McQuay WHR 040, Installation And Maintenance Data

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GLYCOL SOLUTIONS
The system glycol capacity, glycol solution flow rate in gpm,
Test coolant with a clean accurate glycol solution hydrometer
and pressure drop through the cooler may be calculated us-
(similar to that found in service stations) to determine freez-
ing the following formulas and table.
ing point. Then obtain percent glycol from the freezing point
CAPACITY - Capacity is reduced from that with plain
water. To find the reduced value multiply the chiller’s water
system tonnage by the capacity correction factor C to find
the chiller’s capacity in the glycol system.
GPM -To determine gpm (or knowing T (or gpm)
and tons:
Glvcol
,
A T
x G (from table)
PRESSURE DROP -To determine glycol pressure drop
through the cooler, enter the water pressure drop graph
on page 9 at the glycol gpm. Multiply the water pressure
drop found there by P to obtain corrected glycol pressure
drop.
table below.
32°F 1.000
1.000 1.00 1.00
10
0.990 0.994 1.01 1.06
20
0.981 0.988 1.04 1.12
30 4°F 0.974 0.984 1.08 1.18
40 - 1 2 ° F 0.968 0.981 1.13 1.24
50 - 3 3 ° F 0.964 0.980 1.20 1.30
CONDENSER - The use of a glycol solution in the heat
recovery condensers will not affect heat recovery capacity.
PERCENT BY VOLUME
lb
% ETHYLENE GLYCOL BY WEIGHT
1.30
1.25
1.20
100
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