Frequently Asked Questions Page


Question: How do I increase the maximum heat setting of the seal wire with a SEAL-A-TRON ™ L-BAR SEALER.
Answer: Our special TRU-TEMP ™ Logic board allows you to simply turn a knob to increase or decrease the temperature.

Question: Why is it important to have super strong magnets on L-Bar Sealers.
Answer: Our extra strong magnets produce lots of seal pressure, which in turn gives you a stronger seal.

Question: Why do we have to buy the special SEAL-A-TRON ™ seal wires?
Answer: Our seal wires are specially made to meet the high levels of tolerance required for long wire life. Our seal wires are able to assure the even voltage flow throughout the entire seal area helping to create the strongest seals in the industry. Each wire has a 2” heat sink on the end with a hi-temp terminal which helps eliminate the very common occurrence of wire breakage. We have designed not just a wire but a complete seal wire delivery system that will improve performance and last longer than conventional wires if installed correctly.

Question: Is there any way to run PVC or Polyethylene film on a SEAL-A-TRON ™ L- Bar Sealer?
Answer: Yes. In order to eliminate the build up of residue to the seal wires, they must be covered with 1/2” width, 3mil Teflon tape. Run the tape along the entire length of the seal wire on both side and front. Adhere the tape to the seal bar backing (either a transite strip or beads depending on which model of sealer). Make sure the seal wires are covered completely with the Teflon tape. This will assure consistent performance. It may be necessary to adjust the dwell setting and the temperature setting to achieve strong seals. Do this by setting both control knobs to -0-, then increase the temperature and dwell until clean and strong seals are consistently being made.

Question: When should I replace the Teflon tape on the L-Bar Sealer’s seal bed?
Answer: At the first sign of burn through. This is very important because failure to replace the Teflon tape could result in the destruction of the seal pad located under the tape. This open cell foam padding is expensive to replace and will definitely result in poor seal performance. Also, it is quite common for operators to increase the wire temperature at the first sign of poor seal quality. In most cases, however, they are compensating for lack of seal pressure created by the gap left by the burned in crevice in the tape. Replace the tape right away to keep this from happening. (Note: 3/4”, 10mil Teflon tape is suggested.)

Question: How do I adjust the tracking on the power discharge conveyor belt?
Answer: Our power discharge conveyor is designed to track consistently, but over the life of the sealer it may be necessary to adjust the belt. There is a tracking adjustment mechanism located at the discharge end of the conveyor. First loosen the 2 ¼-20 bolts that lock in the adjustment bracket with a 7/16 wrench. Then, use a wrench to turn the adjustment bolt 1/8 turn at a time. Cycle the sealer watching for the correct belt alignment. The tracking mechanism requires very slight turns to achieve the desired results. There Is a jumper on the main PCB marked “CONVEYOR SET-UP. Moving this jumper from the “NORMAL or A” position to the “SETUP RUN or B” position will make the conveyor belt run continuously and make tracking much easier. When tracking is satisfactory, return the jumper back to the “NORMAL or A” position. Consult your local SEAL-A-TRON ™ service tech for more details. The belt should always hug the left side of the conveyor frame

Question: Why does SEAL-A-TRON ™ fuse the seal wires?
Answer: Our seal wires are protected by 15amp slo blow fuses. This fuse is there to protect the seal wire from shorting out. The fuse will blow before the seal wire brakes, and it is faster to replace a fuse, than a seal wire. If a fuse should burn out it is important that it is replaced with the same type of fuse.

Question: Is there any way to clean off the film build-up on the seal wires?
Answer: Yes. Our sealers have a burn-off switch. By activating this “PULSE BY-PASS SWITCH the seal wire will be heated with the SEAL-HEAD in the open position, so that any residue built up on them, will burn off. It may be necessary to also scrub the wires with a brass bristle brush immediately after this cycle. (This is not a hotter cycle; the wire will get only as hot as the setting on the control knob) The temperature of the wire is the same as a normal operating cycle. Therefore, it is helpful to increase the wire temperature.
CAUTION: Do not forget to return the wire temperature to the normal operating setting.

Question: Should the seal wires be touching at the “cross-over” point?
Answer: No. There should be a 1/32” gap between the front and side seal wire. Radiant heat from the wires will achieve the proper corner seal required. If the wires are too close, arcing can occur causing the wire to fatigue and break.

Question: What can I do to fully protect my SEAL-A-TRON ™ equipment from power surges?
Answer: The electronics that run the sealers functions are Metal Oxide Varistor (mov) protected and should not be affected by any electrical spikes. However, since the sealers are 120 volts and can be plugged into any outlet, a surge protector is recommended to provide extra insurance against damage.

Question: Can SEAL-A-TRON ™ PC boards be repaired?
Answer: Yes. Our P.C. boards are backed by a 1-year warranty against defects. After that period, if any repair should be required, your local authorized SEAL-A-TRON ™ technician can trouble-shoot any problem and make the necessary repairs. If the P.C. board is defective and needs to be replaced, it is possible to send that board to SEAL-A-TRON ™ for repairs. In most cases, our P.C. boards can be restored to perfect working condition for a nominal repair fee.


Question: With a live-roller conveyor system, when do I lubricate the chain?
Answer: Chains should be lubricated every 80 hours of operation.

Question: What is the best method for replacing the worn silicone coating on my live rollers?
Answer: The roller has to be removed from the shrink tunnel. Remove old silicone by cutting it off the roller. Use a fine steel wool pad to clean the rollers. Insert talcum or baby powder into the pre-cut silicone tube. Push the tube onto the roller as far as it will go. Take an air blow gun with a pressure regulator attached to it, (pressure should not exceed 20 lbs.) insert and inflate the blow gun into the other end of the silicone while taking your other hand and pushing it completely over the roller. (A foot pedal switch makes this a lot easier) **WARNING : If too much pressure is used, the silicone tube may be destroyed**

Question: What is the best method of replacing the TFE Teflon covering on my live roller?
Answer: Pre-cut the TFE Teflon tubing and place tubes into a 350 degree preheated shrink tunnel for 10 minutes. Use leather gloves when taking the covers out of the tunnel. They have now expanded substantially, and will slip over the live roller with ease. The Teflon tubes will tighten on the rollers as they cool.

Question: How do I clean out any film that may have accumulated in the tunnel chamber?
Answer: Remove the film curtain for easier access while the tunnel is still warm. Use a putty knife to remove any film residue accumulation within the tunnel.

Question: How often should we remove the dust out of the control panel?
Answer: The control panel should be blown out and vacuumed at least once a year. If the operating environment is excessively dusty, a six month cleaning may be necessary.

Question: Can I run polyethylene on a live roller conveyor?
Answer: No. A dead roller track should be installed. However, a GFN glass filled nylon belt will work well with polyethylene. To keep the dead rollers and the glass filled nylon belt from overheating, a cooling fan should be installed underneath the tunnel.

Question: What is an EMI/RFI line filter?
Answer: EMI/RFI stands for Electro - Magnetic Interference and Radio Frequency Interference. An EMI/RFI line filter must be installed, if the interference level in the working area has reached its limit. The line filter will reduce excessive electronic noise that will interfere with delicate other electronic equipment.

Question: Why is there a cool down cycle SEAL-A-TRON ™ shrink tunnels?
Answer: The cool down cycle will cool the interior of the shrink tunnel with the blower motor and conveyor motor running, but heat disconnected. This will cool the interior and live rollers, which extends the overall life of the shrink tunnel.

Question: What is the first step in trouble shooting this shrink tunnel when it is not running?
Answer: Check the power source at the plug or the main switch breaker in the shrink tunnel.

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SEAL-A-TRON ™ offers a 1-Year Warranty on all Equipment!

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SEAL-A-TRON ™ Corporation


3815 S.E. Naef Rd. * Portland, OR 97267
Phone (503) 652-5200 * Fax (503) 905-1331

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