Daikin Maverick I MPSA07D, Руководство по установке и обслуживанию

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IM 971-3 • MAVERICK I 8 www.DaikinApplied.com
Mechanical Installation
Ductwork
WARNING
Never connect return ductwork to any other heat producing device such as
fireplace insert, stove, etc. Unauthorized use of such devices may result
in fire, carbon monoxide poisoning, explosion, personal injury, property
damage or death.
The installing contractor should fabricate ductwork in
accordance with local codes. Use industry manuals as a
guide when sizing and designing the duct system. Contact
Air Conditioning Contractors of America , 1513 16th St. N.W.,
Washington, D.C. 20036.
Place the unit as close to the conditioned space as possible
allowing clearances as indicated. Run ducts as directly as
possible to supply and return outlets. Use of non-flammable
weatherproof flexible connectors on both supply and
return connections at unit to reduce noise transmission is
recommended.
On ductwork exposed to outside temperature and humidity,
use a minimum of 2" of insulation and a vapor barrier.
Distribution system in attic, furred space or crawl space
should be insulated with at least 2" of insulation. 1/2" to 1"
thick insulation is usually sufficient for ductwork inside the air
conditioned space.
Provide balancing dampers for each branch duct in the supply
system. Properly support ductwork from the structure.
IMPORTANT: In the event that the return air ducts must be run
through an “unconfined” space containing other fuel burning
equipment, it is imperative that the user be informed against
future changes in construction which might change this to a
“confined space.” Also, caution the user against any future
installation of additional equipment (such as power ventilators),
within the existing unconfined and/or confined space which
might create a negative pressure within the vicinity of other
solid, liquid, or gas fueled units.
Return Air
WARNING
Never allow products of combustion or the flue products to enter the return
air ductwork, or the circulating air supply. All return ductwork must be
adequately sealed and secured to the furnace with sheet metal screws and
joints must be taped. All other duct joints must be secured with approved
connections and sealed airtight.
Failure to prevent products of combustion from being circulated into the
living space can create potentially hazardous conditions, including carbon
monoxide poisoning that could result in personal injury or death.
HGRH System
The HGRH system controls both cooling and humidity loads.
In addition to two stages of cooling, the unit includes two
stages of reheat. A temperature sensor or thermostat relates
a low cooling demand (y1) or high cooling demand (y2) to the
RTU-C. A separate humidity sensor sends the actual indoor
relative humidity to the RTU-C via a 0-10 VDC signal. The
RTU-C considers a relative humidity level 2%-5% above the
humidity setpoint as a “low humidity demand” (H1). The RTU-C
considers a relative humidity level greater than 5% above
the humidity setpoint as a “high humidity demand” (H2). The
RTU-C determines the unit mode of operation based on the
y1, y2, H1 and H2 (Table 1). Low reheat is only initiated when
there is a humidity call (H1 or H2) and no cooling call (y1 or
y2). In this mode the unit provides essentially “neutral air”
(supply air is 1ºF and -5ºF of return air temperature).
High reheat is only used when there is a high humidity demand
(H2) with a low cooling demand (y1). See RTU-C I&O manual
for reheat unit setup and for thermostat/sensor combinations.
Humidity Sensor
An indoor relative humidity sensor (not included with the unit)
is required for reheat operation.
Refrigerant Solenoid Valves
The reheat refrigerant system is part of System 1 only. Three
refrigerant solenoid valves (discharge, liquid and reheat) are
used to change operation from Cooling Mode to Reheat Mode.
The Discharge Solenoid Valve (DSV) is located in the outdoor
section (front side of unit) and is a normally Closed (n.C.)
valve. The Liquid Solenoid Valve (LSV) is located in the liquid
line in the blower section and is a normally Open (n.O.) valve.
The Reheat Solenoid Valve (RSV) is near the bottom of the
reheat coil (between the evaporator coil and the blower) and is
normally open.
Operation
During the Cooling mode the RSV is the only valve energized
(closed position), LSV is open, DSV is closed. The refrigeration
cycle is standard cooling, reheat coil is bypassed. System
2 operates during High Cooling or High Reheat modes but
is not part of the reheat circuit (always operates in standard
cooling). During Low Reheat or High Retreat modes the LSV is
energized (closed position), DSV is energized (open position),
RHV is open. Some hot gas bypasses the condenser coil and
creates a warm two phase mix that enters the reheat coil.
See Table A for Modes of Operation including compressor
operation, fan speed, thermostat/humidistat calls for each
mode. See Blower VFD