OMEGA-VSHYe.F-IOM-2108
7
8. Secure risers to building structure as per engineer-
ing design specifications. Do not allow the risers to be
supported by the cabinets. Field supplied riser compen-
sators are required if the temperature range of the sys-
tem exceeds the expansion and contraction limit.
9. Using industry accepted soldering and brazing
standards and materials to solder or braze the riser
joints.
10. Connect supply ducts and discharge grilles.
11. Connect all ERV ducts to their corresponding con-
nections.
RISER LOOP
Servicing
To enable system flushing, servicing and balancing of
supply and return risers the following field supplied com-
ponents are required: shut
-
off valves, drain tees and
drain valves, and flow measuring devices. Refer to the
job site engineering design specifications and building
drawings for more detailed information.
Flushing & Cleaning
Once the riser system is complete the riser system must
be flushed, cleaned and re
-
filled and chemically treated.
Do not connect chassis to the water circulating system
when flushing is being conducted to prevent debris and
fouling of the water side components of the chassis (i.e.
auto balancing valve, auto shut
-
off valve, coaxial coil).
Do not flush and clean riser system with
chassis units connected. Do not allow the
flushing and cleansing solutions to flow in
the chassis water coil. Damage to water
components may occur.
Supply and return pipes must be interconnected, at a
minimum in the top and bottom units of each riser, with
factory supplied hoses to properly flush system and en-
sure adequate elimination of foreign material and clean-
ing of riser system.
1. Use only clean water to fill water circulation system.
Fill the water circulating system at the municipal water
makeup connection with all air vents opened.
2. After air vents have been sequentially closed and riser
system is primed begin water circulation of the system to
purge remaining trapped air bubbles.
3. Shut off the circulating pump and open all the drains
and vents to completely drain the system.
4. The riser system should be cleaned after the initial
flush and flushed a second time to adequately rinse the
riser system of cleaning solution.
Chassis installation is permitted once the riser system is
thoroughly flushed, cleaned, and water loop is chemical-
ly treated and commissioned by the riser treatment com-
pany and contractor.
RISER SYSTEM LOOP TEMPERATURE
Correct riser system loop temperature settings are im-
portant for optimal unit operation. Temperatures outside
of the recommended range will affect overall unit operat-
ing performance (capacity and efficiency), long term
reliability and sound performance.
Cooling Season
In cooling mode recommended riser loop temperatures
should be maintained between 90
o
F to 115
o
F. Higher
riser loop temperatures reduce unit cooling capacity and
efficiency, and increase sound levels. Lower riser loop
temperatures will increase unit operating efficiency.
Operation of riser loop temperatures above 120
o
F EWT
is not permitted. Refer to Table 2: Unit Operation Limits.
Heating Season
In heating mode riser loop temperatures should be
maintained between 90
o
F to 115
o
F for standard range
operation. Do not set loop temperatures above 120
o
F.
Operating Limits
Design limits can not be combined. Combining maxi-
mum or minimum limits is not allowed. This could ex-
ceed the operation and design limits of the unit.
For example: It is not allowed to combine maximum en-
tering air temperature (EAT) limits with maximum enter-
ing fluid temperature (EFT) limits.
Table 2: Unit Operation Limits
Heating
DB
WB
DB
Std. Entering Air Temperature (EAT)
75
o
F
63
o
F
68
o
F
Min. Entering Air Temperature (EAT)
65
o
F
55
o
F
50
o
F
Max. Entering Air Temperature (EAT)
85
o
F
71
o
F
85
o
F
Cooling
Heating
Std. Entering Water Temperature (EWT)
85
o
F
105
o
F
Min. Entering Water Temperature (EWT)
50
o
F
90
o
F
Max. Entering Water Temperature (EWT)
120
o
F
120
o
F
Cooling
Air Limits
Standard Range
Fluid Limits
Min. CFM/Ton
300
Min. GPM/Ton
2
Design CFM/Ton
400
Design GPM/Ton
3
Max. CFM/Ton
450
Max. GPM/Ton
4
Fluid GPM Limits
CFM Limits
