Carrier 28QX - Manual (Page 25)

Fig. 30 — Bleed Screw Position
Run the heat exchanger pump by energizing the
collector loop. When the air has been bled, tighten
the screw.
CONTROL ADJUSTMENTS - The same control
timing on the adjustable aquastat must be made
here as was the case for the plain water system. See
the section on “Control Adjustments” in the
“Plain Water System Start-Up” instructions for
details.
Inhibitors (Field Supplied) — Procure an inhibitor
from local water treatment firm. Specify an
inhibitor of fungus, rust, scale, red water and
galvanic action. The stored fluid passes thru many
parts of the Solaround''''''' System composed of
different materials, each vulnerable to the effects
of these natural and chemical actions.
Add inhibitors to the water charge in thermal
storage tank. Tap water may be used if total
dissolved solids do not exceed 800 ppm. Other­
wise, dilute tap water with demineralized water to
reduce sohds below that level.
If the system is charged with antifreeze,
commercial automotive antifreeze solutions should
be used at 50% concentration to obtain the proper
inhibitor concentration.
Inhibitors will be depleted with time to a level
which may even increase corrosion rated beyond
that expected with uninhibited water. Therefore,
make bi-annual checks to test the inhibitor
strength, or replace the inhibitor, following the
manufacturer’s recommendation.
Suitable inhibitors for tap water are as follows:
1. For all copper piping systems with coated
concrete or fiberglass reinforced plastic storage
vessles, or steel vessels with plastic or rubber
liners:
NALCO 7SN-196 or equivalent. See specifica­
tion below.
Dosage: 1/4 lb per 1000 gallons (30 ppm).
2. For systems with uncoated steel tanks plus
copper piping:
NALCO 2532 or equivalent. See specification
below.
Dosage: 2 oz per gallon.
NALCO 7SN-196 is in a highly soluble, pulverized
form.
Color............................................................ White
Odor ............................................................ None
Density ............................................. 67 Ib/cu ft
pH of 1 % Solution ....................................... 12.3
Solubility in Water @ 75°F .
. . . Up to an 8%
clear solution
Si02 .............................................................. 30%
PO4................................................................ 25%
Very slightly hygroscopic
NALCO 2532 is a water soluble, blended liquid
product containing quaternary amine and organo-
tin compounds with the following properties:
Color.................................................Light yellow
Odor ..............................................................Mild
Specific Gravity (@ 25°C) ........................ 1.016
Density (@ 25°C)............................... 8.46 Ib/gal
Freeze Point ............................................ — 1.0°C
Flash Point................................................... None
pH (Neat)....................................................... 12.2
Do not apply to potable water or
domestic
water systems. Apply this product only as
specified.
Solar-Assisted Heat Pump Operating Modes
System Equipment:
1. Pump Package (34 WA/GL)
2. Compressor and O.D. Coil (38HQ)
3. Tri-X Coil (28QX)
4. Indoor Fan and Electric Heater (40FS/FQ)
5. Solar Collector Panels
MODE: SOLAR ENERGY COLLECTION
Controlling Mechanism:
• Solid State differential controller located in
pump package control box. Two thermistor
temperature sensors are remotely located. One
sensing collector panel temperature (Tc) and
the other sensing storage tank temperature (Ts).
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