Carrier AQUAZONE 50PSH, Installation, Start-Up And Service Instructions Manual

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LEGEND
Table 2 — Water Quality Guidelines
CONDITION HX MATERIAL
a
NOTE(S):
a. Heat exchanger materials considered are copper, cupronickel, 304 SS (stainless steel), 316 SS, titanium.
CLOSED
RECIRCULATING
b
b. Closed recirculating system is identified by a closed pressurized piping system.
OPEN LOOP AND RECIRCULATING WELL
c
c. Recirculating open wells should observe the open recirculating design considerations.
Scaling Potential — Primary Measurement
Above the given limits, scaling is likely to occur. Scaling indexes should be calculated using the limits below.
pH/Calcium Hardness
Method
All N/A pH < 7.5 and Ca Hardness, <100 ppm
Index Limits for Probable Scaling Situations (Operation outside these limits is not recommended.)
Scaling indexes should be calculated at 150°F for direct use and HWG applications, and at 90°F for indirect HX use. A monitoring plan should be
implemented.
Ryznar Stability Index All N/A
6.0 to 7.5
If >7.5 minimize steel pipe use.
Langelier Saturation Index All N/A
–0.5 to +0.5
If <–0.5 minimize steel pipe use.
Based upon 150°F HWG and direct well, 85°F indirect well HX.
Iron Fouling
Iron Fe
2+
(Ferrous)
(Bacterial Iron Potential)
All N/A
<0.2 ppm (Ferrous)
If Fe
2+
(ferrous) >0.2 ppm with pH 6 to 8, O
2
<5 ppm check for iron bacteria.
Iron Fouling All N/A
<0.5 ppm of Oxygen
Above this level deposition will occur.
Corrosion Prevention
d
d. If the concentration of these corrosives exceeds the maximum allowable level, then the potential for serious corrosion problems exists.
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
can cause system problems, even when both values are within 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 registers a pH of 7.0.
To convert ppm to grains per gallon, divide by 17. Hardness in mg/l is equivalent to ppm.
pH All
6 to 8.5
Monitor/treat as needed.
6 to 8.5
Minimize steel pipe below 7 and no open tanks with pH <8.
Hydrogen Sulfide (H
2
S) All N/A
<0.5 ppm
At H
2
S>0.2 ppm, avoid use of copper and cupronickel piping or HXs.
Rotten egg smell appears at 0.5 ppm level.
Copper alloy (bronze or brass) cast components are okay to <0.5 ppm.
Ammonia Ion as
Hydroxide, Chloride,
Nitrate and Sulfate
Compounds
All N/A <0.5 ppm
Maximum Chloride
Levels
Maximum allowable at maximum water temperature.
50°F (10°C) 75°F (24°C) 100°F (38°C)
Copper N/A <20 ppm NR NR
Cupronickel N/A <150 ppm NR NR
304 SS N/A <400 ppm <250 ppm <150 ppm
316 SS N/A <1000 ppm <550 ppm <375 ppm
Titanium N/A >1000 ppm >550 ppm >375 ppm
Erosion and Clogging
Particulate Size and
Erosion
All
<10 ppm of particles and
a maximum velocity of
6 fps. Filtered for
maximum 800 micron
size.
<10 ppm (<1 ppm “sandfree” for reinjection) of particles and a maximum
velocity of 6 fps. Filtered for maximum 800 micron size. Any particulate
that is not removed can potentially clog components.
Brackish All N/A
Use cupronickel heat exchanger when concentrations of calcium or
sodium chloride are greater than 125 ppm are present. (Seawater is
approximately 25,000 ppm.)
HWG —
Hot Water Generator
HX —
Heat Exchanger
N/A —
Design Limits Not Applicable Considering Recirculating Potable Water
NR —
Application Not Recommended
SS —
Stainless Steel