Mitsubishi FDUA125VNPWVH - (4) Defrost operation

'22 • PAC-SM-412
-
29
-
(ii) Heating
1) Operating conditions
Whentheoutdoorairtemperature(TH2)is13ºCorhighercontinuesfor30secondswhilethecompressorspeedisotherth an
0rps
2) Detail of operation
Af tertheoutdoorfanoperatesat-3speedfor60seconds;thecorrespondingoutdoorheatexchangertemperatureshallimpl e-
mentthefollowingcontrols.
a)Outdoorheatexchangertemperature
=
<
10ºC
Aftertheoutdoorfanspeedrises(up)to1speedfor60seconds;iftheoutdoorheatexchangertemper-
atureislowerthan10ºC,graduallyincreasetheoutdoorfanspeedby1speed.
b)10ºC<Outdoorheatexchangertemperature
=
<
13ºC
Aftertheoutdoorfanspeedmaintainsfor20seconds;iftheoutdoorheatexchangertemperatureis10ºC
-
13ºC,maintainoutdoorfanspeedagain.
c)Outdoorheatexchangertempeature>13ºC
Aftertheoutdoorfanspeeddrops(down)to1speedfor60seconds;iftheoutdoorheatexchangertemper-
atureishigherthan13ºC,graduallyreduceoutdoorfanspeedby1speed.(Lowerlimit2ndspeed)
3) Reset conditions
Wheneitherofthefollowingconditionsissatised
a) The outdoor air temperature (TH2) is 11ºC or lower.
b)Thecompressorspeedis0rps.
(f) Outdoor fan motor protection
If the outdoor fan motor has operated at 75 min
-1
orlowerformorethan30seconds,thecompressorandfanmotorarestopped.
(a)Startingconditions(Defrostoperationcanbestartedonlywhenallofthefollowingconditionsaresatisfied.)
(i)Afterstartofheatingoperation
 Whenitelapsed35minutes(Accumulatedcompressoroperationtime)
(ii)Afterendofdefrostoperation
 Whenitelapsed35minutes(Accumulatedcompressoroperationtime)
(iii)Outdoorheatexchangersensor(TH1)temperature
When the temperature has been below
－
5ºC for 3 minutes continuously
(iv)
Thedierencebetweentheoutdoorairsensortemperatureandtheoutdoorheatexchangersensortemperature(TH2-TH1)
●
The outdoor air temperature
≧
－
2ºC:7ºCorhigher
●
－
15ºC
＜
The outdoor air temperature
＜ －
2ºC:4/15×Theoutdoorairtemperature+7ºCorhigher
●
The outdoor air temperature
≦
－
15ºC:
－
5ºCorhigher
-20
-20 -15 -10 -5 0 5 10
-15
-10
-5
0
Outdoor air temperature (℃)
Outdoor heat exchanger temperature (
℃
)
Defrost operation
start
Defrost operation start temperature
(v)Duringcontinuouscompressoroperation
In addition, when the speedcommand from the indoor control of the indoor unit during heatingoperation has
counted0rps10timesormoreandallconditionsof(i),(ii)aboveandtheoutdoorairtemperatureis3ºC or less
and
thetemperatureforoutdoorheatexchangersensor(TH1)is
－
5ºCorless:62rpsormore,
－
4ºCorless:less
than 62 rps are satisfied, defrost operation is started.
(4) Defrost operation