TM 1-1510-225-10 2-129 accumulator.    A  reservoir,  located  just  inboard  of  the left nacelle and forward of the main spar, has a lid with a dipstick attached marked  FLUID TEMP 0 °F, 50  ° F, l00  ° F.    Add  MIL-H-5606  hydraulic  fluid  (consumable materials list) as required to fill the system, corrected for temperature. 2-93.  INFLATING TIRES. Inflate  nose  wheel  tires  to  a  pressure  between 55 and  60 psi.    Inflate  main  wheel  tires  to  a  pressure between 94 and 98 psi for standard tires or 60 and 64 psi for high flotation tires. 2-94.  SERVICING THE CHEMICAL AND ELECTRICAL TOILET. The   toilet   should   be   serviced   during   routine ground   maintenance   of   the   aircraft   following   every usage.        The    waste    storage    container    should    be removed, emptied, its disposable plastic liner replaced, and the container replaced in the toilet cabinet.  Toilet paper, waste container plastic liners, and dry chemical deodorant  packets   should  also  be  re-supplied  within the toilet cabinet as needed. 2-95.  SERVICING THE AIR CONDITIONING SYSTEM. Servicing the air conditioning system consists of checking and maintaining the correct refrigerant level, compressor    oil    level,    belt    tension    and    condition, system    leak    detection,    and    replacement    of    the evaporator air filters.  It is imperative that only qualified refrigerant system technicians accomplish maintenance of the air conditioning system, except for filter replacement. 2-96.  ANTI-ICING,    DEICING,     AND    DEFROSTING TREATMENT. NOTE Do not apply anti-icing, deicing, and defrosting fluid to exposed aircraft surfaces    if    snow    is    expected.        Melting snow   will   dilute   the   defrosting   fluid   and form   a   slush   mixture   that   will   freeze   in place and become difficult to remove. Use  undiluted  anti-icing,  deicing,  and  defrosting fluid (MIL-A -8243)     to     treat     aircraft     surfaces     for protection   against   freezing   rain   and   frost.      Spray aircraft   surface   sufficiently   to   wet   area,   but   without excessive drainage.  A fine spray is recommended to prevent waste. Use  diluted,  hot  fluid  as  follows  to  remove  ice accumulations: 1.   Remove  frost  or  ice  accumulations  from aircraft  surfaces  by  spraying  with  diluted anti-icing,    deicing,    and    defrosting    fluid mixed in accordance with Table 2-18. 2.   Spray  diluted,  hot  fluid  in  a  solid  stream (not over 15 gallons per minute).   Thoroughly  saturate  aircraft  surface  and remove    loose    ice.        Keep    a    sufficient quantity   of   diluted,   hot   fluid   on   aircraft surface  coated  with  ice,  to  prevent  liquid layer   from   freezing.      Diluted,   hot   fluid should be sprayed at a high pressure, but not exceeding 300 psi. 3.   When facilities for heating are not available  and  it  is  deemed  necessary  to remove   ice   accumulations   from   aircraft surfaces, undiluted defrosting fluid may be used.    Spray  undiluted  defrosting  fluid  at 15-minute   intervals   to   assure   complete coverage.    Removal  of  ice  accumulations using undiluted defrosting fluid is expensive and slow. If    tires    are    frozen    to    ground,    use    undiluted defrosting  fluid  to  melt  ice  around  tire.    Move  aircraft as soon as tires are free. 2-97.  APPLICATION OF EXTERNAL POWER. CAUTION Before  connecting  the  power  cables  from the  external  power  source  to  the  aircraft, ensure  that  the  GPU  is  not  touching  the aircraft  at  any  point.    Due  to  the  voltage drop in the cables, the two ground systems will be of different potentials.  Should they come in contact while the GPU is operating, arcing could occur.  Turn off all external power while connecting the power cable  to,  or  removing  it  from,  the  external power  supply  receptacle.    Be  certain  that polarity of the external power source is the same   as   that   of   the   aircraft   before   it   is connected.      Minimum   GPU   requirements are:        300-amperes,    28    Vdc    continuous output. An   external   power   source   is   often   needed   to supply the electric  current required to properly ground service    the    aircraft    electrical    equipment    and    to facilitate starting the aircraft's engines.  An external dc power  receptacle  is  installed  on  the  underside  of  the right wing, just outboard of the engine nacelle.