Mitsubishi MT300 User Manual

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52
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For Home Owners
'10 • HM-T-149
Operating mode “Add. heat only”
Intheeventofmalfunctionsthatcausealowindoortemperature,
you can normally activate “Add. heat only” in indoor unit, which
means that heating only occurs with the immersion heater.
Activate the mode by holding in the operating mode button
for 7 seconds.
Notethatthisisonlyatemporarysolution,asheatingwiththe
immersionheaterdoesnotmakeanysavings.
Emergency mode
Emergencymodeisactivatedbysettingtheswitchto“ ”.
Itisusedwhenthecontrolsystemandtherebyoperatingmode
“Add.heatonly”donotfunctionas they should. Emergency
modeisactivatedbysettingswitch(SF1)to“
”.
Thefollowingappliesinemergencymode:
■ Thefrontpanelisnotlitandthecontrolcomputerinindoor
unit is not connected.
■ Outdoor unit is off andonly the circulation pump and
immersion heater in indoor unit are active.
■ Anelectricalstep of4 kWis connected.The immersion
heater is controlled by a separate thermostat (BT30).
■ Theautomaticheatingcontrolsystemisnotoperational,so
manual shunt operation is required. Call installer.
The phenomena mentioned below are not malfunction.
The air conditioning system
sounds as if water is
draining from it.
Soundsofrustlingorgurglingmaybeheardwhentheoperationisstarted,whenthecompressoris
activated/deactivated during operation, or when the operation is stopped. These are the sounds of the
refrigerantowingthroughthesystem.
Soundsofrustlingor
gurgling may be heard from
a stopped indoor unit.
These sounds can be heard when the air conditioning system is performing automatic control.
The air conditioning system
cannot start operating again
immediately after stopping.
Outdoorunitdoesn’trestartduringtherst3minutesafterstoppingoperation.Thisisbecauseacircuit
for protecting the compressor is activated (the fan is operating during this period).
The outdoor unit discharges
water or steam during
heating operation.
Waterorsteamisdischargeduringdefrostingoperationwhichremovesfrostbuiltuponthesurfaceof
the heat exchanger in the outdoor unit in heating mode.
The outdoor unit fan is not
running even when the
system is in operation.
Thefanspeedisautomaticallycontrolledaccordingtotheoutdoorairtemperature.Itmaybestoppedin
high outdoor air temperature in case of heating, and in low outdoor air temperature in case of cooling.
Also, the fan is stopped during defrosting operation.
REQUESTS
The fan will suddenly begin to operate even if it is stopped. Do not insert finger and/or stick.
Hissing sounds are heard
when the operation is
stopped or during defrost
operation.
These sounds are generated when the refrigerant valve inside the air conditioning system is activated.
Dealing with comfort disruption

Mitsubishi MT300 Specifications

General

Brand	Mitsubishi
Model	MT300
Category	Heat Pump
Language	English