National Comfort Product 1000 SERIES, Руководство по установке

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When locating the room thermostat, it should be in the natural
circulating path of room air. Avoid locations where the thermo-
stat would be exposed to cold air infiltration; drafts from win-
dows, doors or other openings leading to the outside; exposure
to air currents from warm-or-cold air registers or to exposure
where the natural circulation of the air is cut off, such as behind
doors, above or below mantels, shelves, etc.
Sequence of Operations
5
1. Annually clean the inside of the unit to keep the weep holes
in the base pan and in the fan scrolls open to assure proper
drainage of water from the unit.
2. Keep the condenser coil clean and free of anything that
restricts free air flow. On sea coast applications the con-
denser coil should be washed periodically to remove salt
accumulation.
3. Reduced indoor air flow through a duct system will cause
indoor coil to ice up in cooling. If this condition is allowed
to continue, premature system failure will result. Indoor air
filters should be cleaned and changed regularly.
4. Annually check units mounting to structure to ensure in-
tegrity. Seal between cabinet and/or sleeve for air or water
leakage. Check exposed surfaces for corrosion. Replace
or paint part as required. This maintenance is critical to
prevent stains and damage to exterior surface of building.
5. Inspect refrigerant piping for leaks and suction line insu-
lation. Improper insulation can cause condensate water
damage.
6. Pressure and temperature readings of high and low side
of system should be checked for proper super heat and/or
subcooling. Correct if required.
7. Inspect motor mount, amps to nameplate, hubs for tight-
ness, balance, and rust or corrosion.
8. Inspect wire connection for evidence of arcing, overheating
and deterioration.
Sequence of Operations
for Madison Avenue Option
Step 7 - Maintenance
The compressor crankcase heater will be energized as long as
there is power to the unit. The high pressure switch (HPS) and
low pressure switch (LPS) will be closed as long as refrigerant
pressure in the condensing unit is normal.
Upon a call for cooling as indicated by 24-vac being applied
to low voltage connections C and Y. The delay on Make Tim-
er (DOM) will be energized, but the compressor will not start
until the time period set on DOM is completed. After a few
seconds of full voltage to start the Outdoor Blower Motor (3C),
FSC will modulate the speed of 3C if the probe temperature
on the condensing unit coil is between 70°F and 100°F, so that
operation of 3C will reduce the refrigerant pressure in the
condensing unit and the compressor will have less differential
pressure to start against. After the time period set on DOM is
completed, the compressor contactor (2A) will be energized and
start the compressor (3J) to provide cooling. When the 24-vac is
removed from low voltage connections C and Y, or either HPS
or LPS opens, 2A, 4A, 3C, 3J, DOM, DOB, CR, and FSC will be
de-energized.
If 24-vac power is applied to low voltage connections C and Y
before the time period set on DOB is completed, the sequence
described above will not occur until DOB completes the timing
period.
On a “call for cooling”, the thermostat “makes” circuits R-Y and
R-G. Circuit R-Y energizes the contactor starting the outdoor
fan motor and compressor circuit. R-G energizes the indoor unit
blower relay starting the indoor blower motor.
When the thermostat is satisfied, its contacts open, de-ener-
gizing the contactor and blower relay. Compressor and motors
should stop.