Water Treatment; Antifreeze Protection On The Heat Exchangers - Trane CGCN Installation Operation & Maintenance

1 = Gauge
2 = Flexible connector
3 = Thermometer
4 = Isolating valve
5 = Pump
6 = Filter
Hydraulic connection heat recovery
WARNING! Install a mechanical filter at the entrance of each heat exchanger. Failure to install the mechanical
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. The manufacturer can not
be held responsible for any damage to heat exchangers due to the lack of a mechanical filter.

Water treatment

Before putting the unit into operation, clean the hydraulic circuit. Dirt, scales, corrosion residue and other
extraneous material can accumulate inside the heat exchanger and reduce its heat exchanging capacity.
Pressure drops can increase as well, thus reducing water flow. Proper water treatment therefore reduces the risk
of corrosion, erosion, scaling, etc. The most appropriate water treatment must be determined locally, according to
the type of system and to the local characteristics of the process water.
For units equipped with plate heat exchangers the filter should guarantee a filtration of particles until 0,8 mm.
Trane is not responsible for damages to or malfunctioning of the equipment caused by failure to treat water or by
improperly treated water.
Recommended water quality limits
PH (25°C)
Electrical conductivity S/cm (25°C)
Chloride ion (mg Cl / l)
-
Sulphate ion (mg SO / l)
24-
Alkalinity (mg CaCO / l)
3

Antifreeze protection on the heat exchangers

Evaporator and recovery exchangers anti-freeze protection
All evaporators are supplied with a thermostatically controlled anti-freeze electrical resistance, which provides
adequate anti-freeze protection up to –25°C. However, this method is not the only protection system against
freezing, unless the heat exchangers are completely emptied and cleaned with anti-freeze solution.
Two or more protection methods should be foreseen when designing the system as whole:
•
Continuous water flow circulation inside piping and exchangers.
•
Addition of an appropriate amount of glycol inside the water circuit
•
Additional heat insulation and heating of exposed piping
•
Emptying and cleaning of the heat exchanger during the winter season
It is the responsibility of the installer and/or of local maintenance personnel to ensure two or more of the
described antifreeze methods. Continuously verify, through routine checks, that appropriate anti-freeze protection
is maintained. Failure to follow the instructions above could result in damage to some of the unit's components.
Damage from freezing is not covered by the warranty.
6,8÷8,0 Total hardness (mg CaCO
800 Fe (mg Fe /l)
200 Sulphide ion (mg S
200 Ammunium ion (mg NH
100 Silica (mg SiO
/ l) 200
3
1.0
/ l) Absent
2 -
/ l) 1.0
4+
/ l) 50
2