming to local electrical codes. The unit is supplied with a 7/8″ hole for 1/2″ conduit; utilize strain reliefs as needed.

WARNING: Failure to connect the exhaust port to an appropriate exhaust system will result in smoke and gases entering the work area.

CAUTION: Do not connect tubing less than 3″ in diameter or otherwise restrict exhaust flow. Do not connect the tubing directly to an external fan or otherwise increase exhaust flow velocity, as this may damage the furnace or reduce its efficiency.

1. Select a location to minimize exhaust length. A length of not more than 10 feet is recommended.

2. Use flexible 3″ I.D. seamless steel tubing or electrogalvanized steel tubing. Seal connections at the blower exit with clear silicon caulk/sealant, used sparingly for easy detachment. Do not use galvanized tin dryer pipe or double-wall galvanized tin as seams will leak fumes.

3. Minimize 90° bends in the system, as they restrict air flow and can accumulate particulates.

4. Terminate the exhaust in open air or to a larger exhaust duct. Open air termination is most efficient. Duct termination should not be near fresh air intakes, and the cap must not restrict air flow. If exhausting into a larger duct, an airtight connection is required, and the larger duct must not create positive air pressure. Perform the “lift test” to ensure a -3.2 to -8.2 gram lift. Increasing velocity above this lift may blow fines from the basket, causing exaggerated results.

5. If using a fume hood, turn on its blowers and conduct the “lift test” to ensure the -3.5 to -8.2 gram lift is maintained. Perform this test with room doors open and closed to ensure proper makeup air.

WARNING: Ensure the furnace is not connected to the power supply before installing or removing the balance.

CAUTION: Do not allow the ceramic support tubes to contact the sides of the tube ports, as this will cause an unstable and inaccurate balance readout.

1. Ensure the furnace is disconnected from power and the main circuit breaker is OFF. Remove the four screws on top of the front control panel. Move the furnace forward about 2 inches beyond the counter edge or raise the feet by 1/4 inch to allow the hinged panel to open without obstruction.

2. Carefully pull the control panel forward and downward to open the lower case. Do not let the panel fall completely open to avoid straining the cables.

3. Inside, locate the suspended balance support plate. Vacuum the plate if dusty.

4. Mount the support plate and catch pan onto the balance. The four pins on the catch pan will retain the ceramic support tubes.

5. Place the Setra balance on the support table with the gray ribbon cable protruding from the left. Plug this cable into the connector marked P2 on the front panel display board. Ensure the red and white power jack cable is plugged into P6 and the 9-pin ribbon cable is connected to P3 on the same board.

6. Position the balance so the pins on the platform support plate are directly beneath the four tube ports in the furnace chamber floor.

7. Open the furnace door. Insert the four ceramic support tubes through the tube ports, seating them on the appropriate pins on the balance plate. Adjust the balance position until the tubes are centered in their ports without touching the sides.

8. Place the 10″ x 11″ gray silicon carbide hearth tray on the four support tubes, with the 11″ dimension from front to back. Position the front of the tray about one inch back from the lip of the bottom element plate and center it equally from side to side.

9. Close the lower case by returning the control panel to its original position and securing it with the four screws.

10. Switch the main circuit breaker on. Close the furnace door and switch the power “on”. The balance display should read 0.0 grams after about 20 seconds. If it’s unstable or reads anything else, turn the power “off” and reposition the balance, checking for rubbing support tubes.

Note: The balance control buttons (ENTER, ON/OFF) are accessed through pin holes on the right front control panel below the balance indicator.

To Set the Time (24-hour format):

1. Switch the green power switch down to “OFF”.

2. While holding the “4” key, switch the green power switch up to “ON”. The red display should show [BAL CAL].

3. Press and hold the balance “ON/OFF” key.

4. Press the balance “ENTER” key, then release both keys. “71nE” will be displayed. Press the balance “ENTER” key again. The two hour digits will be blinking.

5. Press the balance “ON/OFF” key until the correct hour is displayed.

6. Press the balance “ENTER” key; the two minute digits will start blinking.

7. Press the balance “ON/OFF” key until the correct minute is displayed.

8. Press the balance “ENTER” key. The balance will return to the normal weight display.

To Set the Date (US type, 2-digit year format):

1. Switch the green power switch down to “OFF”.

2. While holding the “4” key, switch the green power switch up to “ON”. The display will show [BAL CAL].

3. Press and hold the balance “ON/OFF” key.

4. Press the balance “ENTER” key, then release both. [71nE] will be displayed. Press the balance “ON/OFF” key; [dA7E] will be displayed.

5. Press the balance “ENTER” key; [US] (United States) or [Eur0] (European) date type will be displayed.

6. Press the balance “ON/OFF” key to select the desired type.

7. Press the balance “ENTER” key; [2d Yr] (Two digit) or [4d Yr] (Four digit) will be displayed.

8. Press the balance “ON/OFF” key to select the desired format.

9. Press the balance “ENTER” key; [dAY XX] (Day) will be displayed.

10. Press the balance “ON/OFF” key to set the correct day.

11. Press the balance “ENTER” key; [nn0 XX] (Month) will be displayed.

12. Press the balance “ON/OFF” key to set the correct month.

13. Press the balance “ENTER” key; [Yr XX] (Year) will be displayed.

14. Press the balance “ON/OFF” key to set the correct year.

15. Press the balance “ENTER” key. The balance will return to the normal weight display.

Note: The furnace door should remain open during balance calibration. The balance must display “0.0” before starting calibration.

1. Switch the green power switch down to “OFF”.

2. After the furnace has cooled to room temperature, open the furnace door.

3. Remove and clean any debris from the ceramic load plate, balance load plate, and ceramic support posts. Replace posts and plates.

4. While holding the “4” key, switch the green power switch up to “ON”. The red display should indicate [BAL CAL].

5. Press and hold the balance “ON/OFF” key.

6. Press the balance “ENTER” key, then release both keys. [71nE] will be displayed. Press the balance “ON/OFF” key twice; [CAL] will be displayed.

7. Press the balance “ENTER” key. [LOAd 8000] will be blinking on the display.

8. Place an 8000 gram (NIST traceable) weight on the ceramic load plate in the furnace.

9. Press the balance “ENTER” key. The balance will display [ACAL], then return to the normal weight display.

CAUTION: Perform the “lift test” only when the furnace is at room temperature.

This test indirectly monitors the efficiency of the blower and/or exhaust system.

1. Fully assemble the tester with the exhaust system attached, hearth tray mounted on the four ceramic support tubes, and at room temperature with no load.

2. Depress the power switch to the “on” position. Depress the “0” key to tare the balance display.

3. Push the program “start” button. The blower will turn “on”. Observe the balance display reading, which should be between -3.2 to -8.2 grams. If the initial test is out of spec or borderline on the -3.5 grams low side, detach the exhaust system and repeat the test to determine if the exhaust system is restricting air exchange.

The printer automatically prints a record of the furnace’s operation. When you press “Start/Stop”, it prints the date, time, spaces for sample ID/mix type/tester name, and the filter and chamber setpoints. It then prints a column header “T:TEMP:WT.LOSS:%LOSS” and prints data for these four measurements every minute during the test.

At the end of the test, it prints the calibrated asphalt content, Bitumen Ratio, calibration factor, temperature compensation factor, total uncorrected percentage of sample weight lost, total weight lost in grams, initial sample weight, and total elapsed time.

Running out of paper: If the printer runs out of paper, the test will not stop. Results are stored. Install a new roll, and printing will resume. If the test finishes before you install a new roll, press “Start/Stop” to conclude. “Prn” will display in the Elapsed Time window. Load a new roll and press “Enter” to print the results of the last test. You can press “Enter” multiple times for additional copies.

Printer Access: The printer door is opened by depressing the button on the left side of the door.

Paper Advance Button: A button on the upper left corner of the printer advances the paper when the printer is inactive.

1. Switch the furnace power on. Press the Paper Advance button to feed out any remaining paper.

2. Open the printer cover and remove the retaining disk and empty paper roll tube.

3. Cut the lead end of the replacement paper.

4. Remove at least six inches from the lead end of the paper to remove any adhesive.

5. Insert the new paper roll on the paper roll shaft. Replace the retaining disk with the raised face toward the paper roll, ensuring the clips lock into the disk.

6. Feed the cut end of the paper into the slot at the bottom of the printer. Push the feed button on the front of the printer until about 1″ of paper comes out the front.

7. Close the cover.

NOTE: The heat-sensitive paper will print on only one side and must be installed properly to function.

The thermal paper tape is sensitive to heat and light and will darken if exposed for extended periods. To ensure long-term legibility of your records, use one of the following methods:

1. Photocopy each day’s tapes and file the photocopy.

2. Store the original tapes in an opaque folder, file, or envelope.

Avoid the following situations which hasten the degradation of the thermal paper:

• Exposure to heat or hot surfaces will darken the paper and obliterate readings.

• Ultraviolet light, including low levels from common fluorescent lights, will darken the paper over time.

• Common cellophane tape interacts with the thermal paper and will darken it to illegibility. Use care if taping original records into a notebook.

WARNING: Do not open the door while a program is in process. Flame and noxious fumes may be released. Always allow the test program to reach its endpoint before opening the door.

WARNING: Do not load cutback asphalt samples containing explosive volatiles. Explosive ignition can occur.

CAUTION: Do not exceed the 5000 gram capacity. “HHHHHH” will be displayed on the balance if the weight limit is exceeded.

1. Weigh your sample on an external balance, accurate to ±1 gram.

2. Enter the sample weight into the controller. Press the “Weight” button, enter the four-digit weight in whole grams, and press “Enter”.

3. Check and adjust the temperature setpoint and correction factor as needed.

4. Load the basket assembly into the furnace chamber, setting it gently on the hearth tray. Ensure proper placement from front to back and check for clearance on each side. Keep objects away from the thermocouple.

5. Use insulated gloves, a fire retardant apron, and safety glasses or a face shield when loading and unloading. Close the door, ensuring the basket tray does not touch the door insulation. The furnace will not operate with the door open.

6. Press the “Start/Stop” button. The automatic locking mechanism will lock the door. After 5-15 minutes, the asphalt will ignite, causing a sudden increase in the chamber temperature. As the temperature declines and the sample weight stabilizes, an audible alarm and stable light will indicate test completion.

7. Press the “Start/Stop” button to unlock the door. Use appropriate safety apparel and tools to unload the hot furnace.

This feature allows you to set an automatic preheat time for the furnace. It is recommended to set the time for at least 2-2.5 hours before you want to begin work.

1. Press the timer button on the keypad. The heating elements will shut down. The wake-up time will be displayed in the “Elapsed Time” display, and the wake-up date will be in the “Percent Loss” display.

2. Enter the “wake-up” date by inputting the month and then the day (e.g., May 16th is entered as 516). Press ENTER.

3. Enter the “wake-up” time using European or Military time format (e.g., 5:00 a.m. is 500; 5:00 p.m. is 1700). Press ENTER.

Bypassing the Date: If you don’t want to enter a date, press ENTER after pressing the timer button. This converts the timer to a 24-hour timer that ignores the date. The date needs to be set at 0.00 for this to happen.

Interrupting the Timer: To interrupt the Timer mode, press “Start/Stop”. The heating elements will re-energize. To return to Timer mode, press the Timer button again.

Problem	Possible Cause	Diagnostic	Remedy
AC results too high	Sample not dried to a constant weight	Review standard method HMA sample preparation	Re-dry
	Calibration factor for the aggregate not entered or is incorrect	Review Calibration Factor Display	Correct or re-enter
	Calibration factor is incorrect	Review Calibration Factor Display	Correct calibration factor
	Entered sample weight incorrectly	Review Sample Weight Display	Correct weight entry
AC results too low	Chamber temperature too high, causing aggregate to deteriorate, causing excessive weight loss	Review standard method calibrating factor procedure for sample preparation	Rerun calibration factor test per standard method
	Insufficient air exchange in chamber resulting in incomplete combustion of sample	Perform “lift test” to ensure a -3.2 to -8.2 gram lift	Oil and clean blower assembly. Replace blower. Clean exhaust system. Repeat lift test.
	Sample weight and/or calibration factor readout entered incorrectly	Check test tape	Correct Calibration Factor
	Basket assembly lodged against chamber or door resulting in low weight value		Correct position of basket assembly

If power to the THERMO SCIENTIFIC F85938 is interrupted during an ignition test and then restored, the furnace will continue the test. It will print “{Results Invalid}”, “Test Interrupted”, and the time of the interruption on the ticket. The elapsed time will restart at 1 and continue. The software will continue to monitor the weight loss and recognize the endpoint to end the test. This feature prevents smoke from entering the lab, as the blower will restart to maintain airflow. It also prevents the user from prematurely opening the door. This feature also applies to the programmable timer; if power is lost and restored before the “wake-up” time, the unit will still wake up at the correct programmed time.

Furnace error codes are displayed in the red LED windows on the control panel. All errors (unless noted) will stop the test procedure.

Error Code	Description and Remedy
E001	Chamber thermocouple circuit is open. The tip may be cracked. Replace thermocouple. Check for loose connections.
E002	Filter thermocouple open. Follow the same procedure as for E001.
E003	Chamber temperature limit of 675°C is exceeded. Caused by: 1. Deteriorated thermocouple (replace if resistance is not <= 1 ohm). 2. HMA sample size/oil BTU content is too high (split sample or reduce size).
E004	Filter temperature limit of 975°C is exceeded (see E003 explanation).
E005	Door interlock not functioning. Caused by: 1. Plunger rod off center, linkage jamming, or plunger location shifted (adjust as needed). 2. Bend or ding in the outer case where door lock linkage is attached (straighten case and adjust). 3. Microswitch failure.
E007	Analog to Digital Converter is not functioning properly. May be a component failure or faulty cable connection.
E008	The DTR signal from the balance indicates it’s not ready or not connected.
E009	Setpoint is out of range. This is a temporary error when setting a function. The furnace will beep for 3 seconds and revert to the previous value.
E010	Chamber thermocouple leads reversed. Polarity must be consistent (red is -, yellow is +).
E011	Filter thermocouple leads reversed. Polarity must be consistent (red is -, yellow is +).
E012	Balance not communicating; weight, time and date not received. May be caused by incorrect balance configuration. Follow the “Balance Default Settings” procedure.

These codes are displayed in the green Balance indicator window.

Error Code	Description and Remedy
HHHHHH	Exceeds maximum specified load. Remedy: Reduce loads to specified range.
LLLLLL	Load does not meet minimum specified load requirements. Remedy: Increase load to specified range.
NOCAL	Unable to do span calibration (load not within 1% of cal weight, or weight unstable).
UnABLE	Unable to process command (usually due to being in improper mode).
ProtEc	Calibration protect switch not in the PROTECT position during operation.
REPlug	System not calibrated.
OFLO	Internal arithmetic overflow.
S Err	Processor stack overflow.
In Err	Memory indexing error.

Hidden Key Routines are accessed by depressing a specific key while simultaneously switching the Power Switch to “ON”.

0 Key-Diagnostics: Accesses diagnostic procedure for factory testing. Printout is typically filed with the manual. Exit by turning power OFF, then ON.

1 Key-Printout Paper Saver: Toggles intermediate printing “ON” or “OFF”. The new mode is displayed for three seconds. Exit is automatic.

2 Key-Default: Resets variables to factory values. DEF is displayed for three seconds. Exit is automatic.

3 Key-Chamber Calibration: Enters chamber calibration mode. Displays CHBR CAL. Allows you to enter the actual temperature from a digital pyrometer to set a new offset value. Exit by turning power OFF, then ON.

4 Key-Balance Menus: Provides entry to balance menus to change time/date, review/adjust balance inputs, and calibrate. Displays BAL CAL. Exit by turning power OFF, then ON.

5 Key-Filter Temperature Adjustments: Allows adjustment of the filter setpoint (range 0-900°C). Use keypad to enter new value and press ENTER. Exit by turning power OFF, then ON.

6 Key-Disables Error Codes: Inactivates error codes for diagnostic purposes. ERR OFF is displayed. Exit by turning power OFF, then ON to reactivate error codes.

7 Key-Displays Actual Temperatures: Displays actual chamber and filter temperatures to assess need for replacement or recalibration. Exit by turning power OFF, then ON.

8 Key-Serial Port Output Adjustment: Toggles serial port output between continuous (SPC) and program-only (SPn). Exit is automatic.

9 Key-Disables Beep: Toggles the end-of-test beeper “ON” or “OFF”. The key press beep is not disabled. Exit is automatic.

Weight Key-Prints Balance Variables: Prints a list of scale variables. Exit is automatic.

Enter Key-Prints User Variables: Prints a list of user variables. Exit is automatic.

Calibration Factor Key-Adjust Test Stability Threshold: Allows adjustment of the test stability threshold (0.01-0.5%). Enter new value via keypad and press ENTRY. Exit by turning power OFF, then ON.

Temp Key-Toggles Auto/Manual Program Switching: Toggles between Auto Program Switching to Idle (AU “ON”) and Manual Program Switching to Idle (AU “OFF”) at endpoint. Exit is automatic.

Timer Key-Disables Inactivity Check: Toggles the Inactivity Check feature “ON” or “OFF”. Exit is automatic.

Element Plate Care:

It is normal for refractory plates to develop hairline cracks. This does not require replacement if mechanical strength is not compromised. Periodically fire the chamber at 650°C for two hours in idle mode to clean the element plates. Vacuum the chamber floor as needed.

Blower Maintenance:

Every six months, or if the “lift test” indicates a decline in efficiency, the blower requires cleaning and oiling. This requires detaching the exhaust duct and removing the top cover and fume hood. The motor is fastened to the rear of the fume hood. Place one drop of Anderol High Temperature Lubricant into the small oil ports on the blower motor. A 2″ wide paint brush and a vacuum cleaner can be used to clean the assembly, baffle plates, ceramic vent tubes, and flame deflectors. Wearing glasses is recommended.

1. Disconnect the furnace from the power supply and ensure the main breaker is in the OFF position.

2. Remove the back terminal cover of the furnace, noting the placement of the T/C lead wires.

3. Remove the screws on the chamber thermocouple terminals and disconnect the wires.

4. Remove the clamp retaining the thermocouple.

5. Pull the thermocouple straight back.

6. Insert the new thermocouple into the furnace and connect the leads to the terminal block, matching the wire colors.

7. Secure connections with the screws from Step 3.

8. Replace the back terminal cover.

9. Reconnect the furnace to the power supply.

10. Test the operation of the furnace.

1. Disconnect the furnace from the power supply and ensure the main breaker is in the OFF position.

2. Remove the back terminal cover of the furnace, noting the connection of T/C lead wires.

3. Remove the screws on the filter thermocouple terminals and disconnect the wires.

4. Remove the clamp retaining the thermocouple.

5. Pull the thermocouple straight back.

6. Insert the new thermocouple into the case.

7. Replace the clamp securing the thermocouple.

8. Connect the leads to the terminal block, matching the wire colors with the incoming wires.

9. Replace the back terminal cover on the furnace.

10. Reconnect the furnace to the power supply.

11. Test the operation of the furnace.

To Replace a Door Switch:

1. Disconnect furnace from power supply and ensure the main breaker is OFF.

2. Remove the four top screws on the front dial plate.

3. Open the front dial plate and remove the shield covering the door switches.

4. Disconnect the wires from the door switch to be replaced, noting the connections.

5. Remove the two screws from the Microswitches.

6. Insert the new Microswitch and secure with the screws from Step 5.

7. Reconnect wires to the new door switch and replace the wire shield.

8. Close the front dial plate and install screws.

9. Reconnect to power supply.

10. Test the operation of the door switch.

To Realign Door Switch Bracket:

1. Disconnect furnace from power supply and ensure the main breaker is OFF.

2. Loosen the screws that retain the door switch bracket on the bottom left side of the door.

3. Move the bracket closer to the furnace to make the switch engage sooner, or further away to engage later. Lightly tighten screws to hold position for testing.

4. The switches should click when the door is approximately 1″ from being completely closed.

5. Tighten screws once the bracket is positioned correctly.

6. Reconnect to power supply.

7. To test, turn the power on, set the control to a high setting to prevent cycling, and listen for the mechanical relay to click when the door is about 1″ from being closed.

The Calibration Factor addresses the aggregate weight loss or gain that occurs during the ignition process. This change in weight is not related to asphalt content loss and is added to or subtracted from the final asphalt content. Standard methods specify the procedure for determining this factor, which is entered by the operator.

This factor compensates for the weight reduction of the loaded basket assembly when it is placed in the hot furnace chamber. The Temperature Compensation Factor is automatically calculated by the furnace software and must be used in the ignition process to achieve acceptable precision and accuracy as specified by standard methods. This factor is subtracted from the asphalt content.

The Test Endpoint is the point at which the HMA sample’s weight loss does not exceed the “Test Stability Threshold Setting” for three consecutive one-minute periods. Furnaces with Rev. H software will end the test, asterisk the endpoint reading on the printout, and switch from program mode to idle mode at the endpoint if the Auto Program Switching to Idle feature is employed.