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4

Refrigerant Coils

Refrigerant coils should be kept clean to maintain max-
imum performance. If fins become dirty, clean with 
cold water and detergent, or one of the commercially 
available chemical coil cleaners. Rinse coils thorough-
ly after cleaning.

1.  Follow steps 1-4 from Steam and Water Coil 

cleaning procedure preceding.

2.  Mix a high quality coil cleaning detergent with 

water accordance to the manufacturer’s instruc-
tions. If the detergent is strongly alkaline after 
mixing (pH 8.5 or higher), it must contain an in-
hibitor. Carefully follow the detergent manufac-
tures instructions on the use of the product.

3.  Place the mixed solution in a garden sprayer or 

high-pressure sprayer. If a high pressure sprayer 
is used note the following:

•  Maintain a minimum nozzle spray angle of 

15 degrees.

•  Spray perpendicular to the coil face.

•  Protect other areas of the air handler and in-

ternal controls from contact with moisture or 
the cleaning solution.

•  Keep the nozzle at least 6 inches from the 

coil.

•  Do not exceed 600 psi.

4. 

Spray the leaving airside of the coil first, then the 

entering airside. Use a block-off to prevent spray 
from going through the coil and into dry sections 
of the unit and/or system ductwork. Carefully fol-
low the cleaning solution manufacturer’s usage 
instructions.

5.  Thoroughly rinse both sides of the coil and the 

drain pan with cool, clean water.

6.  Repeat steps 4 and 5 as necessary.

7. 

Straighten any coil fins that may have been dam

-

aged during the cleaning process with a fin comb.

8. 

Confirm that the drain line remains open follow

-

ing the cleaning process.

9.  Replace all panels and parts and restore electrical 

power to the unit.

10.  Use caution to assure that any contaminated ma-

terial does not contact other areas of the unit or 
building.

Properly dispose of all contaminated ma-
terials and cleaning solutions. 

Winterizing Water Coils

Due to air stratification, failure of outdoor air damp-
ers and/or preheat controls, coil freeze-up can occur. 
Scheduled draining of water cooling coils for win-
ter shutdown cannot be depended upon as insurance 
against interior tube freezeup. Freeze-up will result in 
severe coil damage. It is recommended that all coils be 
drained as thoroughly as possible and then treated in 
the following manner.

Fill each coil independently with an anti-freeze solu-
tion using a small circulating pump and again thor-
oughly drain. Check freezing point of anti-freeze be-
fore proceeding to next coil. Due to a small amount of 
water always remaining in each coil, there will be a di-
luting effect. The small amount of anti-freeze solution 
remaining in coil must always be sufficient enough to 
prevent freeze-up.

Carefully read instructions for mixing 
anti-freeze solution used. Some products 
will have a higher freezing point in its 
natural state than when mixed with water. 
The freezing of coils is not the responsibil-
ity of ENVIRO-TEC®. 

OPERATING GUIDELINES

Operating Limits

Do not exceed the operating limits in 

Table 7 on page 

30

. A fan wheel that is operated beyond the rpm and 

temperature limits shown may suffer permanent distor-
tion or failure.

Vibration Levels

Each unit that is shipped has been trim-balanced to 
function properly. Although the factory requirements 
are much tighter, to assure satisfactory operation after 
enduring the rigors of shipping and installation. The 
following is accepted industry guidelines for field-bal-
ancing fans found in 

Table 8 on page 30

.

ENVIRO-TEC

29

SECTION 4 - PERIODIC MAINTENANCE AND SERVICE

FORM ET102.19-NOM1 (0521)

Содержание MQL B Series

Страница 1: ...MODEL MQL SERIES B INSTALLATION OPERATION MAINTENANCE INDOOR AIR HANDLING UNIT Supersedes ET102 19 NOM1 517 Form ET102 19 NOM1 0521...

Страница 2: ...r with and comply with all applicable governmental standards and regulations pertaining to the task in question SAFETY SYMBOLS The following symbols are used in this document to alert the reader to sp...

Страница 3: ...ushing or dismember ment injuries HOT PARTS HAZARDS Electric Resis tance heating elements must be discon nected prior to servicing Electric Heaters may start automatically disconnect all power and con...

Страница 4: ...y rigging and lifting equipment All assemblies must be adequately se cured during lifting and rigging by temporary supports and restraints until equipment is permanently fastened and set in its final...

Страница 5: ...rnal Isolation 15 External Isolation 15 Service Clearance 15 Panel Removal 15 General Piping 15 DX Connection Steps 16 In the field 16 Notes 16 Condensate Drain 16 Electrical Installation 16 INSPECTIO...

Страница 6: ...25 Mounting Straight Bore Sheaves 25 Mounting Split Tapper Sheaves 26 Adjust Variable Pitched Sheaves 26 Belts 27 Adjusting Belt Tension 27 How to Increase Belt Life 27 Coils 28 Steam Hot Water and Ch...

Страница 7: ...Sheaves 21 FIGURE 12 Sheave Alignment 22 FIGURE 13 Split Tapper Sheave Mounting 22 FIGURE 14 Belt Tension 23 TABLE 1 Minimum Hex Head Bolt Torque In Lb Ft Grade 5 Bolt 18 TABLE 2 Recommended Greasing...

Страница 8: ...THIS PAGE INTENTIONALLY LEFT BLANK ENVIRO TEC 8 FORM ET102 19 NOM1 0521 LIST OF FIGURES...

Страница 9: ...To ensure the assembled MQL modules are in the proper sequence each module has an identifying code and an airflow direction label The proper assembly sequence is listed on the supply fan nametag The...

Страница 10: ...balanced Rough handling may cause bearing misalignment and or shaft damage STORAGE To transfer equipment from truck to storage site refer to Rigging And Handling on page 9 If a forklift is used lift...

Страница 11: ...e actuator if the damp ers are the same size If the dampers are different sizes they must be driven by individual actuators and con trolled separately b Remove all shipped loose parts from job site to...

Страница 12: ...THIS PAGE INTENTIONALLY LEFT BLANK ENVIRO TEC 12 FORM ET102 19 NOM1 0521 Section 1 introduction...

Страница 13: ...ed from a ceil ing a base rail angle iron or channel must support the equipment The MQL product line is not designed to be suspended from the top of the equipment Be fore hanging the equipment all fie...

Страница 14: ...Left Hand Fan Access Door Figure 7 HAND IDENTIFICATION ENVIRO TEC 14 FORM ET102 19 NOM1 0521 Section 2 installation...

Страница 15: ...oil module is also isolated the piping must be isolated or have a flexible connection to prevent coil header damage due to equipment movement All piping wiring ductwork and external connections must b...

Страница 16: ...at pump condensing units but require the addition of fittings or refrigerant specialties to be furnished and installed by others Condensate Drain All condensate drains must have a trap installed This...

Страница 17: ...l Outside Air For Freeze Protection Proper Supply Return Grille Type Size Used Insulate All Ductwork As Required Verify All Ductwork Is Complete Dampers And Filters Are Installed Prior To Startup E EL...

Страница 18: ...INTENTIONALLY LEFT BLANK ENVIRO TEC 18 FORM ET102 19 NOM1 0521 Section 2 installation...

Страница 19: ...nly qualified individuals should perform these tasks Before entering the fan section make sure that the fan electrical power source is disconnected locked and tagged out in the OFF position 1 Check th...

Страница 20: ...pment 7 Manually rotate motor shaft to ensure that it ro tates freely 8 Replace all panels that were removed during in stallation 9 Momentarily apply power and check direction of rotation of motor sha...

Страница 21: ...sheaves Tighten sheave set screws to the proper torque see Table 1 on page 22 Check and adjust fan belt tension Tighten electrical connections Inspect coils for dirt build up or coil freeze up Every...

Страница 22: ...posal of their product 6 Immediately rinse the drain pan thoroughly with fresh water to prevent potential corrosion from the cleaning solution of the drain pan and drain line components 7 Allow the un...

Страница 23: ...ch conforms to NLGI Number 2 for consis tency See Table 2 on page 23 Table 3 on page 23 and Table 4 on page 23 for recommended greasing intervals operating range and bearing grease capacities Table 2...

Страница 24: ...of operation It is important to remember that this recommendation is base of average use Refer to Table 2 on page 23 for additional information Types of Grease A high grade ball or roller bearing grea...

Страница 25: ...5 The sheave should be close to the motor as possible with setscrew A in full contact with the key If the setscrew a is not fully in contact with key the sheave assembly could come off 4 Be sure that...

Страница 26: ...ft 8 Tighten capscrews progressively with wrench Dothis following a star pattern taking a partial turn on each capscrew successively until all are tight see Table 1 on page 22 for proper torque Do not...

Страница 27: ...be used to calculate the belt span LD14003 2 2 2 d D C Span C Center distance shaft to shaft D Driver sheave large sheave pitch diameter d Driver sheave small sheave pitch diameter 2 Calculate deflect...

Страница 28: ...urface of the coil reduces its ability to transfer heat that can result in reduced performance and increased operating energy costs If the dirt on the surface of the coil becomes wet which commonly oc...

Страница 29: ...10 Use caution to assure that any contaminated ma terial does not contact other areas of the unit or building Properly dispose of all contaminated ma terials and cleaning solutions Winterizing Water C...

Страница 30: ...ON LEVELS FAN SPEED RPM VIBRATION 800 or less 5 mils maximum displacement 801 or greater 20 in sec Maximum velocity Note Excessive vibration from any cause contributes to premature fan and motor beari...

Страница 31: ...l applications to prevent retaining con densate in the coil Generally the vacuum breaker is to be connected between the coil inlet and the return main the vacuum breaker should be open to the atmosphe...

Страница 32: ...se fresh air dampers if steam supply pressure falls below minimum specified Water Heating Coils 1 Water supply and water return connections extend through the end panel of the coil section All con nec...

Страница 33: ...k bear ing lubricant MOTOR STALLS Open phase Check line for an open phase Overloaded motor Reduce load or replace with larger motor Low line voltage Check voltage across AC line Correct voltage if pos...

Страница 34: ...ignment Loosen bearing setscrews and realign see Fig 10 Inadequate lubrication Grease bearing s LOW COIL CAPACITY CHILLED WATER Air is bypassing coil Prevent bypass with block offs Coil tubes are bloc...

Страница 35: ...5 ENVIRO TEC 35 Section 5 TROUBLESHOOTING FORM ET102 19 NOM1 0521...

Страница 36: ...Catalog ET102 19 NOM1 0521 Supersedes ET102 19 NOM1 517 ENVIRO TEC is a mark and or registered mark Unauthorized use is strictly prohibited 2021 Johnson Controls www enviro tec com...

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