Water Connections - Trane Flex II Series Installation Operation & Maintenance

7

WATER CONNECTIONS

7.1 EVAPORATOR
The connection tubes have to be supported adequately in order that their weight does not damage the plant. The
following parts have to be installed on the water circuit of the evaporator:
•
Two pressure gauges of adequate scale (in and out of the unit)
•
Two shock-absorbing joints (in and out of the unit)
•
One shut off valve (normal one in input)
•
One setting valve (in output)
•
Two thermometers (in and out)
•
One circulation pump
•
One safety valve on the water buffer
•
One automatic air vent valve
•
One expansion tank
•
An inlet filter placed as near as possible to the evaporator flange
•
One flow switch
The above-mentioned installation indications represent necessary conditions for the guarantee to be valid.
Trane is at your disposal to examine any different requirements, which have to be approved before starting up the
chiller.
It is necessary that the water flow rate to the unit is compatible with the evaporator one. It is also necessary that the
water flow rate is kept uniform while the unit is running: it is suggested to use always a pump system dedicated to the
unit and independent from the remaining part of the plant.
Before stalling units with temperature around 0°C please evacuate the exchanger with compressed air in order to
avoid breakings due to ice.
If the unit is installed in order to replace another, the entire hydraulic system must be emptied and cleaned before
the new unit is installed. Regular tests and proper chemical treatment of water are recommended before starting up
the new unit.
In the event that glycol is added to the hydraulic system as anti-freeze protection, pay attention to the fact that
intake pressure will be lower, the unit's performance will be lower and water pressure drops will be greater. All unit-
protection methods, such as anti-freeze, and low-pressure protection will need to be reset. Before insulating water
piping, check that there are no leaks.
CAUTION: Install a mechanical water filter at the water outlet of each heat exchanger. Failure to install the filter
allows access of solid particles and / or welding slag inside the heat exchanger. We recommend the installation of a
filter having a filtering net with holes not exceeding 0.5 mm in diameter.
Trane cannot be held responsible for any damage to heat exchangers due to the lack of good quality water filters.
** If the unit is a modular one, the water filter and the flow switch are on board the unit so the installation of water
filter and flow switch in the customer plant is not needed.
8.1.1 Calculation of minimum water content and flow rates
To grant a perfect running, the unit needs a water content according to the following formulas:
Recommended water content of
FLEX II
155
160
165
170
175
177
180
100
115
125
135
Cold water heat production
the plant
[m3]
0,47
0,52
0,54
0,57
0,62
0,65
0,68
0,84
0,97
1,05
1,14
Minimum water
K flow to the heat
exchanger
[m3/h]
199,2 5,8
195,3 6,5
193,4 6,8
191,7 7,2
82,9 7,8
82,1 8,2
81,4 8,5
78,2 10,6
42,0 12,1
41,4 13,2
40,8 14,2
Maximum water
flow to the heat
exchanger
[m3/h]
15,5
17,2
18,1
19,1
20,8
21,8
22,8
28,1
32,2
35,1
37,9
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