Zehnder Rittling H4C, Инструкция по установке, эксплуатации и обслуживанию

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valve. The valve, in turn, modulates
water flow through the coil to main
the desired temperature.
Maintenance instructions
Coil
Coils may be cleaned by removing
the surrounding enclosure. Brush
the entire finned surface with a soft
bristled brush, brushing parallel to
the fins, taking care not to damage
the fins. Brushing should be followed
by cleaning with a vacuum cleaner. If
fins are damaged during the cleaning
process, a 12 fins per inch fin comb
can be used to straighten the fins.
For a deeper cleaning, spray the
finned surface with a neutral cleaning
solution and rinse thoroughly.
Zehnder Rittling recommends using
neutral pH cleaners. Avoid the use
of strong acids and strong base
cleaners. Thus, cleaners with pH
range from 5 to 11 are suitable for coil
cleaning. This range includes such
over-the-counter cleaners as Simple
Green
®
All Purpose Cleaner, or HVAC
coil cleaners like Nu-Calgon Evap
Pow'r
®.
Strong acidic cleaners (pH of
5 or less) that contain hydrochloric,
sulfuric, nitric or acetic acid are
not recommended for use on
copper-tube, aluminum fin coils.
Presence of these acids will result
in rapid corrosion of the metals.
Strong alkali (base) cleaners (pH
of 11 or more) containing sodium,
potassium or ammonium hydroxide
are not recommended as they will
aggressively corrode aluminum
tubes and fins. Strong ammonium
hydroxide cleaners will also cause
stress corrosion cracking of copper
tubes. Zehnder Rittling recommends
completely rinsing all cleaners from
the coil, including cleaners identified
as no-rinse cleaners. Residual
cleaners may decompose over time
producing low molecular weight,
organic acids that lead to formicary
corrosion.
Failure to maintain a clean
coil surface will result in
reduced airflow and reduced
performance. Clean the coil at
every inspection. Units provided
with the proper type of air
filters or lint screens, replaced
regularly, will require less
frequent coil cleaning.
Coil removal
n
Shut off water to and from unit.
Disconnect lines to and from
coil.
n
Remove coil end cover.
n
Remove the (2) sheet metal
screws fastening condensate
pan to unit.
n
Remove the (4) sheet metal
screws fastening coil to unit
and remove coil.
n
Install new coil in reverse.
Lint screens
These types of filters should be
cleaned on a regular basis. The
time interval between cleaning is
dependent upon the environment
in which the unit is operating and
should be established based
on regular inspection of the lint
screen. Record the time interval
in the maintenance log for future
reference.
Remove unit front panel for
access. Clean screen with soft
brush or vacuum.
Drain
The drain pan and drain (where
applicable) should be checked
during initial start-up and at
the beginning of each cooling
season to ensure that the pan,
drain, trap and line are all clear.
If clogged, steps should be
taken to clear the debris to allow
proper flow of condensate.
General
Each unit on a project will
have its own unique operating
environment and conditions
which dictate a maintenance
schedule for that unit that
may be different from other
equipment on the project. A
formal regular maintenance
schedule and an individual
unit log should be established
and maintained. Following this
schedule will help maximize the
performance and service life of
each unit on the project.
The safety considerations listed
in the front of this manual should
be followed during any service
and maintenance operations.
Operating instructions
The water control units control
room temperature by means of a
field-supplied water flow control
valve that modulates the flow
of hot or chilled water through
the unit coil. Primary air from
the central station air handling
apparatus flows through high
pressure, high velocity ductwork
to the water control induction
unit. The conditioned primary air
flows through the unit plenum
and then passes through a
balancing damper into induction
nozzles. As the primary air
leaves the nozzles, it induces
secondary (room) air through
the unit coil. Depending on the
temperature of the water flowing
through the coil, the secondary
air is cooled or heated. Unit
capacity is controlled either
manually or by a field-supplied
room thermostat modulating
a field-supplied water control
Normal operation
and periodic
maintenance