Carrier AQUAZONE 50PSW036-360 Installation And Service Instructions Manual page 6

CONDITION
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
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
Langelier Saturation Index
Iron Fouling
Iron Fe 2+ (Ferrous)
(Bacterial Iron Potential)
Iron Fouling
Corrosion Prevention††
pH
Hydrogen Sulfide (H S)
2
Ammonia Ion as Hydrox-
ide, Chloride, Nitrate and
Sulfate Compounds
Maximum Chloride Levels
Erosion and Clogging
Particulate Size and
Erosion
LEGEND
HWG— Hot Water Generator
HX — Heat Exchanger
N/A — Design Limits Not Applicable Consid-
ering Recirculating Potable Water
NR — Application Not Recommended
SS — Stainless Steel
*Heat exchanger materials considered are copper, cupronickel,
304 SS (stainless steel), 316 SS, titanium.
†Closed recirculating system is identified by a closed pressurized
piping system.
**Recirculating open wells should observe the open recirculating
design considerations.
UNIT LOAD PIPING — For applications with wide temper-
ature variation such as heating/cooling coils:
• Use piping materials that are rated for the maximum tem-
perature and pressure combination. This excludes PVC
for most heating applications.
• Ensure load water flow in high temperature heating
applications is at least 3.2 L/m per kW to improve perfor-
mance and reduce nuisance high pressure faults.
• DO NOT employ plastic to metal threaded joints.
• Utilize a pressure tank and air separator vent system to
equalize pressure and remove air.
• Employ an 800-micron particulate strainer in both load
and source plumbing to protect the plate heat exchanger.
Table 2 — Water Quality Guidelines
HX CLOSED
MATERIAL* RECIRCULATING†
All N/A
All N/A
All N/A
All N/A
All N/A
6 - 8.5
All
Monitor/treat as needed.
All N/A
All N/A
Copper N/A
Cupronickel N/A
304 SS N/A
316 SS N/A
Titanium N/A
<10 ppm of particles and
a maximum velocity of
All 6 fps.
Filtered for maximum
800 micron size.
OPEN LOOP AND RECIRCULATING WELL**
pH < 7.5 and Ca Hardness, <100 ppm
If >7.5 minimize steel pipe use.
If <–0.5 minimize steel pipe use.
Based upon 150 F HWG and direct well, 85 F indirect well HX.
<0.2 ppm (Ferrous)
2+
If Fe (ferrous) >0.2 ppm with pH 6 - 8, O
<0.5 ppm of Oxygen
Above this level deposition will occur.
Minimize steel pipe below 7 and no open tanks with pH <8.
At H S>0.2 ppm, avoid use of copper and cupronickel piping of HXs.
2
Rotten egg smell appears at 0.5 ppm level.
Copper alloy (bronze or brass) cast components are okay to <0.5 ppm.
Maximum allowable at maximum water temperature.
50 F (10 C)
<20 ppm
<150 ppm
<400 ppm
<1000 ppm
>1000 ppm
<10 ppm (<1 ppm "sandfree" for reinjection) of particles and a maxi-
mum velocity of 6 fps. Filtered for maximum 800 micron size. Any par-
ticulate that is not removed can potentially clog components.
††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, requir-
ing 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 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.
To convert ppm to grains per gallon, divide by 17. Hardness in
mg/l is equivalent to ppm.
Swimming Pool Hot Tub Applications — Load heat ex-
changer should be isolated with secondary heat exchanger
constructed of anti-corrosion material in all chlorine/bromine
fluid applications.
Potable Water Applications
• Load coax material should always be vented double
walled for use in potable water systems.
• Ensure load water flow in high temperature heating
applications is at least 3.2 L/m per kW to improve perfor-
mance and reduce nuisance high pressure faults.
6
6.0 - 7.5
–0.5 to +0.5
<5 ppm check for
2
iron bacteria.
6 - 8.5
<0.5 ppm
<0.5 ppm
75 F (24 C) 100 F (38 C)
NR NR
NR NR
<250 ppm <150 ppm
<550 ppm <375 ppm
>550 ppm >375 ppm