Quantech QTC3040T, Installation Operation & Maintenance

Page: 184 / 190

QUANTECH
184
FORM QTC3-NM1
ISSUE DATE 08/03/2022
SECTION 10 – MAINTENANCE
PLATE AND FRAME HEAT EXCHANGER
(EVAPORATOR) HEATER
The Plate and Frame Heat Exchanger
(evaporator) heater is 120VAC. Dis-
connecting 120VAC power from the
unit, at or below freezing tempera-
tures, can result in damage to the
evaporator and unit as a result of the
chilled liquid freezing.
OVERALL UNIT INSPECTION
In addition to the checks listed on this page, periodic over-
all inspections of the unit should be accomplished to ensure
proper equipment operation. Items such as loose hardware,
component operation, refrigerant leaks, unusual noises, etc.
should be investigated and corrected immediately.
MICROCHANNEL COIL CLEANING
Regular cleaning is an essential part of maintaining
the integrity and heat transfer properties of heat ex-
changers. Failure to follow cleaning guidelines can re-
sult in heat exchanger damage, including leaks or loss
of performance. The cleaning procedures described in
this document are required to maintain the warranty of
the condenser coils.
Microchannel coils tend to accumulate less dirt inside
the coils than on the surface, which makes them easier
to clean than conventional round tube and fin coils.
The reduced depth and parallel tube layout of mi-
crochannel heat exchangers minimize the restriction
of cleaning water through the heat exchanger. This
provides a shorter and more direct path for cleaning
water to effectively carry away dirt and debris during
regular maintenance. During the cleaning process,
take care to avoid damage to the coils and the pro-
tective coatings. The following care points must be
followed during cleaning:
• DO NOT use high pressure water, such as a pres-
sure washer, to clean the coils. High pressure wa-
ter can damage the fins and the protective coatings
on the coil.
• DO NOT contact the coil with a hard object such
as a hose nozzle, hard vacuum nozzle or any other
tool. Hard objects or tools can cause mechanical
damage to the coil material and protective coat-
ings on the coil.
The required cleaning procedure is different depend -
ing on the type of coil and protective coating supplied
with the coil. This section describes the proper proce-
dures to maintain the integrity of each type of coil.
Cleaning Procedure Required for Standard
and Environment Guard Microchannel Coils
Standard and Environment Guard microchannel coils
must be cleaned following this procedure at least once
per quarter to ensure that the integrity of the coils and
the warranty of the coils are maintained. In environ-
ments where coils become heavily fouled, a monthly
frequency of cleaning is recommended
1. Remove surface debris such as dirt, leaves, in-
sects, or fibers with a vacuum cleaner having a
soft brush attachment. When brushing debris off
the face of the coil a soft bristle brush, not wire,
can also be used. Do not scrape the coil with the
vacuum nozzle, air nozzle, or any other hard tool
2. Rinse the coil with potable tap water. Use a gentle
spray from a spray nozzle with a plastic end. Do
not contact the coil with the hose nozzle. Rinse
the coil by running water through every passage
in the heat exchanger surface until it is clean.
3. It is important to remove and excess water trapped
in the coils immediately after the final water rinse.
The condenser fans on the chiller can be run af-
ter the final water rinse to properly dry the coils.
Any excess water can also be removed by blow-
ing air through the coils with a hand held blower
or vacuum.
Cleaning Procedure for Environment Guard
Premium Microchannel Coils
Environment Guard Premium microchannel coils
must be cleaned following this procedure at least once
quarterly to ensure that the integrity of the coils and
the warranty of the coils are maintained. In environ-
ments where there are high levels of pollution or cor-
rosive elements a monthly cleaning procedure using
steps 1, 2 and 7 below is recommended in addition to
the quarterly cleaning using steps 1-8: