Summary of the content on the page No. 1
PART #461248
READ AND SAVE THESE INSTRUCTIONS
HEAT RECOVERY UNIT
WITH EVAPORATIVE COOLING
®
Models: HRE-20, 45, 55, & 90
INSTALLATION, OPERATION AND MAINTENANCE
MANUAL
RECEIVING AND HANDLING
The HRE is thoroughly inspected and test run at the factory. However, damage may occur during
shipping and handling. Upon delivery, inspect the unit for both obvious and hidden damage.
If damage is found, record all necessary information on the bill of lading and file a claim with
the final carrier. In
Summary of the content on the page No. 2
TABLE OF CONTENTS Storage and Basic Operation . . . . . . . . . . . . . 2 Typical Wiring Diagram . . . . . . . . . . . . . . . . . . 22 . Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Sensors and Lights . . . . . . . . . . . . . . . . . . . 23-24 Lifting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Remote Control Panel & . Wiring . . . . . . . . 25-27 Unit Weights & Recommended Roof Sensors Mounted by Factory . . . . . . . . . . . .
Summary of the content on the page No. 3
INSTALLATION The system design and installation should follow accepted industry practice, such as described in the ASHRAE Handbook . SAFETY WARNING All factory provided lifting lugs must Adequate space should be left around the unit for piping be used when lifting the units . Failure to comply with this safety precaution coils and drains, filter replacement, and maintenance . could result in property damage, Sufficient space should be provided on the side of the serious injury, or death
Summary of the content on the page No. 4
ROOF CURB MOUNTING Rooftop units require curbs to be mounted first . The duct connections must be located so they will be clear of structural members of the building . Roof curb details, including duct location 1. Factory Supplied Roof Curbs dimensions, are available on HRE roof curb Roof curbs are Model GKD, which are shipped in a assembly instructions. knockdown kit (includes duct adapter) and require field assembly (by others) . Assembly instructions are included with the curb . 2. Ins
Summary of the content on the page No. 5
n n n n o o o o i i i i t t t t a a a a t t t t o o o o R R R R n n n n RAIL MOUNTING Rail Layout • Rails designed to handle the weight of the HRE should be positioned as shown on the diagram (rails by others) . • Make sure that rail positioning does not interfere with the supply air discharge opening or the exhaust air intake opening on the HRE unit . Avoid area dimensioned “B” below • Rails should run the width of the unit and extend beyond the unit Turni
Summary of the content on the page No. 6
ELECTRICAL INFORMATION The unit must be electrically grounded in accordance with the current National Electrical Code, ANSI/NFPA No. 70. In Canada, use current C.S.A. Standard C22.1, Canadian Electrical Code, Part 1. In addition, the installer should be aware of any local ordinances or electrical company requirements that might apply . System power wiring must be properly fused and conform to the local and national electrical codes . System power wiring is to
Summary of the content on the page No. 7
TYPICAL CONTROL CENTER COMPONENTS 1 . Main Disconnect (non-fusible, lockable) 5 2 . Motor Starter - Exhaust Air Fan 3 . Motor Starter - Outdoor Air Fan 1 4 . Motor Contactor - Energy Wheel 5 . 24 VAC Control Transformer 6 . 24 VAC Terminal strip 7 . Fuses for blower motors 6 8 . Motor Contactor - Indirect Evap Pump 9 . Motor Contactor - Direct Evap Pump 7 10 . Evap Pump Transformer (115 VAC Secondary) 10 2 3 4 8 9 Exploded Detail of Terminal Strip 7
Summary of the content on the page No. 8
Cassette Slides Out SERVICE CLEARANCES / ACCESS PANEL LOCATIONS HRE-20, 45, 55, and 90 units require minimum clearances for access on all sides for routine maintenance . Filter replacement, drain pan inspection and cleaning, energy wheel cassette inspection, fan bearing lubrication and belt adjustment, are examples of routine maintenance that must be performed . Blower and motor assemblies, energy recovery wheel cassette, coil and filter sections are always provided with a service door or pan
Summary of the content on the page No. 9
DIMENSIONAL DATA / ACCESS DOOR DESCRIPTIONS Exterior Dimensions Model A B C D E F G H I HRE-20 98 50 56 18 28 .5 17 6 14 .25 18 HRE-45 106 69 66 16 41 23 .375 10 .5 13 .375 20 HRE-55 118 70 76 16 59 .5 5 .875 7 .125 21 .25 25 HRE-90 131 85 96 16 78 2 .875 10 24 .5 27 All dimensions shown are in inches . Overall Exterior Dimensions Model Width Overall Width Overall Length (including Lifting Lugs) (with Exhaust Hood) (with Outdoor Air Hood) HRE-20 59 .5 75 116 HRE-45 69 .5 86 122 HRE-55 7
Summary of the content on the page No. 10
EVAPORATIVE COOLING MODULES Mount the heat recovery unit level to ensure proper Indirect Evaporative Cooler (Exhaust/Scavenger Airstream) operation and water drainage . Piping should be of adequate size to provide sufficient supply of water to meet the maximum demand of the evaporative coolers . EVAP MODULE INSTALLATION 1 . After the energy recovery unit is set in place, run the overflow and drain lines to the exterior fittings on the evaporative cooler (drain & overflow connections at uni
Summary of the content on the page No. 11
7 . Verify that both airflow and system static pressure are in agreement with the specifications . If these conditions are met, check for water carry over from the discharge side of the media . If carry over is observed, check the distribution header for holes or tears and the water standoff tube for blockage . 8 . After all final adjustments are made, remove the jumper wires, connect “call for cooling” signal, and replace all access panels . The unit is now ready for operation . Bleed-Off
Summary of the content on the page No. 12
AUTO DRAIN AND FILL WITH FREEZE PROTECTION WATER CONTROL OPTIONS FOR EVAPORATIVE COOLING THE SYSTEM WILL AUTOMATICALLY DRAIN THE SUMP TANK AND FILL IT WITH FRESH WATER AT THE FIELD ADJUSTABLE INTERVALS, TYPICAL SETTINGS ARE t1 = 24HRS t2 = 10 MIN. WITH THE DIP SWITCH IN THE DOWN POSITION. THIS FLUSHES MINERAL BUILD-UP AND DEBRIS FROM THE TANK TO PROMOTE LOW MAINTENANCE AND INCREASE MEDIA PAD LIFE. IN ADDITION, THE SYSTEM WILL PROTECT THE EVAPORATIVE COOLER FROM FREEZING BY DRAINING THE SUMP
Summary of the content on the page No. 13
AUTO DRAIN AND FILL WITH FREEZE PROTECTION THE SYSTEM WILL AUTOMATICALLY DRAIN THE SUMP TANK AND FILL IT WITH FRESH WATER AT THE FIELD ADJUSTABLE INTERVALS, TYPICAL SETTINGS ARE t1 = 24HRS t2 = 10 MIN. WITH THE DIP SWITCH IN THE DOWN POSITION. THIS FLUSHES MINERAL BUILD-UP AND DEBRIS FROM THE TANK TO PROMOTE LOW MAINTENANCE AND INCREASE MEDIA PAD LIFE. IN ADDITION, THE SYSTEM WILL PROTECT THE EVAPORATIVE COOLER FROM FREEZING BY DRAINING THE SUMP TANK AND SUPPLY LINE WHEN THE OUTSIDE TEMPERA
Summary of the content on the page No. 14
DRAIN AND OVERFLOW CONNECTION LOCATIONS Connection Locations - in inches Model Outdoor Air Side Exhaust Side A B C D A B C D HRE-20 4 .00 2 .875 40 .75 42 .25 4 .00 2 .875 52 .25 53 .75 HRE-45 6 .25 5 .125 42 .625 44 .125 6 .25 5 .125 56 .50 58 .00 HRE-55 6 .375 5 .125 53 .00 54 .50 6 .375 5 .125 66 .375 67 .875 HRE-90 6 .375 5 .125 47 .25 48 .50 6 .375 5 .125 71 .00 72 .25 Outdoor Air OUTDOOR AIR INTAKE COMPARTMENT OUTDOOR AIR DISCHARGE COMPARTMENT A B C 3/4 INCH DIRECT EVAP DRAIN AND OVERFLOW
Summary of the content on the page No. 15
TROUBLESHOOTING FOR EVAPORATIVE MODULE Symptom Solution Insufficient water A . Check water level in base pan . The volume or recirculation level should be at 1 inch . pump not operating B . Check the pump filter at the inlet . C Clean the filter if clogged or dirty . C . If pump is not operating, check wiring for loose connections and proper voltage . D . Clogged or worn out pump . E . Clogged header . Header F . Water flow adjustment device Detail Irregular water Water distribution
Summary of the content on the page No. 16
EVAPORATIVE COOLING MAINTENANCE Regularly scheduled maintenance is the key to peak c) Open evaporative cooling section door performance, minimized cost, and extended life of d) Flush distribution headers and media for 20 the evaporative cooler . The following is a checklist of minutes items that need to be looked at on a regular basis . e) Turn off pumps and drain all water distribution piping, headers, etc . 1 . The media should be checked for mineral and f) Dry media completely by running
Summary of the content on the page No. 17
OPTIONAL ACCESSORIES Electric Heater Application/Operation Factory installed electric heaters can be provided for preheat and/or post-heat . An electric preheater warms the outdoor air prior to the energy recovery wheel to prevent frosting on the wheel . An electric post-heater warms the air leaving the energy recovery wheel to a user specified discharge temperature . Electric heaters are available in 208, 230, or 460 Vac (refer to heater nameplate for voltage) . Preheaters: Preheaters are st
Summary of the content on the page No. 18
OPTIONAL ACCESSORIES Frost Control Application/Operation Extremely cold outdoor air temperatures can cause moisture condensation and frosting on the energy recovery wheel. Frost control is an optional feature that will prevent/control wheel frosting. Three options are available: 1) Timed Exhaust frost control Indoor RH @ 70º F Frost Threshold Temp 2) Electric preheat frost control 20% 2º F 3) Modulating wheel frost control 25% 7º F All of these options are provided with a th
Summary of the content on the page No. 19
OPTIONAL ACCESSORIES Economizer Application/Operation The energy recovery wheel operation can be altered to take advantage of economizer operation (free cooling) . Two modes are available: 1) De-energizing the wheel or 2) Modulating the wheel. A field supplied call for cool (Y1) is required . De-energizing the wheel is accomplished with a signal from a Temperature or Enthalpy sensor mounted in the supply air inlet compartment . This Primary sensor will de-energize the energy
Summary of the content on the page No. 20
OPTIONAL ACCESSORIES Variable Frequency Drives for Blowers Optional factory installed, wired, and programmed variable frequency drives (VFD) may have been provided for modulating or multi-speed control of the blowers . One VFD is provided for each blower (outdoor air and exhaust) . The VFDs provided are either Yaskawa model E7 or model GPD305 . Refer to the tables on the next page for factory settings and field wiring requirements . Refer to the unit control center for unit specific wiring d
