ADDENDUM 1- Low Flow Selector KnobA low flow selector knob has been installed on some of the Bio-Med Devices Blenders (standardon units mounted on the Crossvent ventilators) in lieu of the auxiliary side port. This enables theuser to maintain accurate concentrations using the single primary output for both high and lowflows with a simple turn of the knob.A label attached to the side of the blender indicates how to position the knob for accurateconcentrations at settings less than or greater than the flow rate indicated. The knob must bepushed in prior to turning.ADDENDUM 2- NEO2 BLEND BlenderThe NEO2 BLEND is a low flow blender with two flowmeters mounted to it, one on each side. Anytime this blender is used below 3 lpm, an internal bleed is required to maintain the accuracy of theO2 concentration being delivered. Due to the unique design of the NEO2 BLEND, this bleed isautomatically activated when the flowmeter on the right is set to the “ON” position as describedbelow. To conserve gas, this bleed may be turned off when this flowmeter is not in use. Theflowmeter on the right side is for delivering flows below 3 lpm. The left flowmeter is generally usedfor flows above 3 lpm, but may be used below 3 lpm as explained below.The flow rate for these flowmeters should be set using the center of the ball.RIGHT SIDE FLOWMETERThe right side flowmeter and corresponding bleed is inactive when it is angled towards the front ofthe blender. To activate it and initiate the required bleed, push the flowmeter in towards the sideof the blender and then rotate it clockwise (towards the back) to its vertical position. The internalbleed will now be active and the flow rate may be set using the knob on the flowmeter. To returnthe flowmeter and bleed to its off (inactive) state, return it to its angled position by pushing it in androtating it counterclockwise (towards the front).LEFT SIDE FLOWMETERCAUTION: The flowmeter on the left side is stationary. Do not try to rotate it.This flowmeter is meant for flows above 3 lpm. It may, however, be used below 3 lpm with thefollowing consideration; when set below 3 lpm, turn on the required bleed by setting the right sideflowmeter to its vertical position following the procedure as described above. Even though theflowmeter on the right is not being used, having it in the vertical position activates the internalbleed thereby guaranteeing O2 accuracy while using the left side flowmeter at flows below 3 lpm.1

1. INTRODUCTION AND OPERATIONThe Bio-Med Air/Oxygen Blender is a precision proportioning device for mixing medical grade airand oxygen to any concentration from 21% to 100% oxygen and delivering it to a variety ofrespiratory care devices. The blender uses source air and oxygen at a pressure of 50 psiconnected to two D.I.S.S. fittings on the bottom of the blender. Each fitting has a built-in 30micron particulate filter. The gas source then passes through a duckbill check valve, whichprevents reverse gas flows from either source.WARNING: The factory installed Air and Oxygen gas supply fittings, whichcontain essential check valves and filters, must not be substituted with anyother parts not approved by Bio-Med Devices. Doing so may cause gas supplycontamination due to back-flow.The blender uses a two-stage balancing system with the gas entering into each stage to equalizethe operating pressure of the gas sources before entering the proportioning stage.The gases then flow into the proportioning stage where they are mixed to the percentage dialed inon the front panel knob. This stage has a double-ended valve with valve seats on either end.Each one of these valve seats controls the passage of the air or oxygen to the outlet of theblender.There are up to three gas outlets on the Bio-Med Devices blender depending on the model.Figure 1 indicates the various standard configurations.Blender PortsFrontBCAIRAO2Figure Flow Range - Port “A”Flow Range - Port “B”Flow Range - Port“C”3A, Knob @C6-50 lpm (No Bleed)0-50 lpm (6 lpm Bleed)N/AN/AKnob Set 6Knob Set 6A, C15-120 lpm (No Bleed)N/A2-108 lpm(10-12 lpm Bleed)A, Knob @C15-120 lpm (No Bleed)2-108 lpm (10-12 lpm Bleed)N/AN/AKnob Set 15Knob Set 15A15-120 lpm (No Bleed)N/AN/AB, CN/A3-30 lpm (No Bleed)0-30 lpm (3 lpm Bleed)A, B, C15-120 lpm (No Bleed)15-120 lpm (No Bleed)2-108 lpm (10-12 Bleed)Note 1. Mounted on Crossvent 2 ventilator.Note 2. Mounted on Crossvent 3 & 4 ventilatorsNote 3. Some special order blenders may not have a bleed in this port. For these blenders, the output range would be the sameas for those flows indicated with no bleed.NOTE: The NEO2 BLEND with two flowmeters conforms to the model #2003 configuration with flow limited by the flowmeters.Refer to Addendum 2 in the beginning of this manual.1.1 PRIMARY OUTLET2

Figure 2 illustrates the flow pattern when air and oxygen are provided to the inputs under normalconditions using the primary outlet for the exiting of blended gas. The gas sources enter the lowersection of the blender where they pass by a shuttle spool. This spool is used for the alarm andremains balanced in this instance, thus blocking passage of gas to the alarm. The gases continueinto the first stage of a two-stage balancing chamber. Here, the diaphragm reacts to anydifference in source pressures and helps equalize these pressures. From here, the gasescontinue into the second stage of the balancing chamber where again, a diaphragm adjusts toequalize any remaining difference in pressure. The gases then exit the balancing chamber andenter the proportioning valve. Here the two gases are metered to the proper proportions resultingin the concentration as set by the knob on the front of the blender. From the valve, the nowblended gas exits the blender through the primary outlet. Each outlet has a check valve thatprevents gas from passing through it unless a hose or other device is threaded onto it.Figure 23

1.2 AUXILIARY OUTLETFigure 3 illustrates the same conditions as Figure 2, but with the blended gas exiting the low flowauxiliary port. Use of this port induces a bleed to atmosphere which is necessary to maintainaccurate concentrations when using the blender at flows of less than 15 lpm (3 lpm in the LowFlow Blender, 6 lpm in the 0-50 LPM Blender).Figure 31.3 ALARM CONDITIONThe blender has an audible alarm built in to detect if either of the gas sources changes by morethan 20 psi (30 psi for units sold overseas) from the other. This will warn the user that they arerunning out of one of the gas sources or that there is a severe pressure drop in one source. Ifboth gas sources drop or increase together such that a 20 psi (30 psi for units sold overseas)difference cannot be detected, then no alarm will sound. If the blender is connected but not beingused and a 20 psi (30 psi for units sold overseas) difference in gas sources develops, the blenderwill not alarm.The blender alarm/bypass function will provide 90 LPM ( 30 LPM capability in the Low FlowBlender, 50 in the 0-50 LPM Blender) upon the loss of air or oxygen, if the remaining gas is at 504

psi. Fig. 4 illustrates the flow pattern when the air source is lost and only oxygen is provided to theinput using the primary outlet for the exiting of gas. Notice two major events occurred relative tothe previous figures. First, the alarm shuttle has shifted to the air side due to the absence ofpressure on this side. This now exposes the passage to the alarm and the bypass to the outlet.Second, the diaphragm in the first stage of the balancing chamber has shifted due to theimbalance of pressure and has closed the oxygen side.Figure 45

2. WARNINGS AND CAUTIONSWARNINGS:Only qualified, trained service technicians should attempt repairs and service when needed.The blender must not be exposed to extremely high temperatures, as in the case of steamautoclaving (which could reach 145 degrees F).The blender is designed to operate from a 50 psig source of air and oxygen.An oxygen analyzer should be used to verify the gas concentration and when making anyadjustments to the concentration.Be certain all components are properly installed prior to pressurizing the blender. Parts improperlyinstalled may be ejected.Bio-Med Devices cannot be held responsible for any failure to adhere to the recommendations setforth in this manual.Because this is a CE marked device, it must never be modified without prior expressed writtenconsent from Bio-Med Devices.The factory installed Air and Oxygen gas supply fittings, which contain essential check valves andfilters, must not be substituted with any other parts not approved by Bio-Med Devices. Doing somay cause gas supply contamination due to back-flow.CAUTIONS:Moisture or dirt can affect the operation of the blender; a clean dry gas source must be used at alltimes. The air must meet USP compressed air and ANSI Z86.1-1973 grade F and water vaporcontent cannot exceed a dew point of 5 degrees F. below the lowest ambient temperature to whichthe blender and accessories are exposed.A water trap assembly and filter must be used to avoid malfunction should water accidentally getinto the gas supply sources.Always apply pressure to the blender slowly.If the blender has a flowmeter on the left side, it is stationary. Do not try to rotate it.6

3. PREVENTIVE MAINTANENCEPeriodic preventive maintenance should be performed to insure continued proper operation ofthe blender. The frequency of preventative maintenance is determined by many factors,some of which are:Frequency & length of useQuality of the compressed gas source(s)Environmental conditionsRecommended Maintenance ScheduleIntervalRecommended ProceduresPrior to each usePerformance testEvery year between PM’sCalibration certificationEvery 2 yearsMajor overhaul, cleaning and calibrationRecommend return to factory for this serviceGas Inlet FilterThe filter element in the air and oxygen supply inlet fittings should be replaced during majoroverhauls or whenever they become contaminated.Preventive Maintenance Parts KitPart Number 2008 -All BMD BlendersIncluded in the kits are the following parts: Filters, O-rings, check valve ball, balancing chamberballs, duck bill check valves, bleed muffler and retainer, diaphragms, spring, label. This kit issubject to change without notice.4. TOOLSAdjustable Spanner5/32” Hex Wrench1/8” Hex Wrench¾” Open End Wrench11/16” Open End WrenchAdjustable WrenchNeedle Nose Pliers#1 Phillips Screw DriverGrease- Dupont Krytox GPL-207 or equivalentAlcohol7

5. DISASSEMBLY & REASSEMBLYNote: Be sure the work area is clean and free from any materials or particles that maycontaminate parts during the disassembly and reassembly of the blender.Note: Calibration procedures must be performed following servicing of the blender.Note: The primary focus of these instructions is for the standard Hi-Low Flow Blenders.Procedures for other models are essentially the same, but some parts may differ. Input and outputfittings on OEM blenders may differ from what is represented here.5.1. Cover5.1.1. Remove the Blender Outer Cover, if present, by removing the Philips screws (2per side). Earlier style covers may also require any side output fittings to beremoved using a ¾” wrench (refer to 5.9).5.2. Balancing Chambers5.2.1. Using a 5/32” hex wrench,remove the four screws from thetop of the Balancing Chambersand separate the two chambers PRIN010PBAL003from the lower block of theblender.5.2.2. NOTE: Spring and ball will bePDIA004Aloose when cap is removed. Usinga spanner wrench, remove thecaps from each side of one of thePRIN016chamber assemblies.Figure 55.2.3. Remove the ball and springfrom each side and set aside.5.2.4. Remove the o-rings from the caps and also the o-rings from the bottom of thechamber halves and dispose of these.5.2.5. Using the 5/32” hex wrench again, remove the two screws from both sides of thechamber, separate the two halves and remove and discard the diaphragm.5.2.6. Clean the chamber halves with alcohol, paying particular attention to the ballseats.5.2.7. To reassemble, lay one of the halves down on aCenter pin in holeflat surface with the diaphragm cavity facing up.Place the new diaphragm on top and center it withinthe cavity.5.2.8. Place the other half on top of the first half,diaphragm cavity down.5.2.9. Thread two screws into the side facing you farenough to hold the pieces together, but not so tightas to capture the diaphragm. The diaphragm willneed to be further aligned.5.2.10. With the chamber assembly input/output orificesfacing you, take the bottom half of the blender, lay iton it’s side and hold the chamber assembly firmlyFigure 6against it so as to align the bottoms of the twochamber halves in a flat plane (see Figure 6).5.2.11. While holding in this position, reach in with a small tool and move the diaphragmby pushing on the pin until the pin is centered in the hole.5.2.12. Tighten the two screws firmly while taking care to maintain the position of thetwo halves against the blender bottom and the location of the diaphragm in the8

center of the hole.5.2.13. Turn the assembly over and install the other two screws.5.2.14. Lay the assembly down and place a new ball in the seat over the diaphragm pin.Be sure the ball is clean prior to installing.5.2.15. Lightly grease the new o-ring and place over the threads of the cap.5.2.16. Place a small amount of grease on one end of the spring and insert this end intothe hole in the cap. The grease is there to help hold the spring in the hole whileassembling the cap to the chamber.5.2.17. Thread the cap into the chamber with the spring over the ball.5.2.18. Turn over and repeat the ball, o-ring, spring and cap installation on this side.5.2.19. Lightly grease four new o-rings and install them in the appropriate holes in thebottom of the assembly.5.2.20. Set the assembly aside and repeat this entire process for the second balancingchamber assembly.LOWER BLOCKThe lower block may only be thoroughly cleaned internally after complete disassembly. Followthe disassembly instructions below, saving the reassembly of each section until all parts havebeen removed from the block and it has been cleaned and thoroughly dried. It may be cleanedwith alcohol. Once the block is dry, go back to each section and follow the instructions forreassembly of each part into the block.5.3. PROPORTIONING VALVENote: This describes the proportioning valve in the Hi-Low Flow Blender. For the LowFlow Blender, use the methods as described here while referring to the exploded view inthe PARTS sections of this manual.5.3.1. Carefully pry off the end cap on theconcentration-setting knob, loosen thePRIN017nut underneath and remove the knob.PSPR0195.3.2. Using a 5/8” wrench, remove the frontPRIN013PRIN010seat lock nut and remove the front plate.PRIN0045.3.3. With an appropriate spanner, unscrewand remove the front half of theproportioning valve.5.3.4. Tip the block assembly forward and theFigure 7rear valve shaft with spring should fall out.5.3.5. Insert a 1/8” hex wrench into the center ofthe rear seat within the block, unscrew and remove it from the block.5.3.6. Unscrew the valve shaft from the front seat and remove all o-rings from all parts.Do not overlook the small o-ring inside the front valve seat in the spanner hole end.5.3.7. Clean and carefully inspect all parts, paying particular attention to the valve seatareas where the valve shaft tapers make contact with the seats. Replace if theyshow any signs of wear or nicks.5.3.8. Lightly lubricate and reinstall all o-rings. Do not overlook the small o-ring insidethe front valve seat at the spanner hole end.5.3.9. Install the rear seat using the 1/8” hex wrench.5.3.10. Place just enough grease on the end of the new spring to keep it from falling outof the rear valve shaft. Insert the spring into the end of the shaft and install the shaftinto the rear seat, spring end first.5.3.11. Lubricate the threads on the front valve shaft and thread it into the front valve9

seat just far enough so the taper touches the seat.5.3.12. Thread the front seat into the block just far enough that the outer most o-ring iswithin the block.5.4. ALARM SPOOL & BYPASS VALVE5.4.1. Using a spanner, remove thecap from the left side of the blockand then tip the block on its side toremove the spring which is inside.5.4.2. Using a 1/8” hex wrench,remove the alarm adjusting screwfrom the center of the cap.5.4.3. From the opposite side,remove the spool assembly withthe same spanner. Remove theadjusting screw from the center ofthe spool and remove the springthrough the adjusting screwFigure 8opening.5.4.4. Using an appropriate tool, push the shuttle valve out of the spool by inserting thetool through the opening for the adjusting screw and pushing on the end of thevalve. Take extreme care not to mar the inner surface of the spool.5.4.5. Remove all o-rings and thoroughly clean all parts.5.4.6. Lightly lubricate new o-rings and replace per diagram.5.4.7. Insert the shuttle valve back into the spool and push it all the way into theopposite end. Reinstall the spring through the opening for the adjuster screw andreinstall the adjuster, threading it so it is flush with the end of the spool.5.4.8. Install the other adjuster screw into the cap and set the spool assembly, cap withadjuster and second spring to the side.5.4.9. Remove the cap from the back of the block, located in the center of the integralmounting flange. Earlier blenders will have an alarm reed behind this cap. If so,remove it, making note of which side of the reed plate is facing the cap justremoved.5.4.10. Remove the second cap that is within this cavity.5.4.11. Looking deep into this cavity now, beyond the area where the alarm spool wouldnormally be, the seat for the bypass valve may be seen. Using a 5/32” hex wrench,unscrew and remove this seat. If it does not come out attached to the wrench, tipthe block so as to expel it. Watch for a ball and spring to follow it.5.4.12. If the seat came out with the wrench then now tip the block so as to expel theball and spring located in the bottom of this opening.5.4.13. Remove all o-rings from the parts just removed, clean the parts thoroughly andreplace the o-rings with new ones, lubricating lightly before installing.5.4.14. Place the spring back into the bottom of the cavity and then drop the new ball inon top of it.5.4.15. Place the seat on the end of the 5/32” hex wrench and carefully lower it intoplace above the ball. Screw it down and tighten.5.4.16. Reinstall the cap, reed (if present) and end cap. Be sure to reinstall the reed inthe same orientation as previously noted.5.4.17. Reinstall the spool assembly from the left side of the block and screw downsnugly.5.4.18. Turn the block over and drop in the second spring so that it is within the cavity in10

the end of the shuttle valve within the spool.5.4.19. Install the cap with adjuster into this opening making sure the tip of it is properlypositioned within the center of the spring and tighten snugly.5.5. ALARM (bottom mounted)5.5.1. With a ¾” wrench, remove the O2 supply fitting from the bottom of the block.This is a left hand thread so turn it clockwise to remove. Set it aside.5.5.2. Use the same ¾” wrench to remove the air fitting and set it aside. Remove thefilter and duckbill check valve from within the cavity of the air supply fitting.5.5.3. Using soft jaw pliers, remove the alarm housing from the bottom of the block.5.5.4. Remove the o-ring from the housing and discard.5.5.5. Lightly grease the new o-ring and install on the alarm housing.5.5.6. Reinstall the housing into the block.5.6. OXYGEN SUPPLY FITTING with FILTER AND CHECK VALVEPRIN011Note: These check valves are to prevent one gas supply fromcontaminating the other gas supply due to back-flow. It is importantthat the proper operation of the check valves is verified whenever thisfitting is disturbed. Refer to the Calibration & Test Procedure section.PVAL0315.6.1. Remove the O2 supply fitting (refer to 5.5.1).PSPA0095.6.2. Using two ¾” wrenches, separate the two halves of the fitting.This is a left hand thread so turn it clockwise to separate.PFIL0085.6.3. Remove the filter, spacer and duckbill check valve that isPRIN011under the filter and discard.5.6.4. Take the half with the free turning nut on it and insert a 1/8”hex wrench into the nipple within the nut. Hold the other endPRIN010with a ¾” wrench and unscrew the nipple. This thread has athread lock on it so it may require a little effort.5.6.5. Remove all o-rings from all parts and clean the partsthoroughly. Be sure to properly clean the thread lock from thenipple.5.6.6. Lightly grease new o-rings and install on the nipple. Insert thePRIN023nipple through the nut and place a small amount of threadlock on its threads.Figure 95.6.7. Screw the nipple into the hex fitting and tighten. Check for anyexcess thread lock between the nut and hex that may haveflowed out from the threads and clean off, if present.5.6.8. Lightly grease and install new o-rings over the threads of the two halves.5.6.9. Assemble the duckbill check valve, spacer and filter into the fitting as illustrated inthe diagram. If the spacer is black, the duckbill fits into the recessed area of thespacer.5.6.10. Reassemble the two halves and reinstall into the block where it is labeled“OXYGEN”. It is a left thread so it must be turned counterclockwise to install.5.7. AIR SUPPLY FITTING AND FILTER AND CHECK VALVENote: These check valves are to prevent one gas supply from contaminating the other gassupply due to back-flow. It is important that the proper operation of the check valves isverified whenever this fitting is disturbed. Refer to the Calibration & Test Proceduresection5.7.1. Remove the Air supply fitting from the block (refer to 5.5.2).5.7.2. Remove and replace the filter, spacer and duckbill check valve. If the spacer is11, the duckbill fits into the recessed area of the spacer.Remove and discard the o-ring from the Air fitting. Clean the fitting.Lightly grease a new o-ring and replace it over threads of fitting.Install the fitting over the filter in the block.5.8. PRIMARY OUTLET FITTING5.8.1. Using a ¾” wrench, remove the primary outlet fitting from the bottom of the block.Once it is removed, there will be a loose spring insidethe cavity.5.8.2. Remove the check valve plunger that is inside thefitting.5.8.3. Remove all o-rings and clean the plunger and fitting.5.8.4. Lightly grease new o-rings and install them on theplunger and fitting.PRIN0165.8.5. Place the spring, if removed, into the primary outletcavity so it is seated in the recess in the center of thebottom of the cavity.5.8.6. Hold the plunger over the spring so that the shoulderPRIN008on the o-ring end is centered in the spring and lowerthe fitting over the plunger. Screw the fitting into theblock and tighten with the wrench.5.9. AUXILIARY OUTLET FITTING5.9.1. If there is a flowmeter here, go to Step 5.10. If there is a knob here, go to Step5. Using a ¾” wrench, unscrew the auxiliary outlet fitting from the side of the block.Once it is removed, there will be a loose spring inside the cavity.5.9.3. Remove the check valve plunger that isinside the fitting.5.9.4. Remove all o-rings and clean theplunger and fitting.PRIN0115.9.5. Lightly grease new o-rings and installthem on the plunger and fitting.PRIN0105.9.6. If the blender has an outside cover,then finish this procedure after thePRIN016cover has been reinstalled (refer to5.14). Place the spring, if removed,into the auxiliary outlet cavity so it isseated in the opening in the center ofthe cavity.Figure 115.9.7. Hold the plunger over the spring so thatthe shoulder on the o-ring end is centered in the spring and lower the fitting overthe plunger. Screw the fitting into the block and tighten with the wrench.12

5.10.AUXILIARY FLOWMETER WITH ON/OFF5.10.1. This step only applies toblenders with a flowmeter inthis position that can bepushed in and turned.5.10.2. Set the flowmeter to thePRIN012OFF position as instructedby the label on theflowmeter mount.MLAB0425.10.3. Remove the GAS ON/GASPRIN011OFF label.PRIN0105.10.4. Using a 1/16” hex wrench,PRIN032*loosen the two setscrewsPRIN032PRIN004closest to the flowmeterand pull off the flowmeter.5.10.5. Using the same hexFigure 12wrench, loosen the outersetscrews on the remaininghalf of the flowmeter mount and pull this part off. Do not disturb the othersetscrews.5.10.6. Using a ¾” wrench, remove the remaining ON/OFF valve. Once it is removed,there will be a loose spring inside the cavity.5.10.7. Remove the valve stem from the valve bushing.5.10.8. Remove all the o-rings and clean the parts.5.10.9. Lightly grease the new o-rings and install all but PRIN032* according to theillustration. This one will be installed during reassembly.5.10.10. Insert the valve stem into the bushing from the threaded end, leading with theend of the stem with no o-ring installed.5.10.11. With the spring properly positioned in the bottom of the cavity in the blendermanifold, reinstall the valve assembly and tighten it with the ¾” wrench. Press inon the valve stem and verify it moves smoothly against the spring.5.10.12. Slip the first half of the flowmeter mount (with the pins protruding within the innerdiameter) over the valve stem and engage the pins within the slots in the valvebushing. Push it all the way against the bushing so that the o-ring groove on theend of the valve stem is exposed.5.10.13. Lightly grease the remaining PRIN032 that was left off previously and install it onthe end of the valve stem.5.10.14. Now slide this mount back out over the o-ring just installed until the end of it isflush with the end of the valve stem. Tighten the setscrews in this position. Testthe actuation of the ON/OFF valve by pushing in, turning and releasing the mount.It should move without binding.5.10.15. With the valve in the ON position (pushed in and turned clockwise), install theflowmeter onto the valve so that it is upright (parallel to the front of the blender)and tighten the setscrews.5.10.16. Push in and turn the flowmeter to the OFF position. It should be angled to thefront. Adhere the ON/OFF label onto the flowmeter mount so that in the OFFposition, the “GAS ON” portion of the label is facing forward. When the flowmeteris in the ON position, the “GAS OFF” portion of the label should rotate and nowface forward.13

5.11.HIGH/LOW FLOW KNOB5.11.1. This step only applies to blenderswith a knob in this position that canbe pushed in and turned.5.11.2. Set the knob to the “greater than( )” position as instructed by thePRIN011label on the side of the blender.PRIN0105.11.3. Using a 1/16” hex wrench, loosenPRIN032the two setscrews closest to theoutside edge of the knob and pullPRIN004off the knob. Do not disturb theother setscrews.5.11.4. Using a ¾” wrench, remove theON/OFF valve bushing with theslots in it.Once it is removed,Figure 13there will be a loose spring insidethe cavity.5.11.5. Remove the valve stem from the bushing.5.11.6. Remove all the o-rings and clean the parts.5.11.7. Lightly grease the new o-rings.5.11.8. Insert the valve stem into the bushing from the threaded end as in the illustration.5.11.9. With the spring properly positioned in the bottom of the cavity within the blendermanifold, reinstall the valve assembly and tighten it with the ¾” wrench. Press inon the valve stem and verify it moves smoothly in and out against the spring.5.11.10. With the indicator line on the end of the knob pointing upwards and somewhatleft of center, slip the knob over the valve bushing and shaft, engaging the twopins in the knob with the slots in the bushing. Continue to slide the knob onto theshaft just to the point that it bottoms out on the shaft and you can feel it juststarting to push against the spring tension of the shaft. Tighten the knob to theshaft in this position by tightening the two outside setscrews. It is important this isdone properly or maximum flow may not be achieved when the knob is in the “lessthan ( )” position.5.11.11. Test the actuation of the knob by pushing in, turning and releasing it. It shouldmove without binding.5.12.SIDE PORT CAP5.12.1. Using the appropriate spanner, remove the cap onthe side port(s).5.12.2. Remove the o-ring and clean the cap.5.12.3. Lightly grease the new o-ring and replace over thethreads of the cap.5.12.4. Screw the cap back into the block and tighten withthe wrench.PRIN010Figure1414

5.13.MUFFLER5.13.1. From the underside of the block, carefully pry out theretaining star clip and remove the foam muffler.5.13.2. Insert the new muffler into the cavity and press the starclip back into place. Note that the clip has a slightlyconcave form to it. This is to aid insertion andretention.PMUF001MRIN010Figure 155.14.FINAL ASSEMBLY5.14.1. Once the block has been completely reassembled, reinstall the two balancingchambers to the top of the block. Be sure the o-rings are properly fitted into theorifices in the bottom of the chambers.5.14.2. Tighten the four chamber screws using a 5/32” hex wrench.5.14.3. Reinstall the front plate and retaining nut. Leave the nut loose and the knob off forthe calibration procedure to follow.5.14.4. Reinstall the outer cover and then any side output ports removed. Refer to 5.9.15

6. CALIBRATION & TEST PROCEDURETools required:1/8” hex wrenchAdjustable Spanner9/32” nut driver5/8” wrench11/16”

The Bio-Med Air/Oxygen Blender is a precision proportioning device for mixing medical grade air and oxygen to any concentration from 21% to 100% oxygen and delivering it to a variety of respiratory care devices. The blender uses source air and oxygen at a pressure of 50 psi connected to two D.I.S.S