Carrier Aquazone 50HQP 072, Installation, Start-Up And Service Instructions Manual

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16
COOLING TOWER/BOILER APPLICATION
To ensure adequate cooling and heating performance, the cooling
tower and boiler water loop temperature should be maintained be -
tween 50°F and 80°F in the heating mode and 70°F and 110°F in
the cooling mode. In the cooling mode, heat is rejected from the
unit into the water loop. A cooling tower provides evaporative
cooling to the loop fluid, thus maintaining a constant supply tem -
perature to the unit. When utilizing an open cooling tower, chemi -
cal water treatment is mandatory to ensure the water is free of cor -
rosive materials.
A secondary heat exchanger (plate frame between the unit and the
open cooling tower) may also be used. It is imperative that all air
is eliminated from the closed loop side of the heat exchanger to
prevent condenser fouling. In the heating mode, heat is absorbed
from the water loop to the unit. A boiler can be utilized to maintain
the loop within the proper temperature range.
No unit should be connected to the supply or return piping until
the water system has been completely cleaned and flushed to re -
move dirt, piping chips or other foreign material. Supply and re -
turn hoses should be connected together during this process to en -
sure the entire system is properly flushed. After the cleaning and
flushing has taken place the unit may be connected to the water
loop and should have all valves wide open. See Fig. 14.
Fig. 14 — Cooling Tower/Boiler Application