Lennox 14HPX Unit Information page 13

E − High Pressure Switch (S4)
IMPORTANT
Pressure switch settings for R−410A refrigerant will
be significantly higher than units with R−410A.
An auto-reset, single-pole/single-throw high pressure switch
is located in the liquid line. This switch shuts off the compres-
sor when liquid line pressure rises above the factory setting.
The switch is normally closed and is permanently adjusted to
trip (open) at 590 + 10 psi. See Pressure Switch Circuit in
the Defrost Control description.
F − Low Pressure Switch (S87) (option)
An auto-reset, single-pole/single-throw low pressure
switch is located in the suction line. This switch shuts off the
compressor when suction pressure drops below the facto-
ry setting. The switch is closed during normal operating
pressure conditions and is permanently adjusted to trip
(open) at 25 + 5 psi. The switch automatically resets when
suction line pressure rises above 40 + 5 psi. Under certain
conditions the low pressure switch is ignored. See Pres-
sure Switch Circuit in the Defrost Control description.
G − Loss of Charge Switch (S24) (option)
The loss of charge switch is NC, auto re−set and located on
the suction line of the compressor. The switch opens when
suction line pressure exceeds the factory setting of 25 + 5
psig and shuts down the compressor. The switch closes at
55 psig + 5.
H − Start Kit (option)
The start kit consist of a potential relay K31 and start capac-
itor C7. The potential relay controls the operation of the
starting circuit. The relay is normally closed when contactor
K1 is de−energized. When K1 is energized, the compressor
immediately begins start up. K31 remains closed during
compressor start up and capacitor C7 remains in the cir-
cuit. When compressor reaches approximately 75% of its
speed, K31 is energized. When K31 energizes, the con-
tacts open and start capacitor C7 is taken out of the circuit.
10N46 − Refrigerant Analysis
10N45 − Acid Test Tubes
10N44 − Moisture Test Tubes
74N40 − Easy Oil Test Tubes
74N39 − Acid Test Kit
Acid and Moisture Test Kits
KIT
Checkmate−RT700
Checkmate−RT750A (three pack)
Checkmate − RT751 Tubes (three
pack)
Checkmate − RT752C Tubes (three
pack)
Sporian One Shot − TA−1
I − Drier
A filter drier designed for all 14HPX model units is factory
installed in the liquid line. The filter drier is designed to re-
move moisture and foreign matter, which can lead to com-
pressor failure.
Moisture and / or Acid Check
Because POE oils absorb moisture, the dryness of the
system must be verified any time the refrigerant sys-
tem is exposed to open air. A compressor oil sample
must be taken to determine if excessive moisture has been
introduced to the oil. Table 3 lists kits available from Lennox
to check POE oils.
If oil sample taken from a system that has been exposed to
open air does not test in the dry color range, the filter drier
MUST be replace.
Replacement filter drier MUST be approved for
HFC−410A refrigerant and POE application.
It is recommended that a liquid line filter drier be replaced
when the pressure drop across the filter drier is greater
than 4 psig. To safeguard against moisture entering the
system follow the steps in section III − sub section
E − "Evacuating the System" when replacing the drier.
J − Crankcase Heater (HR1) & Thermostat
(S40)
Crankcase heater HR1 and thermostat S40 are standard
on 14HPX−036, −042, −048 and −060 units and an option for
the other sizes. HR1 is a 40 watt heater that prevents liquid
from accumulating in the compressor. HR1 is controlled by
thermostat S40 located in the liquid line. When liquid line
temperature drops below 50° F, S40 closes energizing
HR1. S40 will open once liquid line temperature reaches
70°, de−energizing HR1.
TABLE 3
CONTENTS
2 − 3 years @ room temperature. 3+
years refrigerated
6 − 12 months @ room temperature. 2
years refrigerated
2 − 3 years @ room temperature. 3+
years refrigerated
Page 13
IMPORTANT
Foreign Matter Check
TUBE SHELF LIFE