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Troubleshooting Tips and Part # Information

Doboy Hospital Sealer

Following are recommended tips for troubleshooting Doboy Hospital Sealer problems.  You will also find a list of part numbers and descriptions for commonly used parts.

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Preventative Maintenance & Proper Use Tips*

Area of Machine

Advice / Technique

Changing Sealing Bands

(Applies to Hospital Sealer)

When the Stainless Steel Sealing Bands get kinked, bent, brittle, or broken, they will need to be replaced.

To change the bands on a Hospital Sealer, unplug the machine, open the front cover / guard, and remove the bottom guards.  Press the infeed-end (idler) band wheels (pulleys) in against their springs to take tension off one of the the sealing bands.  Slip the worn sealing band off of the Idler pulley, then remove it from the drive pulley.  Repeat the process for the other sealing band.

Reverse the process to install new sealing bands - install one band at a time - place the new band over the drive-end pulley (the pulley at the motor end of the machine).  Then, press on the Idler Pulley (against the tension spring) and slip the new band onto the Idler Pulley.

Repeat the process for the second band.

We will gladly try to talk you through proper set-up of your machine - Call us!

Interior Cleaning

(Applies to Hospital Sealer)

Periodically, unplug the machine, hinge open the front guard, and wipe dust out of the machine's interior.  Use a cloth or paper towel dampened with a mild cleaning solution (e.g. Windex).

Sealing Band & Rubbing Block Inspection

(Applies to Hospital Sealer)

Periodically, inspect the Hospital Sealer's Stainless Steel sealing bands for kinks, bends, or signs of cracking / breaking.  If any of these conditions exist, you should replace the bands.

As the machine is used, the surface of the round Rubbing Blocks will wear.  You will notice a flat spot on the surface of the round rubbing blocks where this wear has occurred.  When wear is noted, you can rotate the rubbing blocks to expose unworn sections of the rubbing blocks to the back of the sealing bands.

If you need to order replacement sealing bands or rubbing blocks, let us know and we will provide you with a quote.  Hospital Sealer Sealing Bands are sold in 10-pack cartons.

Heater Bar Gap Adjustment:

(Applies to Hospital Sealer)

For most medical sealing applications, the gap between the Hospital Sealer Heater Bars should be set to 0.018" (0.45mm).  This gap dimension may vary depending on the thickness of your bag / pouch material(s).  To check the gap setting, unplug the machine, remove the bottom guards and sealing bands.  CAREFULLY insert a feeler gauge between the heater bars (if you are not gentle, you may scratch off the Teflon coating or damage the surface of the heater bar.)

Generally speaking, all gap adjustments should be made using the set screw and cap screws on the front side of the machine.  First, loosen (counter clockwise) the set screw that contacts the rear, middle of the front heater bar.  Then, adjust the cap screws on either end of the heater bar.  Turning the screws clockwise makes the gap at that end of the heater bar wider.  Likewise, turning the screws counter-clockwise makes the gap at that end of the heater bar narrower.

When the gap is set where you want it, turn the center set screw in (clockwise) until it just touches the back of the heater bar (it should not be pushing too hard on the heater bar.)

We will gladly try to talk you through proper set-up of your machine - Call us!

Lubrication of Gears:

(Applies to Hospital Sealer)

The manufacturer recommends that you "1) Check Lubrication on a Monthly Basis or if sealer does not operate properly.  2) Brush a small amount of grease on the gear faces as necessary. and 3) Use Lubriko Hi Grease, or equivalent."  We caution you DO NOT over-lubricate!  Gears should have only a LIGHT COATING of grease on them.  While we offer the recommended Lubriko Hi Grease, any lithium-based grease suited to high-temperature use is useable.

General Sealer Set-up:

(Applies to Hospital Sealer)

Many Doboy machines we receive for service have been user-adjusted in a way that defeats the machine's ability to operate properly.  The sealer is designed to have a fixed side and a spring-loaded side - this applies to the heater bars and the belt/chain guides.  We will gladly try to talk you through proper set-up of your machine - Call us!

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Troubleshooting Tips & Tricks*

Problem Possible Cause & Solution

Does not seal or does not seal uniformly:

(Applies to Hospital Sealer)

1) Lack of Adequate / Uniform Heat:

1a) With the machine cold and the guards off, pre-heat the machine and check each heater bar as the machine heats to make sure both heater bars are getting hot, independently - it's possible that one of the heat elements (most likely the one on the side opposite the thermostat) is burned out.  If one bar does not get hot, there is either a loose connection or a bad heat element.

1b) For the same pouches you have been using, have you had to modify the thermostat setting recently?  If your thermostat is getting too old (typically 3-5 years old) it will sometimes prevent the elements from getting as hot as they originally did.

1c) If both elements are working, check the gap setting between the heater bars (See Bar Gap Adjustment Tip above.)  If the gap is too wide, it can prevent efficient heat transfer to the bag.

2) Lack of Adequate Seal Pressure - If both elements are working and your gap setting is appropriate, check your seal pressure.  Turn the set screw in front of the compression rollers clockwise to increase seal pressure and counter-clockwise to decrease seal pressure.

Over time, the rubber roller on the Hospital Sealer can become hardened and is unable to develop adequate / uniform pressure.  When this happens, you will need to replace the compression roller(s).

3) Seal Area Contamination - check bag for contamination (e.g. product residue, dust, grease, oil, etc.)

Cracked Plastic Compression Roller

(Applies to Hospital Sealer)

Cracked Plastic Compression Roller - Doboy Hospital Sealer

Cracked Plastic Compression Roller

Typical After 10-15 Years of Service

Hospital Sealer - New and Old Compression Rollers

New & Old Hospital Sealer Compression Rollers

BaggingGuys' Ship-In Service

(Click photos for larger Detail Photo)

Over time, heat from the sealing process and plain old age will cause degradation of your Hospital Sealer's compression rollers. 

The Compression Rollers rotate and press on the heated film to make a secure seal.  Their design, a hard plastic roller in the back and a spring-loaded, rubber roller on the front insure that uniform pressure is applied to the package and that a tight seal is made.

As the rollers wear out, their ability to make a uniform and reliable seal also deteriorates.  When they develop cracks, scratches,  or chips (on the rear, hard plastic roller), or flat spots and hardening (on the front-side, soft rubber roller) it's time to replace the rollers.

See the photos to the left to determine if your rollers are showing signs of cracks, hardening, or wear.

When the Compression Rollers have worn to the point that they need replacement, it's also usually time to replace the bearings that support the compression roller drive shafts - and not a bad idea to replace the Idler Pulley Bearings, as well.

It is not recommended that users attempt to remove and replace the Compression Rollers because replacing them properly is difficult and critical to proper sealer operation.  If you determine that your Hospital Sealer has worn, cracked, or damaged Compression Rollers, please contact BaggingGuys about our Ship-In Service for Doboy Portable Sealers!

PROBLEM: The Motor on my Doboy Hospital Sealer Will Not Start

or Will Not Run.

(Applies to Hospital Sealer)

1) Bad Motor Switch - Check your motor On/Off switch to make sure power is being supplied to the motor when the switch is in the Motor ON position.  If not, replace the switch (Part # 950644).

2) Motor Fan Interference - The cooling fan on the Hospital Sealer's motor is friction-fit onto the motor drive shaft.  If the fan blade is accidentally pushed too far up or too far down the shaft, it can interfere with the sealer guard or the motor itself, respectively. 

With the machine unplugged, carefully (and gently) push the fan blade up or down to insure that it doesn't interfere with the sealer's guarding or with the motor.  Note: when the motor switches on, the fan and shaft tend to rise a bit.  So, insure that you allow for this movement when positioning the fan blade.

3) Motor Burned Out - If your switch is operable and your fan blade is not interfering with anything, it's likely that your motor is burned out or the gear reducer is seized.  The gear reducer is an integrated part of the motor, so you will need to replace the whole assembly.

PROBLEM: Contact us with your problems.

(Applies to Hospital Sealer)

Contact us with your problems. We will post the solution here! Watch here for more solutions!

PROBLEM: I need service for my Doughboy Sealer or Doboy sealer.

(Applies to all tabletop Doboy / Doughboy Sealers)

If your Doughboy / Doboy sealer needs parts we can quote the parts.  However, unless you are an experienced mechanic who understands the operational principles of these sealers (e.g. why is there a fixed side and a spring-loaded side of the machine?) it's probably best that you do not attempt to service these machines yourself. 

BaggingGuys recommends you consider shipping your machine to us for repair evaluation and service.

Replacement and proper realignment of the power transmission and heating components on this sealer are critical and can be difficult if you do not have regular experience doing it.

* Machine troubleshooting & repairs should only be attempted by a qualified mechanic or electrician.  Power should always be disconnected prior to troubleshooting.

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Please see your factory instruction manual for additional troubleshooting tips.
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Common Replacement & Wear Parts (available at

Parts for Doboy Hospital Sealing Machine
Doboy Part # Description
016-00089 Sealing Bands for SIG Doboy & Bosch Doboy Hospital Sealer (sold in 10-packs)
950987 Rubbing Block
951002 Thermostat
232292 Compression Roller - Plastic, Smooth - Left-hand, Rear Side
231733 Compression Roller - Rubber, Smooth - Right-hand, Front Side
950241 Bearing (for Idler and Drive Pulleys)
953064 Bearing Block
697-01400 Knob for Thermostat
952535 Heat Element
950644 Rocker Switch
952190 Motor (with Integrated Gear Reducer) [110 V]
950006 Drive Gear
273164 Grease for Gears
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