Mammoth V-Cube - Manual (Page 29)

air in order to avoid unexpected high head pres-
sure and poor cooling/heating performance.
f. A flow balancing valve in the return water line to
set the required flow rate.
g. A flow measuring valve or pressure gauge/con-
nections in the return water line to measure the
required flow rate.
h. A two-way motorized on/off water shut-off valve
to isolate water flowing through both the econo-
mizer coil (if equipped) and water-to-refrigerant
condenser for conservation when the unit is off.
The motorized water valve must open 90 seconds
prior to compressor start-up and remain open
five seconds after the compressor is shut off.
i. A relief valve in the water supply or inlet line if
the maximum pressure of components is less
than the water supply pressure to prevent dam-
age, injury or death due to instantaneous release
of high pressure water.
4. WCC should not be connected to the incoming sup-
ply and return piping until the water supply system
has been cleaned and flushed completely. After the
cleaning and flushing has taken place, the initial con-
nection should have all valves wide open in prepara-
tion for the water system flushing.
5. Automatic flow controlled devices must not be in-
stalled prior to system cleaning and flushing.
Cleaning and Flushing
1. Prior to first operation of the WCC, the water circula-
tion system must be cleaned and flushed of all con-
struction dirt and debris by the Installing Contractor.
2. Short circuit connect the incoming supply line to the
outgoing return line, prior to the factory installed
piping at each connection point, before flushing to
prevent the introduction of dirt into the unit from the
supply line completed on site. This will prevent the
introduction of dirt into the unit.
3. Fill the system at the city water makeup connection
with all air vents open. After filling, close all air vents.
4. Start the main circulator with the pressure reducing
valve open. Check vents in sequence to bleed off any
trapped air to provide circulation through all compo-
nents of the system.
5. While circulating water, check and repair any leaks
in the piping. Drains at the lowest point(s) in the sys-
tem should be opened for the initial flush and blow
down, making sure city water fill valves are set to
make up water at the same rate. Check the pressure
gauge at the pump suction and manually adjust the
makeup to hold the same positive steady pressure
both before and after opening the drain valves. Flush
should continue for at least two hours or longer until
clean drain water is visible.
6. Shut off the circulator pump and open all drains and
vents to completely drain down the system. Short
circuited supply and return lines coming to the unit
should now be removed and supply and return lines
connected to the unit supply and return connections.
Do not use sealers at the swivel flare connections of
the hose(s).
7. Install any automatic flow controlled devices that
were removed for flushing.
8. Refill the system with clean water. Test the water
using litmus paper for acidity, and treat as required
to leave the water slightly alkaline (pH 7.5 to 8.5).
The specified percentage of antifreeze may also be
added at this time. Use commercial grade antifreeze
designed for HVAC systems only. Do not use auto-
motive grade antifreeze.
9. Once the system has been filled with clean water and
antifreeze (if used), precaution should be taken to
protect the system for dirty water conditions. Dirty
water will result in system wide degradation of per-
formance and solids may clog valves, strainers, flow
regulators, etc. Additionally, the heat exchangers
may become clogged which reduces compressor ser-
vice life or causes premature failure.
10. Start the circulation pumps. After full flow has been
established through all components, air vented, lines
checked for leaks and loop temperatures stabilized,
the WCC will be ready for check, start-up and water
a. balancing.
General Maintenance
Recording of performance measurements of volts, amps,
and water temperature difference (both heating and cool-
ing) is recommended. A comparison of logged data with
start-up and other annual data is useful as an indicator of
general equipment condition.
Periodic lockouts almost always are caused by air or water
problems. The lockout (shut-down) of the unit is a normal
protective result. Check for dirt in the water system, water
flow rates, water temperatures, airflow rates (may be dirty
filters), and air temperatures. If the lockout occurs in the
morning following a return from the night setback, enter-
ing air below machine limits may be the cause.
Water treatment is important for proper condenser opera-
tion. More frequent cleaning will be necessary if water is
not properly treated. For water treatment instruction, con-
sult your local water treatment specialist.
!
WARNING
To prevent injury or death due to instantaneous release of
high pressure water, provide relief valves on system water
piping. This will also help prevent water pump damage or
stoppage due to excessive system pressure.
VCES-V-CUBE-IOM-1A 29