Dodge Sprinter 2006 Manual page 2035

VA
Wh en t h e ou t side a ir con t a in s sm oke, odor s, h igh
h u m idit y, or if r a pid coolin g is desir ed, in t er ior a ir
ca n by r ecir cu la t ed by select in g t h e Recir cu la t ion
Mode wit h t h e m ode con t r ol kn ob. Th e m ode con t r ol
kn ob oper a t es t h e r ecir cu la t ion door t h r ou gh u se of a
va cu u m a ct u a t or. Wh en t h e Recir cu la t ion Mode is
select ed, t h e r ecir cu la t ion door is closed t o pr even t
ou t side a ir fr om en t er in g t h e pa ssen ger com pa r t -
m en t .
To m a in t a in m in im u m eva por a t or t em per a t u r e a n d
pr even t eva por a t or fr eezin g, a n eva por a t or t em per a -
t u r e sen sor is u sed.
Th e A/C syst em is design ed for t h e u se of n on -CF C,
R-134a r efr iger a n t on ly a n d u ses a n expa n sion va lve
t o m et er r efr iger a n t flow t o t h e eva por a t or.
DI AGN OSI S AN D T EST I N G
A / C PERFORMANCE
Th e A/C syst em is design ed t o pr ovide t h e pa ssen -
ger com pa r t m en t wit h low t em per a t u r e a n d low
h u m idit y a ir. Th e A/C eva por a t or, loca t ed in t h e
H VAC h ou sin g is cooled t o t em per a t u r es n ea r t h e
fr eezin g poin t . As wa r m da m p a ir pa sses over t h e
fin s of t h e A/C eva por a t or, t h e a ir t r a n sfer s it s h ea t
t o t h e r efr iger a n t in t h e eva por a t or coils a n d t h e
m oist u r e in t h e a ir con den ses on t h e eva por a t or fin s.
Du r in g per iods of h igh h ea t a n d h u m idit y, a n A/C
syst em will be m or e effect ive in t h e Recir cu la t ion
m ode (m a x-A/C). Wit h t h e syst em in t h e Recir cu la -
t ion m ode, on ly a ir fr om t h e pa ssen ger com pa r t m en t
pa sses t h r ou gh t h e A/C eva por a t or. As t h e pa ssen ger
com pa r t m en t a ir deh u m idifies, t h e A/C syst em per-
for m a n ce levels r ise.
H u m idit y h a s a n im por t a n t bea r in g on t h e t em per-
a t u r e of t h e a ir deliver ed t o t h e in t er ior of t h e veh i-
cle. It is im por t a n t t o u n der st a n d t h e effect t h a t
h u m idit y h a s on t h e per for m a n ce of t h e A/C syst em .
Wh en h u m idit y is h igh , t h e A/C eva por a t or h a s t o
per for m a dou ble du t y. It m u st lower t h e a ir t em per-
a t u r e, a n d it m u st lower t h e t em per a t u r e of t h e
m oist u r e in t h e a ir t h a t con den ses on t h e eva por a t or
fin s. Con den sin g t h e m oist u r e in t h e a ir t r a n sfer s
h ea t en er gy in t o t h e eva por a t or fin s a n d coils. Th is
r edu ces t h e a m ou n t of h ea t t h e A/C eva por a t or ca n
a bsor b fr om t h e a ir. H igh h u m idit y gr ea t ly r edu ces
t h e a bilit y of t h e A/C eva por a t or t o lower t h e t em per-
a t u r e of t h e a ir.
H owever, eva por a t or ca pa cit y u sed t o r edu ce t h e
a m ou n t of m oist u r e in t h e a ir is n ot wa st ed. Wr in g-
in g som e of t h e m oist u r e ou t of t h e a ir en t er in g t h e
veh icle a dds t o t h e com for t of t h e pa ssen ger s.
Alt h ou gh , a n own er m a y expect t oo m u ch fr om t h eir
A/C syst em on h u m id da ys. A per for m a n ce t est is t h e
best wa y t o det er m in e wh et h er t h e syst em is per-
for m in g u p t o design st a n da r ds. Th is t est a lso pr o-
vides va lu a ble clu es a s t o t h e possible ca u se of
HEA TING & AIR CONDITIONING 24 - 3
t r ou ble wit h t h e A/C syst em . Th e a m bien t a ir t em -
per a t u r e in t h e loca t ion wh er e t h e veh icle will be
t est ed m u st be a m in im u m of 21° C (70° F ) for t h is
t est .
A / C PERFORMANCE TEST
WARNING: Refer to the applicable warnings and
cautions for this system before performing the fol-
lowing operation (Refer to 24 - HEATING & AIR
CONDITIONING/PLUMBING - WARNINGS) and (Refer
to 24 - HEATING & AIR CONDITIONING/PLUMBING -
CAUTIONS). Failure to follow the warnings and cau-
tions could result in possible personal injury or
death.
NOTE: Very specific instructions and conditions
pertain to this procedure which are significantly dif-
ferent than procedures used in other vehicle appli-
cations. Follow each step in the order they are
presented. Do not skip steps or change conditions
from those stated or results will be adversely
affected and invalid.
NOTE: When connecting the service equipment
coupling to the line fitting, verify that the valve of
the coupling is fully closed. This will reduce the
amount of effort required to make the connection.
(1) Ch eck for dia gn ost ic t r ou ble codes u sin g a
DRBIII sca n t ool. If n o DTCs a r e fou n d in t h e
en gin e con t r ol m odu le (E CM), go t o St ep 2. If a n y
DTCs a r e fou n d, r epa ir a s r equ ir ed, t h en pr oceed t o
St ep 2.
(2) P la ce t h e veh icle in t h e sh a de a n d oper a t e t h e
h ea t in g-A/C syst em u n der t h e followin g con dit ion s.
• E n gin e a t idle a t oper a t in g t em per a t u r e
• All door s or win dows open
• Tr a n sa xle in Neu t r a l
• All A/C du ct lou ver s open
• A/C-h ea t er con t r ols set t o fr esh a ir (NOT Recir-
cu la t e), fu ll cool, pa n el m ode, h igh blower a n d wit h
A/C com pr essor en ga ged.
NOTE: The A/C compressor clutch is de-energized
under any of the following conditions:
• Restricted compressor (thermal fuse in the pul-
ley)
• Low pressure in the system
• Low evaporator temperature
• Hard acceleration (WOT)
• High coolant temperatures
(3) In ser t a t h er m om et er in t h e dr iver side cen t er
pa n el a ir ou t let a n d oper a t e t h e A/C syst em u n t il t h e
t h er m om et er t em per a t u r e st a bilizes.