Solution Or Refrigerant Sampling; Solution Sample; Refrigerant Sample; Solution Analysis - Carrier 16JT Series Start Up & Operation Manual

Solution or Refrigerant Sampling —
tions pertaining to handling lithium bromide solution as
described in Solution and Refrigerant Charging section,
page 21.)
Take solution or refrigerant samples from the pump serv-
ice valve while the pump is operating.
Before taking a sample for analysis or absorber loss de-
termination, be sure machine is operating with steady load
and that Cycle-Guard™ valve has not been energized within
10 minutes prior to sampling.
Attach a hose adapter to the pump service valve. Do not
use copper or brass fittings when taking samples for analy-
sis; copper oxide can form and contaminate samples.
The solution pump normally discharges at above atmo-
spheric pressure, but the refrigerant pump discharges at a
vacuum, so the respective sampling procedures are
different.

SOLUTION SAMPLE

1. Fill a length of flexible tubing with water and connect
one end to the hose adapter. Place the free end in a con-
tainer of water. Be sure end is submerged (Fig. 29).
2. Open valve slightly. When container water level rises, wait
several seconds to purge the water from the tube. Then
remove tube end from water and fill sample container.
3. Turn off service valve and remove hose and adapter.
REFRIGERANT SAMPLE (Fig. 30)
1. Connect a clean, empty vacuum container to the pump
service valve with a length of flexible hose.
2. Connect a vacuum pump to the vacuum container with a
flexible hose and isolation valve.
3. Pull a deep vacuum on the container and close the iso-
lation valve.
4. Open the service valve slightly to drain refrigerant sample
into the container.
5. Turn off service valve, remove hose and adapter, and dis-
connect vacuum pump.
Fig. 29 — Adding or Removing Fluid
(See precau-
Fig. 30 — Refrigerant Sampling Technique
Solution Analysis —
sample gives indication of change in solution alkalinity and
depletion of inhibitor, and may indicate the degree of ma-
chine leak tightness.
Have the solution analyzed at least once a year or when-
ever there is an indication of a noncondensable problem. Take
the sample from the solution pump service valve while the
machine is running (see Solution or Refrigerant Sampling
section, this page). The sample concentration should be be-
tween 58% and 62% by weight for best results.
Solution analysis should be done by an approved lab-
oratory. The analysis interpretation and the adjustment rec-
ommendations should be made by a trained absorption
specialist.
Inhibitor —
cludes a lithium chromate inhibitor. The inhibitor is used in
conjunction with alkalinity control to minimize the amount
of hydrogen normally generated within the machine. Exces-
sive hydrogen generation interferes with machine perfor-
mance.
The inhibitor is gradually depleted during machine opera-
tion and occasional replenishment is necessary. Solution al-
kalinity also changes over a period of time and must be ad-
justed (see Solution Analysis, on this page).
IMPORTANT: Altering the inhibitor or using solution
and internal surface treatments not specified by the equip-
ment manufacturer may result in performance deterio-
ration and damage to the absorption machine.
34
Laboratory analysis of a solution
The initial charge of lithium bromide in-