Carrier 30RAP010-060 Fill the Chilled Water Loop, Water Quality Characteristics, and Limitations

maintenance purposes, and that they be located where they can be prevented from freezing.

Step 4 — Fill the Chilled Water Loop

WATER SYSTEM CLEANING — Proper water system cleaning is of vital importance. Excessive particulates in the water system can cause excessive pump seal wear, reduce or stop flow, and cause damage of other components. Water quality should be maintained within the limits indicated in Table 3. Failure to maintain proper water quality may result in heat exchanger failure.

CAUTION

Failure to properly clean all piping and components of the chilled water system before unit start-up may result in plugging of the heat exchanger, which can lead to poor per- formance, nuisance alarms and damage from freezing. Freezing damage caused by an improperly cleaned system represents abuse and may impair or otherwise negatively affect the Carrier product warranty.

1.Install a temporary bypass around the chiller to avoid cir- culating dirty water and particulates into the pump pack- age and chiller during the flush. Use a temporary circulat- ing pump during the cleaning process. Also, be sure that there is capability to fully drain the system after cleaning. (See Fig 14.)

2.Be sure to use a cleaning agent that is compatible with all system materials. Be especially careful if the system contains any galvanized or aluminum components. Both detergent-dispersant and alkaline-dispersant cleaning agents are available.

3.It is a good idea to fill the system through a water meter. This provides a reference point for the future for loop volume readings, but it also establishes the correct quantity of cleaner needed in order to get the required concentration.

4.Use a feeder/transfer pump to mix the solution and fill the system. Circulate the cleaning system for the length of time recommended by the cleaning agent manufacturer.

a.After cleaning, drain the cleaning fluid and flush the system with fresh water.

b.A slight amount of cleaning residue in the system can help keep the desired, slightly alkaline, water pH of 8 to 9. Avoid a pH greater than 10, since this will adversely affect pump seal components.

c.A side stream filter is recommended (see Fig. 15) during the cleaning process. Filter side flow rate should be enough to filter the entire water volume

every 3 to 4 hours. Change filters as often as neces- sary during the cleaning process.

d. Remove temporary bypass when cleaning is complete.

Table 3 — Water Quality Characteristics

and Limitations

WATER CHARACTERISTIC		QUALITY LIMITATION
Alkalinity (HCO -)		70 – 300 ppm
	3
Sulfate (SO 2-)		Less than 70 ppm
	4
HCO	-/SO 2-	Greater than 1.0
3	4
Electrical Conductivity		10 – 500 μS/cm
pH		7.5 – 9.0
Ammonium (NH3)		Less than 2 ppm
Chorides (Cl-)		Less than 300 ppm
Free chlorine (Cl2)		Less than 1 ppm
Hydrogen Sulfide (H2S)*		Less than 0.05 ppm
Free (aggressive) Carbon		Less than 5 ppm
Dioxide (CO2)†
Total Hardness (dH)		4.0 – 8.5
Nitrate (NO3)		Less than 100 ppm
Iron (Fe)		Less than 0.2 ppm
Aluminum (Al)		Less than 0.2 ppm
Manganese (Mn)		Less than 0.1 ppm

*Sulfides in the water quickly oxidize when exposed to air, requiring that no agitation occur as the sample is taken. Unless tested immediately at the site, the sample will require stabilization with a few drops of one Molar zinc acetate solution, allowing accurate sulfide determination up to 24 hours after sampling. A low pH and high alkalinity cause system problems, even when both values are within the ranges shown. The term pH refers to the acidity, basicity, or neutrality of the water supply. Below 7.0, the water is considered to be acidic. Above 7.0, water is considered to be basic. Neutral water contains a pH of 7.0.

†Dissolved carbon dioxide can either be calculated from the pH and

total alkalinity values, shown below, or measured on the site using a test kit. Dissolved Carbon Dioxide, PPM = TA x 2[(6.3-pH)/0.3]where TA

= Total Alkalinity, PPM as CaCO3.

A 40-mesh strainer with a blow-down valve is standard on all 30RAP units, both with and without hydronic packages. The blow-down valve allows removal of particulates caught in the strainer without complete removal of the screen. A female NPT connection is provided on the valve, allowing hose con- nection for drainage outside the unit.

The Carrier ComfortLink™ controls provided have a built- in feature to remind building owners or operators to clean the strainer by discharging the blow-down valve at a pre-set time interval. Properly installed and cleaned systems will rarely need the strainer cleaned after the initial fill. This time interval is user-configurable.

Distribution Pump

Chiller 1

Chiller 2

Decoupler	Expansion
	Tank(s)

Zone 1

Air Separator with Vent

Zone 2

Zone 3

NOTE: Expansion tanks in the 30RAP hydronic kits must be disconnected for chillers placed parallel in the primary water loop.

Fig. 13 — Typical Air Separator and Expansion Tank Location on Primary-Secondary Systems

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