NCAT FAQs

The NCAT furnace requires either a 208 for Model F85938 units or a 240 for model F85930 units (most common unit), single-phase VAC Supply. It will draw 28A of current.

You will need a “buck-boost” transformer; this can be purchased at HMA Lab Supply; PN NC-2905

The NCAT does not come with power plug attached, this is left for the local electrician to work with local codes and requirements.

• The exhaust tube can reach up to 270C (518F). We recommend a flexible stainless-steel tubing up to 10ft in length.
• Minimize bends in the tubing for best effect. You should have no more than one 90-degree angle per 10 feet of exhaust
• Exhausting the tube into a hood with a positive draw may affect the stability of the scale inside the NCAT furnace. Check the lift measurements by performing a Lift Test in to ensure proper operation. Refer to manual to perform a Lift Test.

• After 10ft, a booster fan may be required. Consult an HVAC technician
• The fan mounted on the NCAT furnace is rated for 65CFM; any booster fan will need to be rated lower than this rating to avoid negative air pressure

The furnace dimensions are 21.75x36.75x25.75. We recommend adding 12in on the left and right sides of the furnace and locating it at least 6in from the wall behind the unit.

• Check the SN of the furnace; this can usually be found on either the back of the furnace, or the right side next to the door plunger.  To determine the type of furnace, you need the first three or four digits of the SN.  If they are ‘859’ or ‘945’, then you have what is called an 859/945 furnace.  If it is ‘1087’, ‘1275’, or any other combination of numbers, then it is a 1087/1275 furnace for the use of the furnace?
• These furnaces typically run at 482/538°C (900/1000°F), so there is a significant burn/fire hazard.  To that end, these are the safety equipment you should have on hand when using this oven:
• Gloves (with arm shield—AP-5130, without—AP-5125)
• Face shield—SA-1100
• Extended forks to handle the baskets—NC-1255
• Insulated Plate to set the basket—NC-1155
• Cover basket to prevent accidental brushing of the basket as it is cooling down—NC-1150
• Baskets to store the samples during the ignition process as well as cooling down—NC-1200
• If you would like to get all these items at once, instead of ordering them piecemeal, there is an NCAT Furnace Accessory Kit—NC-1002

Sample sizes are determined by mix, state requirements, and various other external factors. However, most samples typically run between 1200 and 2000 grams. The larger the sample, the more time it will take to burn.

While there are variations based on sample size, asphalt content, and other factors, most burns typically take from 30-45 minutes.

The test will be complete when the scale records the same value for three consecutive minutes. Once the test is complete, the unit will beep, print out the remainder of the ticket with the results, the door will unlock, and the display will read ‘DONE’ in the ‘elapsed time’ window

The NCAT furnace has two measurements that may need to be calibrated. The scale should be calibrated annually. Also, some states like California and Michigan require temperature verification. Check your state specification for furnace verification requirements.

We recommend cleaning the furnace at least once every 6 months

• A lift test is performed when you turn the furnace on for the first time in the morning.  It should be at room temperature.  Once the scale countdown is finished, and the chamber is empty, hit start.  The green display should pull down to somewhere between -3 and -8
• We recommend doing a lift test at least monthly.  If possible, perform the test weekly

• Check the most recent scale calibration.  If it has been longer than a year, get it recalibrated
• Check the most recent lift test; if it is lower than -3 (say, -2.5), clean the top of the unit to see if the situation improves
• Check to see if the ceramic tubes are touching the sides.  When they rub, they cause the weight to appear to be jumping around and/or going backwards
• Verify the time and date on the scale.  If you see ‘--:--’ it means that the information has been lost and needs to be reset.
• If possible, verify that the scale is reading correctly.  If you have a known weight, this can be used.  Otherwise, compare against an external scale

• Check the most recent lift test; if it is lower than -3 (say, -2.5), clean the top of the unit to see if the situation improves
• Check to see if the ceramic tubes are touching the sides.  When they rub, they cause the weight to appear to be jumping around and/or going backwards
• Verify the filter temperature.  Do this only after the unit has been heating up for more than 10 minutes.  This can be done by turning the unit off, holding down the ‘7’ key, and turn the unit on. Hold down the ‘7’ until the red display lights up and check the numbers in the ‘chamber temp’ and the ‘percent loss’ windows.  ‘Percent loss’ should be the larger number.  If it is not, replace the filter element—there are two filter elements, based on series.  NC-1410 for the 1087/1275 series, and NC-1425 for the 859/945 series

See “Long Burn Times” above

This is a safety feature, often used alongside the startup timer. It only triggers if the furnace is idle for over 4 hours, and it shuts the heating elements off. To reactivate it, just hit ‘enter’ on the keypad and the furnace will begin operating as normal

• If the temperature is below 50F (10C), take a match/cigarette lighter, and apply the flame directly to the chamber thermocouple for 15-30 seconds.  Once the red display starts to change, the furnace should begin heating when you close the door
• Occasionally, when the furnace has been idle for several days, the red display is a little slow to respond.  Close the door for 30 seconds, then feel the left, right, top, and bottom walls of the chamber.  They should begin to feel warm to the touch.
• Check the door interlock.  There is a tab on the lower side of the door, near the hinges.  It should go into a slot on the furnace itself.  Verify that the tab is going in correctly; sometimes the tab will catch and get bent.

• Check the heating elements.  They are the left, right, top, and bottom walls of the chamber.  If or more of them is cool, while the others are warm, they will need to be replaced.  As there are multiple variations, you will want to check the website and/or call HMA Lab Supply to ensure you order the correct part.  Please verify your model and SN as outlined in the “General Information” section prior to ordering
• If the left and the right heating elements are not heating, you will want to ensure your furnace is not in the low-power configuration.  This is an older configuration that was designed for 20A use and disables the left and right elements.  To check the configuration, unplug the furnace from AC power, open the back panel of the furnace and check the lower left-hand corner.  There should be a wire joining the two connectors there.  If it is either not present or connected to itself, then the furnace is in the low-power configuration.

• Check the blower fan is running and relatively quiet.  If the fan needs to be replaced, PN NC-1500 (1087/1275) or NC-1520 (859/945)
• Clean the upper section of the NCAT furnace as described in the maintenance section
• Verify the door is closing correctly.  See “Door Loose” section
• Check the filter temperature as described in the “Long Burns” section
• Verify there are no obstructions in the exhaust tube

If the door is loose, you will need to realign the door and tighten the hinges. This can be accomplished by closing the door, pulling out on the hinges until the door sits flat against the furnace, and tightening the hinges down

Replace the solid-state relay—Part Number NC-2510

• Unplug the printer and plug it back in
• Replace the printer.  The replacement part number is NC-1950.  Note: if the printer you are replacing is white, the new printer dimensions will be different.  You can either cut the hole to fit with a Dremel tool, or order a replacement front panel (NC-1312)

Replace the main logic board—Part Number NC-2300

Replace the keypad. If the printer is white, NC-1315. If black printer, NC-1312.

• Most likely, the solenoid will need to be replaced.  NC-2610
• Check the mechanical linkage.  In the center of the linkage is a nut that it pivots around.  Loosen the nut about 1/8 turn
• In the short-term, you can actuate the plunger with a small, flat-tip screwdriver

• Try cleaning the fan out as described in the “Maintenance Section”
• If that fails to alleviate the problem, you will want to replace the fan.  PN NC-1500 (1087/1275 series), NC-1520 (859/945)