Lennox LHT Series Information

Service Literature
WARNING
To prevent serious injury or death:
1-
Lock-out/tag-out before performing maintenance.
2-
If system power is required (e.g., smoke detector main­
tenance), disable power to blower, remove fan belt
where applicable, and ensure all controllers and ther­
mostats are set to the "OFF" position before
performing maintenance.
3-
Always keep hands, hair, clothing, jewelry, tools, etc.,
away from moving part
WARNING
Improper installation, adjustment, alteration, service
or maintenance can cause property damage, person­
al injury or loss of life. Installation and service must
be performed by a licensed professional HVAC in­
staller or equivalent, service agency, or the gas sup­
plier
The LHT commercial heat pump is available in 6.5, 7.5, 8.5,
10 and 12.5 ton capacities. The refrigerant systems utilize
two compressors, two reversing valves, two accumulators,
and other parts common to a heat pump. Electric heat oper­
ates in single or multiple stages depending on the kW input
size. 7.5kW through 60kW heat sections are available for
the LHT heat pump.
LHT078-150 units are equipped with variable-volume, di­
rect drive blowers. These units will provide supply air at
lower speeds when cooling demand is low and increase to
higher speeds when cooling demand is high. Refer to Sup­
ply Air Start-Up sections.
LHT units are designed to accept any of several different
energy management thermostat control systems with mini­
mum field wiring.
Information contained in this manual is intended for use by
qualified service technicians only. All specifications are
subject to change. Procedures outlined in this manual are
presented as a recommendation only and do not super­
sede or replace local or state codes.
If the unit must be lifted for service, rig unit by attaching four
cables to the holes located in the unit base rail (two holes at
each corner). Refer to the installation instructions for the
proper rigging technique.
100087
LHT HEAT PUMP SERIES
s.
CAUTION
As with any mechanical equipment, contact with
sharp sheet metal edges can result in personal in­
jury. Take care while handling this equipment and
wear gloves and protective clothing.
Electric shock hazard. Can cause injury
or death. Before attempting to perform
any service or maintenance, turn the
electrical power to unit OFF at discon­
nect switch(es). Unit may have multiple
power supplies.
Table of Contents
Options / Accessories
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Blower Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Electrical \ Electric Heat Data
I Unit Components
II Placement and Installation
III Start Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
IV System Service Checks
V Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
VI Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
VII Wiring Diagrams
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LHT
6.5 / 7.5 / 8.5 /10 / 12.5
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