Bosch LM Series User manual

Installation, Operation and Maintenance Manual
LM Series Heat Pump
8 733 905 315 (2013/9)
LM024 | LM036 | LM048 | LMO60 | LM070

2| LM Series Heat Pump
LM Series Heat Pump8 733 905 315 (2013/9) Subject to change without prior notice
CONTENTS
Standard package.............................................................. 4
General Description........................................................... 4
Moving and Storage........................................................... 5
Initial Inspection ............................................................... 5
Location............................................................................ 5
Blower Configurability....................................................... 5
Return and Discharge Duct Flanges .................................... 6
Mounting Vertical Units ..................................................... 6
Mounting horizontal Units .................................................. 6
Condensate Drain.............................................................. 7
Duct System...................................................................... 7
Piping............................................................................... 8
Electrical .......................................................................... 8
Safety Devices and the UPM Controller ......................... 10
ECM INTERFACE BOARD- Constant Airflow Motor (Option)..
13
Dehumidification Method Selector ............................... 14
Constant Torque Motors (ECM) ........................................ 14
Options........................................................................... 15
Hot Gas Reheat (HGRH).............................................. 15
Electric Heat ............................................................. 15
Constant Airflow Motor............................................... 15
Fan Status Switch ...................................................... 15
Pump Status Switch ................................................... 15
DPS Water Flow Proving ............................................. 16
Valve End Switch ....................................................... 16
Pump Relay............................................................... 16
Sequence of Operation .................................................... 16
Cooling Mode ............................................................ 16
Heating Mode............................................................ 16
Application Considerations .............................................. 18
Cooling Tower/Boiler Systems ..................................... 18
Geothermal Systems .................................................. 20
System Checkout ............................................................ 21
Unit Start-up ................................................................... 21
Maintenance ................................................................... 21
Access to Internal Components for Vertical (VT) Units ..... 22
Unit Check-Out Sheet ...................................................... 23
Customer Data .......................................................... 23
Unit Nameplate Data .................................................. 23
Operating Conditions ................................................. 23
Auxiliary Heat............................................................ 23
Troubleshooting ..............................................................24
Electronic Thermostat Installation ....................................29
Operating Temperatures and Pressures ............................30
Airflow Tables..................................................................35
Wiring Diagrams ..............................................................37
WIRING HARNESS DRAWINGS ..........................................50
Dimensional Drawings......................................................54
Horizontal - Straight Through .......................................55
Horizontal - Hanging bracket location ............................56
Vertical.....................................................................57
Notes ..............................................................................58

| 3LM Series Heat Pump
8 733 905 315 (2013/9)Revised 09-13
MODEL NOMENCLATURE
LM 024 - 1 VT C - F L T - T A
LM
Size Revision Level
024 A - Current
036
048 Fan/Motor Options
060 A - Constant Airflow ECM
070 T - Constant Torque ECM
Voltage Discharge Air Configuration
1 208-230/60/1 T - Top (VT only)
2 277/60/1 S - Straight (HZ only)
3 208-230/60/3 E - End (HZ only)
4 460/60/3
Return Air Configuration
Cabinet Configuration
L - Left
HZ - Horizontal
R - Right
VT - Vertical
Water Connections
Coax Options
F - Front
C - Copper
N - Cupro-Nickel
Installation and servicing of this equipment
can be hazardous due to system pressure
and electrical components. Only trained
and qualified personnel should install,
repair, or service the equipment.
Before performing service or maintenance
operations on the system, turn off main
power to the unit. Electrical shock could
cause personal injury or death.
When working on equipment, always
observe precautions described in the
literature, tags, and labels attached to the
unit. 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.
All refrigerant discharged from this unit
must be recovered WITHOUT EXCEPTION.
Technicians must follow industry accepted
guidelines and all local, state, and federal
statutes for the recovery and disposal of
refrigerants. 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.
To avoid equipment damage, DO NOT use
these units as a source of heating or cooling
during the construction process. Doing so
may affect the unit’s warranty. The
mechanical components and filters will
quickly become clogged with construction
dirt and debris, which may cause system
damage.

4| Standard package LM Series Heat Pump
LM Series Heat Pump8 733 905 315 (2013/9) Subject to change without prior notice
STANDARD PACKAGE
Figure # 1
[1] LM Series Water-to-Air Heat Pump
[2] Installation and Operation Manual
[3] Hanging Bracket Kit (Hz Units Only)
GENERAL DESCRIPTION
LM Series Water-to-Air Heat Pumps provide the
best combination of performance and efficiency
available. All units are performance certified to
American Heating and Refrigeration Institute
(AHRI) ISO Standard 13256-1. All LM Water-to-Air
Heat Pumps conform to UL1995 standard and are
certified to CAN/CSA C22.1 No 236 by Intertek-
ETL.
The Water-to-Air Heat Pumps are designed to
operate with entering fluid temperature between
20°F to 90°F in the heating mode and between
30°F to 120°F in the cooling mode.
LM Series Water-to-Air Heat Pumps are available in
Vertical (VT) and Horizontal (HZ) configurations.
VT and HZ units Discharge Air Orientation is Field
Configurable with the purchase of a separate kit.
Several factory installed options are available:
Hot Gas Reheat, Electric Heat, Sound Package,
Smart Start, Constant Airflow Blower Motor, 2” 4-
sided filter racks, MERV 8 & 13 filters, Differential
Pressure Switch (DPS) Water Flow Proving Switch,
Auxiliary Pump Relay, Air Flow Proving Sensor,
Zone Valve and Internal Water Pump. See Pg#15
for more detail.
Safety devices are built into each unit to provide
the maximum system protection possible when
properly installed and maintained. Each unit has an
external LED error code display, allowing unit
diagnosis without opening the cabinet.
Basic Horizontal Unit layout and connections are
shown in Figure #2 . For more detail on both the
Vertical and Horizontal units, refer to the
Dimensional Drawings on Pg#55 through Pg#58.
50° Minimum Entering Water Temperature
(EWT) for well water applications with sufficient
water flow to prevent freezing. Antifreeze
solution is required for all closed loop
applications. Cooling Tower/Boiler and
Geothermal applications should have sufficient
antifreeze solution to protect against extreme
conditions and equipment failure. Frozen water
coils are not covered under warranty. Other
equivalent methods of temperature control are
acceptable.
1
2
3
Electric Heat is available as a factory installed
option ONLY.

Moving and Storage | 5LM Series Heat Pump
8 733 905 315 (2013/9)Revised 09-13
Figure # 2 Left-Hand Unit (Right-Hand Unit is opposite view)
[1] Air handler access panel
[2] Condensing section access panel
[3] Condensate drain connection
[4] Water connection
[5] Electrical connection knockout
[6] Electric Heat electrical connection knockout
(Optional)
[7] Blower outlet (Supply Air)
[8] LED Error Code
MOVING AND STORAGE
If the equipment is not needed for immediate
installation upon its arrival at the job site, it should
be left in its shipping carton and stored in a clean,
dry area. Units must only be stored or moved in the
normal upright position as indicated by the “UP”
arrows on each carton at all times.
INITIAL INSPECTION
Be certain to inspect all cartons or crates on each
unit as received at the job site before signing the
freight bill. Verify that all items have been received
and that there are no visible damages; note any
shortages or damages on all copies of the freight
bill. In the event of damage or shortage, remember
that the purchaser is responsible for filing the
necessary claims with the carrier. Concealed
damages not discovered until after removing the
units from the packaging must be reported to the
carrier within 24 hours of receipt.
LOCATION
Locate the unit in an indoor area that allows easy
removal of the filter and access panels, with
enough room for service personnel to perform
maintenance or repair. Provide sufficient room to
make fluid, electrical, and duct connection(s). If
the unit is located in a confined space such as a
closet, provisions must be made for return air to
freely enter the face of unit’s air coil. On horizontal
units, allow adequate room below the unit for a
condensate drain trap and do not locate the unit
above supply piping.
BLOWER CONFIGURABILITY
To change configuration of the LM unit requires
the purchase of a separate Blower panel
Conversion Kit. Please refer to the Spare Parts
List_8733911143 (On website www.fhp-mfg.com)
and the Blower Configurability IM_8733911121.
1
2
3
67
2
8
5
4
For storage If unit stacking is required,
stack units as follows:
Do not stack 6 ton units!
Vertical units: less than 6 tons, no more
than two high.
Horizontals units: less than 6 tons, no more
than three high.
These units are not approved for outdoor
installation; therefore, they must be
installed inside the structure being
conditioned. Do not locate in areas that are
subject to freezing.

6| Return and Discharge Duct Flanges LM Series Heat Pump
LM Series Heat Pump8 733 905 315 (2013/9) Subject to change without prior notice
RETURN AND DISCHARGE DUCT
FLANGES
Return and discharge opening duct flanges are
shipped unfolded. Flanges bend lines are
perforated allowing easy bending using standard
sheet metal pliers or channel locks. (Figure #3)
Figure # 3
MOUNTING VERTICAL UNITS
Vertical units should be mounted level on a
vibration absorbing pad slightly larger than the
base to minimize vibration transmission to the
building structure. It is not necessary to anchor the
unit to the floor. (Figure #4).
Figure # 4
MOUNTING HORIZONTAL UNITS
While horizontal units may be installed on any level
surface strong enough to hold their weight, they
are typically suspended above a ceiling by
threaded rods. The manufacturer recommends
these be attached to the unit corners by hanger
bracket kits. The rods must be securely anchored
to the ceiling. Refer to the hanging bracket
assembly and installation instructions for details.
Plumbing connected to the heat pump must not
come in direct contact with joists, trusses, walls,
etc. Some applications require an attic floor
installation of the horizontal unit. In this case the
unit should be set in a full size secondary drain pan
on top of a vibration absorbing mesh.
The Secondary drain pan prevents possible
condensate overflow or water leakage damage to
the ceiling.
The secondary drain pan is usually placed on a
plywood base isolated from the ceiling joists by
additional layers of vibration absorbing mesh. In
both cases, a 3/4”drain connected to this
secondary pan should be run to an eave at a
location that will be noticeable.
Bend flanges one at a time, using standard
sheet metal pliers or channel locks.
On VT Units Condensate Drain pan is internally
sloped. There is no internal P-Trap.
Horizontal units installed above the ceiling
must conform to all local codes. An auxiliary
drain pan if required by code, should be at
least four inches larger than the bottom of
the heat pump.
VIBRATION
PAD FULL SIZE

Condensate Drain | 7LM Series Heat Pump
8 733 905 315 (2013/9)Revised 09-13
If the unit is located in a crawl space, the bottom
of the unit must be at least 4” above grade to
prevent flooding of the electrical parts during
heavy rains.
CONDENSATE DRAIN
Figure # 5
A drain line must be connected to the heat pump
and pitched away from the unit a minimum of 1/8”
per foot to allow the condensate to flow away from
the unit.
This connection must be in conformance with local
plumbing codes. A trap must be installed in the
condensate line to insure free condensate flow.
A vertical air vent is sometimes required to avoid
air pockets. The length of the trap depends on the
amount of positive or negative pressure on the
drain pan. A second trap must not be included.
DUCT SYSTEM
A supply air outlet collar and return air duct flange
are provided on all units to facilitate duct
connections.
Fold the d uct flange out wards along the perforated
line. Refer to unit Dimensional Drawings for
physical dimensions of the collar and flange.
(Pg#55 through Pg#58)
A flexible connector is recommended for supply
and return air duct connections on metal duct
systems. All metal ducting should be insulated
with a minimum of one inch duct insulation to
avoid heat loss or gain and prevent condensate
forming during the cooling operation. Application
of the unit to uninsulated duct work is not
recommended as the unit’s performance will be
adversely affected.
The factory provided air filter must be removed
when using a filter back return air grill. The factory
filter should be left in place on a free return
system.
If the unit will be installed in a new installation
which includes new duct work, the installation
should be designed using current ASHRAE
procedures for duct sizing. If the unit is to be
connected to existing duct work, a check should
be made to assure that the duct system has the
capacity to handle the air required for the unit
application. If the duct system is too small, larger
duct work should be installed. Check for existing
leaks and repair.
The duct system and all diffusers should be sized
to handle the designed air flow quietly. To
maximize sound attenuation of the unit blower, the
supply and return air plenums should be insulated.
There should be no direct straight air path thru the
return air grille into the heat pump. The return air
inlet to the heat pump must have at least one 90
degree turn away from the space return air grille. If
air noise or excessive air flow are a problem, the
blower speed can be changed to a lower speed to
reduce air flow.
Horizontal (HZ) units must be installed
pitched toward the Condensate Drain
Connection 1/8” per foot.
HZ Heat Pump Drain Pan is not internally
sloped.
Supply air duct and return air duct flanges are
shipped unfolded with unit.
Do not connect discharge ducts directly to
the blower outlet.

8| Piping LM Series Heat Pump
LM Series Heat Pump8 733 905 315 (2013/9) Subject to change without prior notice
PIPING
Supply and return piping must be as large as the
unit connections on the heat pump (larger on long
runs).
LM units are supplied with either a copper or
optional cupro-nickel condenser. Copper is
adequate for ground water that is not high in
mineral content.
In conditions anticipating moderate scale
formation or in brackish water a cupro-nickel heat
exchanger is recommended.
Both the supply and discharge water lines will
sweat if subjected to low water temperature.
These lines should be insulated to prevent damage
from condensation. All manual flow valves used in
the system must be ball valves. Globe and gate
valves must not be used due to high pressure drop
and poor throttling characteristics.
Always check carefully for water leaks and repair
appropriately. Units are equipped with female pipe
thread fittings. Consult Unit Dimensional
Drawings. (Pg#55 through Pg#58)
Flexible hoses should be used between the unit
and the rigid system to avoid possible vibration.
Ball valves should be installed in the supply and
return lines for unit isolation and unit water flow
balancing.
ELECTRICAL
Refer to electrical component box layout.
(Figures #6-8)
Properly sized fuses or HACR circuit breakers must
be installed for branch circuit protection. See unit
nameplate for maximum fuse or breaker size.
The unit is provided with a concentric knock-out
for attaching common trade sizes of conduit, route
power supply wiring through this opening.
Always connect the ground lead to the grounding
lug provided in the control box and power leads to
the line side of compressor contactor as indicated
on the wiring diagram (Figures#25 through #31,
Pg#38 through Pg#47).
Never use flexible hoses of a smaller inside
diameter than that of the fluid connections
on the unit.
Proper testing is recommended to assure the
well water quality is suitable for use with water
source equipment.
Never exceed the recommended water flow
rates, as serious damage or erosion of the
water-to-refrigerant heat exchanger could
occur.
Teflon tape sealer should be used when
connecting water piping connections to the units
to insure against leaks and possible heat
exchanger fouling.
Do not overtighten the connections.
Field wiring must comply with local and
national electric codes.
Power to the unit must be within the
operating voltage range indicated on
the unit nameplate or on the
performance data sheet.
Operation of unit on improper line
voltage or with excessive phase
imbalance will be hazardous to the unit,
constitutes abuse and may void the
warranty.
Units supplied with internal electric heat require
two (2) separate power supplies:
1) Unit compressor
2) Electric Heat, Blower Motor and Control
Circuit.
--------------------------------------------------------------
Refer to the ELECTRIC HEATER PACKAGE
OPTION section and Pg#38 through Pg#47 for
wiring diagrams. See data plate for minimum
circuit ampacities and maximum fuse/breaker
sizing.

Electrical | 9LM Series Heat Pump
8 733 905 315 (2013/9)Revised 09-13
Figure # 6 - Single Phase Unit
Figure # 7 EBox Cover
Figure # 8 Three Phase Unit
[1] Compressor contactor
[2] Emergency Relay (Option)
[3] Second Stage Relay
[4] Hot Gas Reheat Relay (Option)
[5] Cooling Relay
[6] Unit Protection Module (UPM)
[7] Terminal block Low-Voltage
[8] Auxiliary Relay (Option)
[9] Transformer
[10] Capacitor
[11] ECM Interface Board(Option, mounts on E-
Box cover)
[12] Phase Monitor
[13] Fan Status Switch (Option)
[14] Pump Status Switch (Option)
[15] Terminal Block 460V Units (Option)
[16] Comfort Alert Module (Option)
[17] DDC (Option)
[18] LonWorks Card (Option)
[19] Input Expansion Module (Option)
[20] Smart Start Assist (Option)
[21] Ground Lug
4
5
16
3
2
21
6
78
9
110
18
20
11
19
17
4
5
14
13
3
12
15
8
9
7
6
2
21
1

10 | Electrical LM Series Heat Pump
LM Series Heat Pump8 733 905 315 (2013/9) Subject to change without prior notice
Safety Devices and the UPM Controller
Figure # 9
[1] Board Power Indicator
[2] UPM Status LED Indicator
[3] Water Coil Freeze Protection Temperature
Selection [R30]
[4] Air Coil Freeze Protection Temperature
Selection
[5] UPM Board Settings
[6] Water Coil Freeze Connection
[7] Air Coil Freeze Connection
[8] LED Status-Diagnostic Connection
[9] 24VAC Power Input
[10] Compressor Contact Output
[11] High Pressure Switch Connection
[12] Call for Compressor Y1
[13] Low Pressure Switch Connection
[14] 24VAC Power Common
[15] Condensate Overflow Sensor
[16] Dry Contact
[17] UPM Ground Standoff
Each unit is factory provided with a Unit Protection
Module (UPM) that controls the compressor
operation and monitors the safety controls that
protect the unit.
Safety controls include the following:
• High pressure switch located in the refrigerant
discharge line and wired across the HPC
terminals on the UPM
• Low pressure switch located in the unit
refrigerant suction line and wired across
terminals LPC1 and LPC2 on the UPM.
• Water side freeze protection sensor, mounted
close to condensing water coil, monitors
refrigerant temperature between condensing
water coil and thermal expansion valve. If
temperature drops below or remains at freeze
limit trip for 30 seconds, the controller will
shut down the compressor and enter into a
soft lockout condition. The default freeze limit
trip is 30°F, however this can be changed to
15°F by cutting the R30 or Freeze1 resistor
located on top of DIP switch SW1. Refer to
Figure #9, item [3] for resistor location. (Refer
to Figure #10 for sensor location)
Figure # 10
If the unit is being connected to a thermostat
with a malfunction light, this connection is made
at the unit malfunction output or relay. Refer to
Figure #9.
If the thermostat is provided with a malfunction
light powered off of the common (C) side of the
transformer, a jumper between “R” and “COM”
terminal of “ALR” contacts must be made.
1
2
3
4
5
6
7910
11
1213
17
14
15
16
8
If the thermostat is provided with a malfunction
light powered off of the hot (R) side of the
transformer, then the thermostat malfunction
light connection should be connected directly to
the (ALR) contact on the unit’s UPM board.
UPM Board Dry Contacts are Normally Open
(NO)
If unit is employing a fresh water system (no
anti-freeze protection), it is extremely
important to have the Freeze1 R30 resistor
set to 30°F in order to shut down the unit at
the appropriate leaving water temperature
and protect your heat pump from freezing if
a freeze sensor is included.