Options; Electric Heat; Installation Of Pressure; Regulating Valves - Bosch LM024 Installation, Operation And Maintenance Manual

LM Series Heat Pump

OPTIONS

Electric Heat

Internally mounted supplemental electric heat is
available on select models of the LM series.
Electric heating elements can operate along with
reverse cycle heating as auxiliary heat or in lieu of
mechanical heating (refrigeration heating) as
emergency backup heat.
Availability matrix, including available nominal kW
capacities is shown in Figure #12:
Internal mounted Electric Heat is only available
on top blow vertical cabinets, end blow
horizontal cabinet or on down blow counterflow
cabinets.
Figure 12: Heater Kit Compatibility Table
Heater Model
208V
HK/HP050-1201
HK/HP100-1201
HK/HP150-1201 10.8
HK/HP200-1201 14.4
Note: x = available
INSTALLATION OF PRESSURE

REGULATING VALVES

Pressure regulating valves are used to increase or
decrease water flow through the heat pump in
response to refrigerant pressure. In some cases
more water may be required in heating than in
cooling, or vice versa. With the Envirosaver heat
pumps these valves are not required. However, if
installed, a pair of valves are required for proper
operation, one valve for cooling (direct acting) and
another valve for heating (indirect acting). A
refrigerant tap is provided in the refrigerant line
located between the reversing valve and the water-
to-refrigerant heat exchanger for proper
monitoring of the refrigerant pressures.
The discharge water from the heat pump is not
contaminated in any manner and can be disposed
of in various ways depending on local building
codes (i.e. discharge well, dry well, storm sewer,
drain field, stream or pond, etc.) Most local codes
forbid the use of a sanitary sewer for disposal.
Consult your local building and zoning department
to insure compliance in your area.
Revised 01-14
KW Btu/h
230V 208V 230V
3.6 4.8 12300 16300
7.2 9.6 24600 32700
14.4 36900 49100
19.2 49200 63400
In cases where Electric Heat is not available in
a desired configuration but is needed, contact
your distributor for available Duct Mounted
Electric Heat Package.
Units with internal electric heat must have
2 field power supplies.
Product Series Compatibility
LM024 LM036 LM048
x x
x x
x
SEQUENCE OF OPERATION
(Figure #13 Wire Schematic)
Cooling Mode
Energizing the "O" terminal energizes the unit
reversing valve in the cooling mode. The fan motor
starts when the "G" terminal is energized. Note
that the fan motor will take 30 seconds to ramp up
to operating speed and will run at fan only air flow
as long as there is no call for compressor or heater
operation.
When "Y1" in the unit ("Y" on the thermostat) is
energized the compressor starts and the unit is
now cooling. Solenoid valves or loop pumps are
brought on in conjunction with the compressor.
When the thermostat is satisfied, the compressor
shuts down and the fan ramps down. If the "G"
terminal is still energized (fan operation is on
"continuous" at the thermostat) the fan will ramp
down to fan only air flow in 30 seconds. If the "G"
terminal is de-energized with "Y1" then the fan
ramps down to off in 30 seconds.
OPTIONS | 11
LM060 LM070
x x x
x x x
x x x
x x x
8 733 920 847 (2014/01)