Follow all safety codes. Wear safety glasses and work gloves. Use a quenching cloth for brazing, and place a fire extinguisher close to the work area. RL Series Heat Pumps — 8733842393 (2024/05)
Sheet metal parts may have sharp edges or burrs. Use care Risk of Fire! and wear appropriate protective clothing and gloves when Flammable Refrigerant Used—Dispose of properly in handling parts. accordance with federal or local regulations. RL Series Heat Pumps — 8733842393 (2024/05)
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If a compressor is removed from this unit, refrigerant circuit oil will remain in the compressor. To avoid leakage of compressor oil, refrigerant lines of the compressor must be sealed after it is removed. RL Series Heat Pumps — 8733842393 (2024/05)
CABINET CONSTRUCTION: None A — G90 Steel / 1/2" 1.5 LB Dual-Density Fiberglass ELECTRICAL OPTIONS: X — APPLICATION: As Default for Non-Used Electrical Codes G — Extended Range (Geothermal) Fig. 1 Model Nomenclature RL Series Heat Pumps — 8733842393 (2024/05)
RL series units are offered with a wide range of factory-installed options including: internal 2-way valves; DuoGuard™ air coils; 2“4-sided filter racks; MERV 13 filters (with constant airflow ECM motors);...
Note: Maximum and minimum operating limits may not be combined. Refer to Engineer Submittal Sheet on the product information page. (See the QR code on the back page of the IOM). Acronyms: LWT: Leaving Water Temperature EWT: Entering Water Temperature Table 2 Operating Limits RL Series Heat Pumps — 8733842393 (2024/05)
Note any visible damage or shortage on all copies of the freight bill. Concealed damage not discovered until after removing the units from packaging must be reported to Bosch by the original purchaser by filing a claim at: https://claims.bosch-homecomfort.us...
Where access to side panels is limited, pre-removal of the control box side-mounting screws may be necessary for future servicing. NOTICE DO NOT use RL series units for temporary heating, air NOTICE conditioning or ventilation during construction, especially when plastering, sanding, or painting. Care should be taken to RL series units are not approved for outdoor installation;...
RL heat pumps feature fold-out return and supply air duct flanges. These fold-out flanges come folded in from the factory to The supply air location on RL Series Horizontal units can be field allow the heat pumps to more easily fit through doorways and converted from end blow to straight through or vice-versa.
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Horizontal units installed above the ceiling must conform to all local codes. An auxiliary drain pan, if required by code, must be at least four inches larger than the bottom perimeter of the heat pump. Fig. 5 Blower Configuration 12 | RL Series Heat Pumps — 8733842393 (2024/05)
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If the unit is located in a crawl space, the bottom of the unit must be at least four inches above grade to prevent flooding of the electrical parts due to heavy rains. Fig. 8 Screw Locations | 13 RL Series Heat Pumps — 8733842393 (2024/05)
Fig. 10. DANGER Fig. 11 Condensate Drain Installation The rods must be securely anchored to the ceiling. Fig. 10 Threaded Rod 14 | RL Series Heat Pumps — 8733842393 (2024/05)
5.7 Duct System Never use flexible hoses of a smaller inside diameter than that All RL Series models are provided with a supply air outlet collar of the water connections on the unit. and return air duct flange to facilitate duct connections.
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Occasionally these valves produce a flow noise that can be reduced by applying some back pressure. To accomplish this, slightly close the leaving isolation valve. 16 | RL Series Heat Pumps — 8733842393 (2024/05)
Field wiring must be installed by qualified and trained personnel. WARNING Power to the unit must be within the operating voltage range indicated on the unit’s nameplate or on the performance data sheet. | 17 RL Series Heat Pumps — 8733842393 (2024/05)
Strain-Relieving Flexible Conduit as Shipped from the Factory The reversing valve on the RL series is energized when the unit is in cooling mode. Position thermostats on an interior wall away from supply ducts. Wire Clamp...
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Because remote temperature sensors measure resistance, very long cable runs can cause slight errors in the measurement. For the highest temperature reading accuracy, avoid exceeding the maximum recommended wire lengths show in Table 6. | 19 RL Series Heat Pumps — 8733842393 (2024/05)
Anti-freeze solutions must be used low loop (Refer to Fig. 16) temperatures are expected to occur. Operation of an RL Series unit on a closed loop application requires the extended range option. NOTICE Refer to the GLP installation manuals for more specific Closed-loop and pond applications require specialized design instructions.
Fouling due to iron bacteria can also pose problems in some open loop installations. Iron bacteria fouling can quickly degrade system performance and plug heat exchangers. Air in the water system will greatly accelerate the fouling or corrosion process. | 23 RL Series Heat Pumps — 8733842393 (2024/05)
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< 10 ppm, < 600 µm size** Erosion Maximum Water Velocity 6 ft/sec 6 ft/sec * No "rotten egg" smell present at < 0.5 ppm H ** Equivalent to 30 mesh strainer Table 7 Water Quality Table 24 | RL Series Heat Pumps — 8733842393 (2024/05)
There is a time delay before the compressor will start. NOTICE A compressor running in reverse has a noisier than normal operation and a lower current draw than its rated value. | 25 RL Series Heat Pumps — 8733842393 (2024/05)
Allow five minutes between tests for the pressure or reversing valve to equalize. 1. Turn thermostat to lowest setting and set thermostat switch to HEAT position. 2. Slowly turn the thermostat to a higher temperature until the compressor activates. 26 | RL Series Heat Pumps — 8733842393 (2024/05)
When a malfunction light is used for diagnostic purposes, the [10] UPM Settings DIP Switch (SW1) connection is made at the dry contact connection terminals of [11] A2L Sensor the UPM board. [12] 24VAC Power Common | 27 RL Series Heat Pumps — 8733842393 (2024/05)
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30 seconds, the controller will shut down the compressor and enter into a soft-lockout condition. The default freeze limit trip is 25°F. 28 | RL Series Heat Pumps — 8733842393 (2024/05)
Test function. When it is set to “ON,” it will reduce all time delays settings to 10 seconds during troubleshooting or verification of unit operation. ( Refer to Fig. 17, item [10]) Refer to Fig. 20) | 29 RL Series Heat Pumps — 8733842393 (2024/05)
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120 seconds, the controller will shut the compressor down and enter into a soft-lockout condition. Both the status LED and the alarm contact will be active. The 30 | RL Series Heat Pumps — 8733842393 (2024/05)
Fan Motor 13 Fan Motor 13.1 Permanent Split Capacitor Motors (PSC) The standard motor for all RL series heat pumps is a three-speed PSC motor. If a speed change is required, follow the instructions below: 1. Disconnect power to the heat pump.
• air temperature problems. Use of the pressure and temperature charts for the unit may be required to properly determine the cause. | 35 RL Series Heat Pumps — 8733842393 (2024/05)
Intrinsically-safe components must be replaced. for the purpose and to the correct specification. At all times the manufacturer's maintenance and service guidelines must be followed. If in doubt, consult Bosch service and support for 16.8 Check Cabling assistance. Check that cabling will not be subject to wear, corrosion,...
Ensure that the refrigerating system is earthed prior to charging the system with refrigerant. Be sure to label the system when charging is complete (if not already). Use extreme care not to overfill the refrigerating system. | 37 RL Series Heat Pumps — 8733842393 (2024/05)
Remove the three screws positioned above the motor. Drop down and slide off the welded pins situated on the opposite side from the motor. (See Fig. 24.) 38 | RL Series Heat Pumps — 8733842393 (2024/05)
Before carrying out this procedure, it is essential that the Ensure that there are labels on the equipment stating the technician is completely familiar with the equipment and all its equipment contains flammable refrigerant. detail. | 39 RL Series Heat Pumps — 8733842393 (2024/05)
No or low air flow Inspect the air coil for dirt/debris. blinking two (2) times? Check duct work—Are dampers closed or blocked? Low pressure fault— Check refrigerant pressure with a gauge set. Low refrigerant 40 | RL Series Heat Pumps — 8733842393 (2024/03)
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Check air filter and return air duct work for times? Condensate fault— blockage. Check that there is adequate space Blocked return air between the return air opening and walls or other obstructions on free return applications. | 41 RL Series Heat Pumps — 8733842393 (2024/03)
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If not check the resistance of the compressor Burned out windings using the values shown in the compressor compressor characteristics chart. Note that the compressor must be cool (70° F) when checking the windings. 42 | RL Series Heat Pumps — 8733842393 (2024/03)
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Check that the wires from the thermostat to the energized Loose wire on “O” unit are securely connected and that the wires terminal from the electrical box to the reversing valve are connected. | 43 RL Series Heat Pumps — 8733842393 (2024/03)
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Low refrigerant capacity High humidity Check unit performance against building load Unit oversized calculations. Short cycling Poor thermostat Make sure that the thermostat is not located near location a supply air duct. 44 | RL Series Heat Pumps — 8733842393 (2024/03)
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Clean/descale water coil. water coil elevating heat pressure Low air flow Check filter. elevating head Increase fan speed. pressure Fast-closing valves Change valves to slow-close type. Water hammer installed Table 12 Unit Troubleshooting | 45 RL Series Heat Pumps — 8733842393 (2024/03)
All values are based upon pure water at 70° F. PD (psi) = [ (Wtr Flow (gpm)^1.8) * k const ] / 2.31 PD (psi) = (Wtr Flow (gpm) / CV)^2 * Specific Gravity Table 14 Water-Side Pressure Drop Table 52 | RL Series Heat Pumps — 8733842393 (2024/05)
60.4 90.6 85.0 60.4 60.2 RL070 HZ 134.4 38.6 41.1 27.3 27.4 41.1 38.6 27.4 27.3 *The front is the control box end of the unit. Table 16 Corner Weights (HZ) 54 | RL Series Heat Pumps — 8733842393 (2024/05)
20.1 Single-Stage, Single-Phase, Standard Unit with Permanent Split Capacitor (PSC) Motor Fig. 26 Single-Stage, Single-Phase, Standard Unit with PSC Motor FOR REFERENCE ONLY Actual unit wiring may vary from this example. Always refer to the wiring diagram attached to the unit. 56 | RL Series Heat Pumps — 8733842393 (2024/05)
Return) Table 18 Vertical (VT) Unit Dimensions • Specifications subject to change without notice. • All dimensions within ±0.125". • Overall unit dimensions do not include filter rack or duct flanges. | 57 RL Series Heat Pumps — 8733842393 (2024/05)
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Dimensional Drawings Fig. 27 Vertical (VT) Unit Drawings 58 | RL Series Heat Pumps — 8733842393 (2024/05)
• All dimensions within ±0.125". • Overall unit dimensions do not include filter rack or duct flanges. • Unit sizes 015–070 can be field converted between end blow and straight-through supply air configurations. | 59 RL Series Heat Pumps — 8733842393 (2024/05)
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Dimensional Drawings Fig. 28 Horizontal (HZ) Units Dimensional Drawings 60 | RL Series Heat Pumps — 8733842393 (2024/05)
Note: The local electric codes may require 36" or more clearance at the electrical control box Motor access clearance 18” Minimum 24” Optimum Fig. 29 Vertical and Horizontal Cabinet Service Clearance | 61 RL Series Heat Pumps — 8733842393 (2024/05)
Decommissioning — Means the final shut-down and removal from operation or usage of a product or piece of equipment containing fluorinated greenhouse gases. Discharge Pressure — Referring to the pressure leaving compressor. 62 | RL Series Heat Pumps — 8733842393 (2024/05)
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Additional Product Information Page To see additional product information and documentation, please visit the product page: www.bosch-homecomfort.com/us/ or scan the QR code below. Bosch Thermotechnology Corp. 65 Grove Street Watertown, MA 02472 Tel: +1 (800) 283-3787 Fax: +1 (603) 965-7568...