Trane RAUJ-C20, Installation, Operation And Maintenance Manual

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106 SS-SVX11K-EN
W WA AR RN NIIN NG G
L Liiv ve e E Elle eccttrriicca all C Co om mp po on ne en nttss!!
F Fa aiillu urre e tto o ffo ollllo ow w a allll e elle eccttrriicca all ssa affe etty y p prre ecca au uttiio on nss
w wh he en n e ex xp po osse ed d tto o lliiv ve e e elle eccttrriicca all cco om mp po on ne en nttss cco ou ulld d
rre essu ulltt iin n d de ea atth h o orr sse erriio ou uss iin njju urry y..
W Wh he en n iitt iiss n ne ecce essssa arry y tto o w wo orrkk w wiitth h lliiv ve e e elle eccttrriicca all
cco om mp po on ne en nttss,, h ha av ve e a a q qu ua alliiffiie ed d lliicce en nsse ed d e elle eccttrriicciia an n
o orr o otth he err iin nd diiv viid du ua all w wh ho o h ha ass b be ee en n p prro op pe errlly y ttrra aiin ne ed d
iin n h ha an nd dlliin ng g lliiv ve e e elle eccttrriicca all cco om mp po on ne en nttss p pe errffo orrm m
tth he esse e tta asskkss..
4. Turn the 115 volt control circuit switch 1S2 to the
“On” position.
5. Turn the main power disconnect switch or circuit
protector switch for the unit to the “On” position.
W WA AR RN NIIN NG G
R Ro otta attiin ng g C Co om mp po on ne en nttss!!
F Fa aiillu urre e tto o d diisscco on nn ne ecctt p po ow we err b be effo orre e sse errv viicciin ng g cco ou ulld d
rre essu ulltt iin n rro otta attiin ng g cco om mp po on ne en nttss ccu uttttiin ng g a an nd d sslla assh hiin ng g
tte ecch hn niicciia an n w wh hiicch h cco ou ulld d rre essu ulltt iin n d de ea atth h o orr sse erriio ou uss
iin njju urry y..
D Diisscco on nn ne ecctt a allll e elle eccttrriicc p po ow we err,, iin nccllu ud diin ng g rre em mo otte e
d diisscco on nn ne eccttss b be effo orre e sse errv viicciin ng g.. F Fo ollllo ow w p prro op pe err
llo occkko ou utt//tta ag go ou utt p prro occe ed du urre ess tto o e en nssu urre e tth he e p po ow we err
cca an n n no ott b be e iin na ad dv ve errtte en nttlly y e en ne errg giizze ed d..
6. Turn the field provided disconnect switch for the
supply fan to the “On” position and “bump” the
field supplied control circuit switch “On”, (i.e., “On”
then immediately “Off”).
7. If the fan does not start in applications where the
fan control circuit is energized via terminal 7TB5-1
in the RAUJ 115V control circuit, the field power
wiring to the RAUJ unit could be improperly
phased. Phase protection module (1U3) located in
the RAUJ control box interrupts control circuit
power when improperly phased field power is
detected.
8. While the fan is coasting down, check the rotation.
If the fan is rotating backwards, turn the field
provided disconnect switch for the air handler to
the “Off” position and interchange any two of the
main power wires at the fan motor starter or
contactor.
9. After all adjustments have been made, restart the
supply fan and proceed through the following
procedures.
System Airflow Measurement
Much of the systems performance and reliability is
closely associated with, and dependent upon having
the proper airflow supplied both to the space that is
being conditioned and across the evaporator coil.
Measuring Airflow
With the supply fan rotating in the proper direction,
measure the amperage at the supply fan contactor. If
the amperage exceeds the motor nameplate value, the
static pressure is less than design and the airflow is too
high. If the amperage is below the motor nameplate
value, static pressure could be too high and CFM could
be too low. To determine the actual CFM (± 5%);
1. Measure the actual fan RPM
2. Calculate the Theoretical BHP:
BHP = Actual Motor Amps X Motor HP)/
Motor Nameplate Amps
3. Plot this data onto the appropriate Fan Performance
Curve or Performance Table that shipped with the
Air Handling equipment. Where the two points
intersect, read the CFM line.
Use this data to assist in calculating a new fan drive if
the CFM is not at design specifications.
Alternate Method
An alternate method with less accuracy is to measure
the static pressure drop across the evaporator coil. This
can be accomplished by the following steps.
1. Drill a small hole through the unit casing on each
side of the coil.
N NO OT TIIC CE E
C Co oiill D Da am ma ag ge e!!
F Fa aiillu urre e tto o ffo ollllo ow w iin nssttrru uccttiio on nss cco ou ulld d rre essu ulltt iin n cco oiill
d da am ma ag ge e..
W Wh he en n d drriilllliin ng g h ho olle ess iin n tth hiiss a arre ea a,, tta akke e cca arre e tto o a av vo oiid d
d da am ma ag giin ng g cco oiill..
2. Measure the difference between the pressures at
both locations.
3. Plot this value onto the appropriate component
pressure drop curve that shipped with the Air
Handling equipment. Use the data to assist in
calculating a new fan drive if the CFM is not at
design specifications.
4. Plug the holes after the proper CFM has been
established.
After all adjustments have been made, proceed
through the following procedures.
S Stta arrtt--U Up p