Bacharach 11-9026 User manual

Bacharach, Inc.
625 Alpha Drive, Pittsburgh, PA 15238-2878
Phone: [phone] Fax: [phone]
Web: www.bacharach-inc.com
Printed in U.S.A. ® Registered Trandmarks
INSTRUCTION 11-9026
FYRITE® Gas Analyzer
CO2 and O2 Indicators
Operation/Maintenance
Rev. 7 - June 1998
®
20
16
12
8
4
%CO
2
0

WARRANTY
Bacharach, Inc. warrants to Buyer that at the time of delivery this Product will
be free from defects in material and manufacture and will conform substantially
to Bacharach Inc.’s applicable specifications. Bacharach’s liability and Buyer’s
remedy under this warranty are limited to the repair or replacement, at
Bacharach’s option, of this Product or parts thereof returned to Seller at the
factory of manufacture and shown to Bacharach Inc.’s reasonable satisfaction to
have been defective; provided that written notice of the defect shall have been
given by Buyer to Bacharach Inc. within one (1) year after the date of delivery of
this Product by Bacharach, Inc.
Bacharach, Inc. warrants to Buyer that it will convey good title to this Product.
Bacharach’s liability and Buyer’s remedy under this warranty of title are limited
to the removal of any title defects or, at the election of Bacharach, to the
replacement of this Product or parts thereof that are defective in title.
The warranty set forth in paragraph 1 does not apply to parts the Operating
Instructions designate as having a limited shelf-life or as being expended in
normal use.
THE FOREGOING WARRANTIES ARE EXCLUSIVE AND ARE GIVEN AND
ACCEPTED IN LIEU OF (I) ANY AND ALL OTHER WARRANTIES, EXPRESS
OR IMPLIED, INCLUDING WITHOUT LIMITATION THE IMPLIED
WARANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
PURPOSE: AND (II) ANY OBLIGATION, LIABILITY, RIGHT, CLAIM OR
REMEDY IN CONTACT OR TORT, WHETHER OR NOT ARISING FROM
BACHARACH’S NEGLIGENCE, ACTUAL OR IMPLIED. The remedies of the
Buyer shall be limited to those provided herein to the exclusion of any and all
other remedies including, without limitation incidental or consequential dam-
ages. No agreement varying or extending the foregoing warranties, remedies or
this limitation will be binding upon Bacharach, Inc. unless in writing, signed by
a duly authorized officer of Bacharach.
NOTE: Gaskets are considered consumable items and are excluded
from the terms of this warranty.
CAUTION
Corrosive fluid is contained inside this unit.
These instructions should be thoroughly read
before operation is attempted.
Copyright © 1998 Bacharach, Inc., all rights reserved.
A

FYRITE SAFETY PRECAUTIONS
The operator (s) of this instrument should thoroughly familiarize themselves with the
applicable safety precautions before handling or using the FYRITE for gas analysis.
Review Figures 1a,1b, 1c and 1d on this page. Make certain to follow the steps
outlined below and read the fluid handling precautions for your personal safety.
1) Always use protective equipment such as safety goggles, gloves, and protective
clothing as illustrated in Figure 1a.
2) Read the instruction manual thoroughly. When filling the FYRITE with the
applicable fluid charge, use safety equipment and perform the operation in the
vicinity of running tap water (Figure 1b).
3) The FYRITE fluid should always be in the bottom reservoir before and during
sample introduction to the FYRITE. When venting the FYRITE to atmosphere,
hold the instrument in the vertical position and at a location away from your face
(Figure 1c).
4) NEVER vent FYRITE in the inverted position (with the plunger facing down-
ward). This will cause fluid to spill, which is corrosive and contains harmful
elements (Figure 1d).
NOTE: In the event of fluid spill - refer to Section 2.2 (FYRITE Handling
Precautions). For Maintenance - refer to Section 6.0.
®
20
16
12
8
%CO2
20
®
16
12
4
%CO
2
20
16
12
8
4
%CO
2
0
®
20
®
16
12
8
4
%CO2
0
Figure 1a. Protective equipment
required before attempting gas
analysis.
Figure 1b. Preparing to fill FYRITE
using recommended protective
safety equipment.
Figure 1c. Venting FYRITE to
atomsphere at 45° angle.
Figure 1d. NEVER vent FYRITE in
the inverted position, which will
cause fluid to spill.
i

ii
TABLE OF CONTENTS
1.0 DESCRIPTION ............................................................................................................................................. 1
2.0 FYRITE INSPECTION BEFORE AND DURING TEST .......................................................................... 1
2.1 Pre-Operational Check .................................................................................................................... 1
2.2 FYRITE FLUID HANDLING PRECAUTIONS ........................................................................... 2
3.0 BASIC FYRITE OPERATION PERCENT CO2AND 02........................................................................... 3
3.1 Determining CO2and O2FYRITE Fluid Strength ........................................................................ 7
3.2 Operating Precautions to Ensure Maximum Accuracy ................................................................. 7
3.2.1 Draining Fluid Droplets .................................................................................................8
3.3 FYRITE Temperature...................................................................................................................... 8
3.3.1 Temperature of Gas Sample ........................................................................................... 8
4.0 PRINCIPLE OF OPERATION..................................................................................................................... 9
5.0 APPLICATION INFORMATION ............................................................................................................. 10
5.1 FYRITE Absorbing Fluid ............................................................................................................. 10
5.1.1 FYRITE Refill Fluid (Storage Life, etc.) .................................................................... 10
5.2 FYRITE Operating Temperature Range ...................................................................................... 11
5.3 Typical FYRITE Applications...................................................................................................... 11
5.4 CO2FYRITE Only Combustion Testing...................................................................................... 12
5.4.1 Percent CO2Shows Volume of Excess Air ................................................................. 12
5.4.2 Too Much Excess Air Means Inefficient Combustion ............................................... 13
5.4.3 What is Proper CO2Value? .......................................................................................... 13
5.4.4 How To Calculate Combustion Efficiency ................................................................. 13
5.5 O2FYRITE Only Combustion Testing ........................................................................................ 13
5.5.1 Percent O2Shows Volume of Excess Combustion Air .............................................. 13
5.5.2 Too Much Excess Air Means Inefficient Combustion ............................................... 13
5.5.3 What is Proper O2Value?............................................................................................. 14
5.5.4 Measuring O2in Addition to CO2................................................................................ 14
5.5.5 Where is Percent CO2or O2Measured? ...................................................................... 14
5.6 Background Gases Affecting FYRITE Readings ........................................................................ 16
5.7 General FYRITE Applications ..................................................................................................... 17
5.8 Altitude Correction Table ............................................................................................................. 18
6.0 FYRITE MAINTENANCE ....................................................................................................................... 18
6.1 Increasing FYRITE Fluid To Proper Level ................................................................................. 18
6.1.1 Decreasing FYRITE Fluid to Proper Level ................................................................. 19
6.2 Checking FYRITE Fluid Strength................................................................................................ 19
6.2.1 CO2FYRITE Fluid Only .............................................................................................. 19
6.2.2 O2FYRITE Fluid Only................................................................................................. 21
6.3 Replacing FYRITE Fluid .............................................................................................................. 21
6.4 Inspection of FYRITE for Fluid Leakage ....................................................................................22
6.5 Cleaning FYRITE .......................................................................................................................... 24
6.6 Replacing FYRITE Plastic and Rubber Parts .............................................................................. 24
6.7 Aspirator Bulb - Sampling Assembly .......................................................................................... 26
6.8 Storing FYRITE and Refill Fluid ................................................................................................. 26
6.9 Replacing Saturator Filter Packing Part #11-0121 ..................................................................... 26
7.0 ILLUSTRATED PARTS LIST FYRITE CO2/O2...................................................................................... 29
7.1 FYRITE Illustrated Parts............................................................................................................... 30
7.2 FYRITE Sampling Assemblies ..................................................................................................... 31

Instruction 11-9026 Page 1
INSTRUCTIONS 11-9026
OPERATION/MAINTENANCE
BACHARACH FYRITE MODELS
CO2and O2INDICATORS
1.0 DESCRIPTION (Refer to Figure 1)
The FYRITE employs the well-known “Orsat” method of volumetric analysis involv-
ing chemical absorption of a sample gas, such as carbon dioxide or oxygen. The
reagent used to absorb carbon dioxide (CO2) is potassium hydroxide (dyed red), and
chromous chloride (blue) is the absorbent for oxygen (O2). The unique feature of the
FYRITE is that the absorbing fluid is also used as the indicating fluid so that one
vessel takes the place of both measuring burette and absorption pipette.
The body of the FYRITE is molded of clear high-strength plastic, comprises top and
bottom reservoirs and a center tube connecting the two reservoirs. The bottom of the
lower reservoir is sealed off by a synthetic rubber diaphragm that rests on a perfo-
rated metal plate. The upper reservoir is covered by a molded plastic cap that
contains a double-seated plunger valve. A spring holds this valve against a carefully
finished seat in the top cap providing a perfect seal which makes the instrument
spill-proof in any position. When the valve is partially depressed, the entire instru-
ment is open to the atmosphere and the instrument is, of course, is no longer spill-
proof.
The bottom reservoir is filled with the absorbing fluid, which extends about 1/4 inch
into the bore of the center tube when the instrument is held upright. The scale
position, mounted to one side of the center tube, is adjustable.
2.0 FYRITE INSPECTION BEFORE AND DURING TEST
CAUTION
Corrosive fluid is contained inside unit, instructions should be
thoroughly read before operation is attempted.
2.1 Pre-Operational Check
To ensure proper FYRITE operation and reliable results, check the following:
(a) With FYRITE vented and in a vertical position, it should be possible to adjust
scale zero to the top of the fluid column. Refer to FYRITE Operation for proper
setup (Section 3.0 Steps 1 through 5). If this is not possible, add or remove a
small amount of fluid per Section 6.1.

Page 2 Instruction 11-9026
(b) FYRITE Fluid Strength
To check fluid strength.
NOTE: When repeating procedures as outlined in Section 3.0
Steps 7 through 9 (absorbing and reading percent O2and
absorbing and reading percent CO2) and before venting
FYRITE to atmosphere for next sample, if the reading in-
creases by more than 1/2 percent for either CO2or O2, replace
the fluid.
It is often desirable to check fluid strength before taking the FYRITE to a location
where it will be used. It can be tested on sample atmospheric air (which contains
20.9% O2). Be certain to wet Filter Saturator when checking atmospheric air for
maximum accuracy. (See Section 6.9)
O2(Oxygen) Fluid - Fresh FYRITE fluid will absorb all O2from approximately 100
samples containing 10% O2.
CO2(Carbon Dioxide) Fluid - Fresh FYRITE Fluid will absorb all CO2from
approximately 350 samples containing 10% CO2.
(c) FYRITE Sampling Assembly - Always check sampling assembly for proper
(leak-free) operation as outlined in Section 6.7 before proceeding with test.
(d) Make certain wool in Filter Saturator Tube is moistened with water if using
either O2or CO2FYRITE in a noncombustible application where the gas sample
is not fully saturated with water vapor. Examples where filter-saturator must
be wetted include measuring CO2or O2in ambient air or from compressed gas
samples. Refer to Section 6.9 when replacing or moistening saturator (wool)
filter is required.
FYRITE OPERATION PRECAUTION: To prevent fluid
spill, never depress Plunger Valve to vent FYRITE when unit
is in the inverted or any other non-upright position. When
depressing Plunger Valve in the upright position to vent
FYRITE, hold at a slight angle away from the operator’s face.
2.2 FYRITE FLUID HANDLING PRECAUTIONS
CAUTION
FYRITE fluids used in the CO2and O2analyzers are corrosive
and contain poisonous elements which must not be taken
internally. In the event of a spill or accidental body contact
with FYRITE fluid, read the following carefully.

Instruction 11-9026 Page 3
HAZARDS
Corrosive liquid causes burns. May cause blindness if splashed in eyes. Vapors are
irritating and may be harmful.
PRECAUTIONS
Prevent contact with eyes, skin and clothing. Wear eye protection and gloves. Do not
vent instrument until fluid has drained from top well. Do not vent instrument
(FYRITE) in inverted position.
FIRST AID
For contact with eyes: Immediately flush eyes with water 20 minutes. Get immedi-
ate medical attention.
For contact with skin: Immediately flush skin with water 20 minutes. Get immedi-
ate medical attention.
For inhalation overexposure: If irritation develops, move victim to fresh air.
For swallowing: Do not induce vomiting. Give two glasses of water or milk if con-
scious and not convulsing. Get immediate medical attention.
Refer to the material safety data sheet for further information.
3.0 BASIC FYRITE OPERATION PERCENT CO2AND 02
Four basic steps are required when making an analysis, many being common to both
the CO2and O2FYRITE.
FYRITE MODEL CO2FYRITE MODEL O2
(Red Fluid) (Blue Fluid)
(a) Vent and adjust scale zero. (a) Vent and adjust scale zero.
(b) Pump sample into FYRITE. (b) Pump sample into FYRITE.
(c) Absorb CO2from sample. (c) Absorb O2from sample.
(d) Read % CO2on scale. (d) Read % O2on scale.
NOTE: To prevent warming of FYRITE fluid during analysis,
hold FYRITE by the fins only.

Page 4 Instruction 11-9026
CO2FYRITE OPERATION O2FYRITE OPERATION
(RED FLUID) (BLUE FLUID)
1. Hold upright (Fig. 1) and
away from face. Depress
Plunger Valve (momen-
tarily) to vent FYRITE,
and release.
2. Invert FYRITE (Fig. 2).
Hold at slight angle to
drain fluid into top
reservoir.
3. Turn upright. Hold
FYRITE at 45° angle
(Fig. 3) momentarily to
allow fluid droplet
drainage into bottom
reservoir.
4. Hold FYRITE in upright
(Fig. 4) position and away
from face. Depress
Plunger Valve (momen-
tarily) and release.
Figure 1
Figure 2
Figure 3
Figure 4
1. Hold upright (Fig. 1) and
away from face. Depress
Plunger Valve (momen-
tarily) to vent FYRITE,
and release.
2. Invert FYRITE (Fig. 2) to
absorb O2drawn into
FYRITE whenever
Plunger Valve is de-
pressed). Hold at slight
angle to drain fluid into
top reservoir.
3. Turn upright. Hold
FYRITE at 45° angle to
drain fluid into bottom
reservoir. Turn upright.
Repeat sequence of Steps
1, 2, and 3 twice until
fluid level does not drop
more that 1/2% when
Plunger Valve is de-
pressed. Turn upright.
Hold FYRITE at 45°
angle (Fig. 3) momen-
tarily until excess fluid
droplets have been
drained from inside
surfaces.
4. Hold FYRITE in upright
(Fig. 4) position and away
from face. Note fluid level
in column. Depress
Plunger Valve (momen-
tarily), and release.

Instruction 11-9026 Page 5
Figure 5
Figure 5a
Figure 5b
Figure 6
CO2FYRITE OPERATION O2FYRITE OPERATION
(RED FLUID) (BLUE FLUID)
5. Holding FYRITE upright
(Fig. 5), loosen locknut at
rear of scale. Slide scale
(Fig. 5a) until top of fluid
column lines up with zero
line on scale (Fig. 5b).
Tighten scale locknut.
NOTE: When setting
scale zero, hold FYRITE
vertically as shown and
level with eyes while
sighting across scale to
top of fluid column.
6. To pump gas sample into
FYRITE (Fig. 6), insert
open end of metal
sampling tube into area
bearing gas for analysis.
Hold FYRITE in upright
position and place
sampling assembly
rubber connector tip over
the Plunger Valve.
Depress Plunger Valve
firmly with connector tip.
Pump sample by squeez-
ing and releasing
aspirator bulb 18 times.
During 18th bulb squeeze
(with bulb held deflated)
release connector tip and
Plunger Valve.
5. Holding FYRITE upright
(Fig. 5), loosen locknut at
rear of scale. Slide scale
(Fig. 5a) until top of fluid
column lines up with zero
line on scale (Fig. 5b).
Tighten scale locknut.
NOTE: When setting
scale zero, hold FYRITE
vertically as shown and
level with eyes while
sighting across scale to
top of fluid column.
6. To pump gas sample into
FYRITE (Fig. 6), insert
open end of metal
sampling tube into area
bearing gas for analysis.
Hold FYRITE in upright
position and place
sampling assembly
rubber connector tip over
the Plunger Valve.
Depress Plunger Valve
firmly with connector tip.
Pump sample by squeez-
ing and releasing
aspirator bulb 18 times.
During 18th bulb squeeze
(with bulb held deflated)
release connector tip and
Plunger Valve.

Page 6 Instruction 11-9026
7. Absorb sample gas into
FYRITE by inverting
until fluid drains into top
reservoir (Fig. 7). Then
turn upright (Fig. 8) to
drain fluid into bottom
reservoir. Repeat this
step once.
8. Hold FYRITE at 45°
angle (Fig. 9) momen-
tarily to allow fluid
droplets to drain into the
bottom reservoir.
9. With FYRITE held
upright (Fig. 10), permit
fluid in column to
stabilize a few seconds,
then immediately read %
carbon dioxide on scale at
the point corresponding
to top of the fluid column.
CO2FYRITE OPERATION O2FYRITE OPERATION
(RED FLUID) (BLUE FLUID)
7. Absorb sample gas into
FYRITE by inverting
until fluid drains into top
reservoir (Fig. 7). Then
turn upright (Fig. 8) to
drain fluid into bottom
reservoir. Repeat this
step three (3) more times
(four complete inversions
total).
8. Hold FYRITE at 45°
angle (Fig. 9) momen-
tarily to allow fluid
droplets to drain into the
bottom reservoir.
9. With FYRITE held
upright (Fig. 10), permit
fluid in column to
stabilize a few seconds,
then immediately read %
oxygen on scale at the
point corresponding to
top of the fluid column.
Figure 7
Figure 8
Figure 9 Figure 10

Instruction 11-9026 Page 7
10. This step completes CO2or O2FYRITE gas sample analysis. A few points to
remember when reading the FYRITE:
(a) FYRITE accuracy is within ±1/2% CO2or O2compared to actual value.
(b) Always handle FYRITE by fins to ensure body heat is not absorbed by fluid.
(c) A delay in reading of 5 or 10 seconds may decrease accuracy of reading
slightly but longer delays may cause substantial error.
(d) The FYRITE is calibrated to indicate on a “dry” basis for flue gas samples,
which are normally fully saturated with moisture. Failure to artificially
moisten wool packing in Filter Saturator Tube when actual sample is not
fully saturated will cause FYRITE to read slightly low.
Therefore, make certain wool packing in Filter Saturator Tube is suffi-
ciently moistened with water for accurate results on non-flue gases. Avoid
excessive moisture which can be drawn into the Aspirator Bulb and forced
into the FYRITE during sampling.
CAUTION
Never depress plunger valve to vent FYRITE in the inverted
position. This will cause fluid to spill, which is corrosive and
contains poisonous elements. In the event of a spill, read Instruc-
tions in Section 2.2 FYRITE fluid handling precautions.
3.1 Determining CO2and O2FYRITE Fluid Strength
FYRITE Fluid strength can be conveniently checked immediately after the first
sample reading. Without venting, repeat the absorbing operations (Steps 7 through
9) by inverting FYRITE again and positioning upright until all fluid drains to the
bottom reservoir. Observe scale reading. An increase of more than 1/2% CO2or O2in
the second reading as compared to the first indicates a need for fluid replacement.
3.2 Operating Precautions to Ensure Maximum Accuracy
Locate top of fluid column (refer to Fig. 11). The surface at the top of the fluid
column (meniscus) in the small, center bore will be dish-shaped as shown in Fig-
ure 11. Either the high or low point of this dish-shaped surface may be used to
locate top of fluid column providing the same point is always used both for setting
scale zero and reading percent CO2or O2. Obviously, using high point for one
operation and low point for the other will cause an error.
Best practice is to use high point of this fluid surface just at the small center bore
wall. In setting scale zero or reading percent CO2or 02, hold FYRITE vertically and
level with eyes and sight across scale to top of fluid column.

Page 8 Instruction 11-9026
3.2.1 Draining Fluid Droplets
For maximum accuracy, it is important to form the habit of following a standard
procedure in this operation and to use the same procedure both before adjusting
scale zero and before reading percent CO2or O2.
3.3 FYRITE Temperature
The FYRITE temperature should be at or close to the temperature of the working
environment where the analysis is being made and should not be subject to sudden
temperature changes. If FYRITE is carried from cooler to warmer location or vice
versa, expose FYRITE to new temperature condition to permit uniform temperature
stabilization. Usually 15 or 20 minutes will suffice, except when extreme tempera-
ture variations are involved. Temperature stabilization can also be accelerated by
inverting FYRITE frequently.
3.3.1 Temperature of Gas Sample
The gas sample as it enters FYRITE should be cooled (or warmed if sampling cool
gases) to same (ambient) temperature as the FYRITE.
Capacity of Standard Aspirator Bulb and Sampling Assembly (Part # 11-7029) to
cool the gas sample is sufficient if the temperature of gas being sampled does not
exceed 850°F (454°C), even where a large number of consecutive samples are
required if there is an interval of not less than 5 minutes between samples.
FYRITE indicators operate over a wide temperature range. They may be exposed to
ambient temperatures from –30° to 150°F (–34° to 66° C). Gases up to 850° F
(454° C) may be tested with Standard Aspirator Sampling Assembly (11-7029).
Special sampling equipment for high temperatures and unsaturated gas samples are
listed in Section 7.2. FYRITE Sampling Assemblies.
®
20
16
12
8
4
%CO2
0
Top of
Fluid
Column
Figure 11. Locating Top of Fluid Column.

Instruction 11-9026 Page 9
4.0 PRINCIPLE OF OPERATION
(Refer to Figures 12, 13, and 14)
Figure 12. When plunger
valve is depressed, a gas
sample is pumped through
top reservoir with center
bore is sealed off.
Figure 13. When plunger
valve is released, the gas
sample is locked into
FYRITE and the top
reservoir is opened to
center bore so that gas
sample can pass through
absorbing fluid.
Figure 14. Absorption of
gas sample by fluid creates
suction, which causes
diaphragm to flex up and
fluid to rise in center bore
to replace gas absorbed.

Page 10 Instruction 11-9026
To make a test with the FYRITE, the metal Sampling Tube at one end of Sampling
Assembly Hose is inserted into the gas to be analyzed. The rubber Connector Plug at
the other end of the Rubber Hose is then firmly pressed down on the spring-loaded
Valve of the instrument (See Figure 12). This simultaneously opens a passage into
the Top Reservoir and seals off the center bore.
Next, a sample of the gas is pumped into the Top Reservoir by squeezing the rubber
Aspirator Bulb. At least 18 bulb squeezes are required to assure that the rubber
Sampling Hose and the Top Reservoir of the FYRITE are thoroughly purged of the
previously analyzed sample. During the 18th Aspirator Bulb squeeze and immedi-
ately before releasing Bulb, the finger is lifted from the Connector Plug, which
automatically returns the Plunger Valve to upper position against its top seat.
Refer to Figure 13. With the Valve in this position, the final 60 cc of the gas sample
is locked into the FYRITE and the Top Reservoir is opened to the center bore so that
the gas sample can pass to the absorbing fluid. The FYRITE is then inverted, forcing
the gas sample to bubble through the absorbing solution which absorbs either CO2
or O2depending on the type FYRITE in use.
Refer to Figure 14. The instrument is then turned and held upright. Absorption of
the CO2or O2by the absorbing fluid creates a suction, which causes the Diaphragm
at the bottom to flex upward permitting the level of the absorbing fluid to rise in the
center tube an amount proportional to the gas absorbed. The scale indication
corresponding to the top of the fluid column is then read as a percentage of gas
absorbed by the FYRITE fluid.
5.0 APPLICATION INFORMATION
FYRITE Analyzers are available for either Carbon Dioxide or Oxygen analysis, and
each of these models is made in the three scale ranges shown in Section 5.3. All six
instruments are similar in appearance and size, but they differ in important con-
struction details, as well as in absorbing fluids.
5.1 FYRITE Absorbing Fluid
FYRITE absorbing fluid is selective in the chemical absorption of carbon dioxide or
oxygen respectively. Therefore, the FYRITE’s accuracy is well within the range
required for industrial and professional applications, and does not depend upon
complicated sequential test procedures. Furthermore, the FYRITE readings are
unaffected by the presence of most background gases in the sample.
The appearance of a dark red fluid floating on top of CO2FYRITE solution is
entirely normal. The darker fluid consists of a small amount of material added to
prevent excessive foaming at the meniscus and improves readability.
5.1.1 FYRITE Refill Fluid (Storage Life, etc.)
FYRITE refill bottles should be stored at room temperature (70° F [21° C]) in the
carton provided, and placed in use within one year.
NOTE: Before opening refill bottle, read the label and make
certain to observe all precautions.

Instruction 11-9026 Page 11
FYRITE CO2refill fluid may develop a white insoluble precipitate upon aging. The
precipitate does not affect fluid performance in any way, but if present, should be
filtered out to prevent adherence to internal surfaces of the FYRITE.
To filter, place a clean piece of thin cloth or netting loosely over the open CO2
FYRITE and slowly pour refill contents into top reservoir. Before disposing of cloth,
rinse thoroughly with water. FYRITE fluid is corrosive!
FYRITE O2refill fluid reacts very rapidly with oxygen in air. Oxidation of absorbent
can be prevented by purging the FYRITE body with Nitrogen, natural gas or other
oxygen-free gas, just before filling, and by maintaining a stream of this gas around
mouth of the bottle (see Figure 21) while its contents are emptied into the FYRITE.
Another method for refilling the O2FYRITE (and still limiting the oxidation of the
absorbent) is to invert the unit and place it over the 60 cc bottle of fluid. Then invert
both so that the FYRITE is now upright and the O2fluid is filling the instrument
(see Figure 21a). Immediately install plastic Top Cap Ring without delay. This
method helps to minimize oxidation and improve the life of the fluid.
5.2 FYRITE Operating Temperature Range
The FYRITE indicators operate over a wide temperature range, and may be exposed
to ambient temperatures from –30° to 150° F. (–34° to 66°C). Gases up to 850° F
(454° C) may be tested with standard aspirator sampling equipment (11-7029).
Special sampling equipment to reduce high combustion gas temperatures (2000° F
[1093° C]) to usable FYRITE temperature (ambient) and assemblies with extra large
saturators for dry gas sampling are listed in Section 7.2, FYRITE Sampling Assemblies.
NOTE: Remember, for most accurate results, the FYRITE
must be at temperature equilibrium with its surroundings
(ambient temperature) and the incoming gas sample at the
same temperature as the FYRITE.
5.3 Typical FYRITE Applications
Listed below are six models of FYRITE Indicators and two Aspirator Sampling
Assemblies with part numbers identifying their application.
Bacharach Part Numbers
Aspirator Complete
For Scale Sampling Kit with
Testing Range FYRITE Assy. Fluid Case
Carbon 0 - 7.6% 11-7042 11-7029 10-5100 10-5053
Dioxide 0 - 20% 11-7032 11-7029 10-5057 10-5000
0 - 60% 11-7034 11-7029 10-5057 10-5032
0 - 7.6% 11-7044 11-7039 10-5103 10-5054
Oxygen 0 - 21% 11-7036 11-7029 10-5060 10-5011
0 - 60% 11-7038 11-7029 10-5060 10-5046

Page 12 Instruction 11-9026
TYPICAL APPLICATIONS WITH FULL SIZE
SECTIONS OF FYRITE SCALES
0-7.6% CO2or O2
CO2tests of controlled atmospheres in fruit,
vegetable, and meat storage rooms. Oxygen
determination in flammable gases. Oxygen tests
to check atmospheres made inert with nitrogen
(silos, fuel tanks, etc.)
0-20% CO2or 0-21% O2
Flue gas combustion tests, oxygen deficiency tests,
and CO2tests of heat treating atmospheres.
Checking oxygen concentrations in hydrogen-cooled
generators and oil-sealed inert-gas transformers.
0-60% CO2or O2
Checking CO2in inert gas blankets in tankers and
barges carrying gasoline and other combustibles.
CO2tests on lime kilns. Checking CO2in sewage
plant digesters. Oxygen tests in connection with
oxygen and gas anesthesiology.
5.4 CO2FYRITE Only Combustion Testing
5.4.1 Percent CO2Shows Volume of Excess Air (Refer to Figure 15)
For any given fuel, theoretical maximum percent CO2(Ultimate CO2) would be
produced when exactly enough air (but no excess air whatsoever) is supplied to burn
all of the fuel. As increasing amounts of excess air are supplied, percentage CO2
naturally decreases from theoretical Ultimate CO2due to the diluting effect of
excess air.
Thus, measuring percent CO2is also a method of indicating excess air to ensure that
enough is supplied to permit clean combustion without adding so much that combus-
tion efficiency is unnecessarily decreased.

Instruction 11-9026 Page 13
5.4.2 Too Much Excess Air Means Inefficient Combustion
Excess combustion air is heated and carries some of this heat to the flue where it is
wasted. The FYRITE CO2Analyzer is used to adjust combustion excess air to a
minimum (maximum CO2), which will permit clean efficient combustion.
Calculation of combustion efficiency is possible (assuming complete combustion) if
percentage of CO2and net temperature of combustion products are known.
5.4.3 What is Proper CO2Value?
Proper CO2is that which will ensure complete, clean combustion with some safety
margin for variations in fuel, draft, atmospheric conditions, and mechanical wear.
Consult manufacturer of heating equipment for specific recommendations. Generally
accepted values for good combustion practice in residential furnaces and boilers
when firing the following fuels are:
Natural Gas ...... 8 to 9.5% CO2
No.2 Oil ............ 10 to 12.5% CO2
These are only guidelines, however, and in all cases recommendations of the equip-
ment or fuel supplier would also include recommendations for allowable smoke (oil
firing) or combustibles (gas firing), which are undesirable combustion by-products.
Testing for smoke, CO, or combustibles is important since in extreme fuel rich
firing, high CO2values also occur (see Figure 16).
5.4.4 How To Calculate Combustion Efficiency
Measure percent CO2in flue gases with FYRITE. Then measure flue gas tempera-
ture with a suitable thermometer (e.g., TEMPOINT) at the same sampling point.
Deduct temperature of basement or combustion air supplied from measured flue gas
temperature to obtain net flue gas temperature. Use a Bacharach FIRE EFFI-
CIENCY FINDER to calculate combustion efficiency. Instructions for using the
FIRE EFFICIENCY FINDER are printed on the face of this slide rule calculator.
5.5 O2 FYRITE Only Combustion Testing
5.5.1 Percent O2Shows Volume of Excess Combustion Air (Refer to Fig. 15)
All fuels require some excess air (in addition to air theoretically required to burn the
fuel) to ensure clean, complete combustion. As the amount of this excess air in-
creases, the percentage of O2in combustion products increase.
5.5.2 Too Much Excess Air Means Inefficient Combustion
Excess combustion air is heated and carries some of this heat to the flue where it is
wasted. The FYRITE O2analyzer is used when adjusting combustion air to mini-
mum excess air (minimum O2) which will permit clean, efficient combustion.

Page 14 Instruction 11-9026
5.5.3 What is Proper O2Value?
Proper O2content for any fuel fired is the lowest O2value that will ensure complete,
clean combustion with adequate safety margin for variations in fuel, draft, atmo-
spheric conditions, and mechanical wear. Consult manufacturer of heating equip-
ment or local authorities for specific recommendations. Figure 15 illustrates the
relationship between CO2, excess air and oxygen for gas and oil.
For guidance, it should be added that modern boilers are capable of 80% or greater
combustion efficiency. Rough guidelines for setting conventional power burners are
10-15% excess air for natural gas and 15-20% excess air for oil, with little or no
smoke and carbon monoxide formation.
5.5.4 Measuring O2 in Addition to CO2
Figure 16 illustrates why it is good practice to measure oxygen, in addition to carbon
dioxide, when firing gaseous fuels. Note that the same CO2reading can be obtained
on both sides of the stoichiometric (or perfect) mixture. Carbon dioxide alone cannot
define proper excess air operation for gaseous fuels.
A check must also be made for the presence of oxygen, which confirms operation
with excess air. Gaseous fuels should also be checked for presence of carbon monox-
ide (CO) in the flue gases and adjusted for either “no CO” or to conform to applicable
safety regulations.
5.5.5 Where is Percent CO2 or O2 Measured? (Refer to Figure 17)
For residential and most commercial and industrial combustion units, percent CO2
or O2is measured by analyzing gas sample obtained through a 1/4-inch diameter
hole located between the flue outlet (breeching) and any mechanical opening in the
flue such as the barometric draft regulator or draft diverter. Best practice is to
locate sampling hole at least six inches upstream from such flue openings. The
metal FYRITE Sampling Tube should extend at least 2-1/2 inches into the flue
gases.
For larger installations, consult manufacturer of combustion equipment for special
instructions regarding sampling point, special sampling tube required, or advice on
averaging readings.
Residential gas furnaces with built-in draft diverter (gas designed) will require the
FYRITE metal Sampling Tube to be inserted as illustrated in Figure 17 to avoid
dilution of flue gas sample.
Additional information on residential furnace combustion testing may be obtained
from the following Bacharach publications:
Bulletin 4097 - Technical Combustion Brochure

Instruction 11-9026 Page 15
Figure 15. Relation between Oxygen, CO2and excess
air in flue gases for Natural Gas and Fuel Oil.
THEORETICAL EXCESS AIR CURVE
PERCENT EXCESS AIR
STOICHIOMETRIC MIX
Figure 16. CO2measurements alone do not determine
combustion air setting when firing gaseous fuels.

Page 16 Instruction 11-9026
5.6 Background Gases Affecting FYRITE Readings
As a rule of thumb, background gases/vapors may be present in concentrations up to
1/2% by volume (5000 ppm) before they present a significant interference problem to
the CO2or O2FYRITE (20/21% ranges).
An exception exists with the action of ammonia on Oxygen FYRITE Fluid. Ammonia
neutralizes the acidic solution of chromous chloride, and therefore use of the O2
FYRITE with even trace amounts of ammonia in the backgrounds is not advised
unless suitable filters are used.
Inert gases, even in concentrations approaching 100% by volume, do not interfere
with either the CO2or O2FYRITE. In general, interferences can be of a chemical
(chemical reaction initiated) or a mechanical nature, with resultant error, but are
also given up by the solution when the sample no longer contains the interfering
substance. They can therefore be compensated for by saturating the FYRITE
solution with samples containing the mechanical interferant as long as the back-
ground stays reasonably constant. Usually 3 or 4 tests are sufficient to saturate
FYRITE solution with the mechanical interferant in question.
TYPICAL TYPE OF APPROXIMATE
INTERFERENCE INTERFERENCE EFFECT
(CO2FYRITE)
All Acid Gases Chemical 1:1
(SO2, H2S, Hydro-
cynanic Acid,
Cyanogen, etc.).
TYPICAL TYPE OF APPROXIMATE
INTERFERENCE INTERFERENCE EFFECT
(O2FYRITE)
Acetone Chemical 1:1
Acetylene Chemical 1:1
and other
unsaturated
hydrocarbons
CO2Mechanical, 20% CO2Can be zeroed out up
background can be to approximately 30%
zeroed out in 3 to 4 CO2background.
tests if background
remains constant.
Ammonia Chemical Ammonia neutralizes
O2FYRITE solution
and instrument use on
this background is not
advised unless suit-
able filters are used.
Nitrous Oxide (N2O) Mechanical - - -