AAON LZ Series, Installation Operation & Maintenance

Page: 67 / 104

67
ambient temperature is below 32°F, the
condenser pump will not operate. As the
ambient temperature increases, the condenser
pump will activate at 35°F. As the ambient
temperature decreases, the condenser pump
will deactivate at 32°F. This dead band
prevents the condenser pump from cycling
too much. Below 32°F, the unit operates as
an air-cooled condenser. An optional sump
heater
operates when the ambient
temperature is below 40°F to prevent the
sump from freezing and offers freeze
protection to 0°F.
Pump Maintenance
Cleaning - Remove oil, dust, water, and
chemicals from exterior of motor and pump.
Keep motor air inlet and outlet open. Blow
out interior of open motors with clean
compressed air at low pressure.
Labeled Motors
- It is imperative for repair of
a motor with Underwriters’ Laboratories
label that original clearances be held; that all
plugs, screws, other hardware be fastened
securely, and that parts replacements be exact
duplicates or approved equals. Violation of
any of the above invalidates Underwriters’
Label.
Fan Motor Maintenance
Same as pump maintenance.
Access Doors
If scale deposits or water is found around the
access doors, adjust door for tightness.
Adjust as necessary until leaking stops when
door is closed.
The evaporative condenser doors have an
adjustable fit design. A good seal and fit are
key to avoid leaks. A leak inspection is
recommended during installation and every
six (6) months thereafter. If a leak is found,
use the following steps to adjust the fit of the
door. This process will require at least two (2)
people.
1. Identify and locate the leak(s).
2. Make sure the evaporative condenser
is not running while working on this
process.
3. Open the door and check for damage
to the seal or the frame.as well as the
engagement of the door seal with the
frame.
4. Replace the seal if damage is found.
5. Check to see if this fixed the issue.
6. If the issue persists, the next step is to
check the fit of the door.
7. Disengage the closing mechanism of
the door that has a leak.
8. One person must hold the door, while
the other slowly loosens the four (4)
bolts on the two (2) hinges connecting
the door to the hinge.
Figure 36 – Evaporative condenser access
door
9. Adjust the door as needed to create a
good seal all around the door.
10. Tighten the bolts to secure the door in
place.
11. Run the evaporative condenser and
check to make sure the issue has been
solved.
12. Repeat as needed.
LOOSEN
THESE BOLTS