Bacharach FYRITE Gas Analyzer CO2 and O2 Indicators Installation and operation manual

Instruction 0011-9026 Page 1
Printed in U.S.A. ® Registered Trademarks
INSTRUCTION 0011-9026
FYRITE® Gas Analyzer
CO2 and O2 Indicators
Operation/Maintenance
Rev. 12 – December 2012
®
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 Bacha-
rach’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 replace-
ment 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 WARAN-
TIES 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 damages. 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 © 1998-2012 Bacharach, Inc., all rights reserved.
Register Your Warranty by Visiting
www.mybacharach.com

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 out-
lined 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 appli-
cable 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 ele-
ments (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 FY-
RITE using recommended protec-
tive safety equipment.
Figure 1c. Venting FYRITE to at-
omsphere at 45° angle.
Figure 1d. NEVER vent FYRITE in
the inverted position, which will
cause fluid to spill.

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 0011-9026 Page 1
INSTRUCTIONS 0011-9026
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 involving
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 instrument 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 posi-
tion, 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.

Instruction 0011-9026Page 2
(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 ab-
sorbing and reading percent CO2) and before venting FYRITE
to atmosphere for next sample, if the reading increases 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 maxi-
mum 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 ap-
proximately 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 de-
pressing 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 in-
ternally. In the event of a spill or accidental body contact with
FYRITE fluid, read the following carefully.

Instruction 0011-9026 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 (FY-
RITE) in inverted position.
FIRST AID
For contact with eyes: Immediately flush eyes with water 20 minutes. Get immediate
medical attention.
For contact with skin: Immediately flush skin with water 20 minutes. Get immediate
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 conscious
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.

Instruction 0011-9026Page 4
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 reser-
voir.
3. Turn upright. Hold FY-
RITE 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 FY-
RITE whenever Plunger
Valve is depressed). 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° an-
gle (Fig. 3) momentarily
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 0011-9026 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 sam-
pling assembly rubber
connector tip over the
Plunger Valve.
Depress Plunger Valve
firmly with connector tip.
Pump sample by squeez-
ing and releasing as-
pirator 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 sam-
pling assembly rubber
connector tip over the
Plunger Valve.
Depress Plunger Valve
firmly with connector tip.
Pump sample by squeez-
ing and releasing as-
pirator bulb 18 times.
During 18th bulb squeeze
(with bulb held deflated)
release connector tip and
Plunger Valve.

Instruction 0011-9026Page 6
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) momentari-
ly to allow fluid droplets
to drain into the bottom
reservoir.
9. With FYRITE held
upright (Fig. 10), per-
mit 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) momentari-
ly to allow fluid droplets
to drain into the bottom
reservoir.
9. With FYRITE held
upright (Fig. 10), per-
mit 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 0011-9026 Page 7
10. This step completes CO2or O2FYRITE gas sample analysis. A few points to re-
member 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 sufficiently
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 In-
structions 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 bot-
tom 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 Figure 11. Either
the high or low point of this dish-shaped surface may be used to locate top of fluid col-
umn 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.

Instruction 0011-9026Page 8
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 temperature
variations are involved. Temperature stabilization can also be accelerated by invert-
ing 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).
®
20
16
12
8
4
%CO2
0
Top of
Fluid
Column
Figure 11. Locating Top of Fluid Column.

Instruction 0011-9026 Page 9
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 FY-
RITE 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 cre-
ates suction, which causes
diaphragm to flex up and
fluid to rise in center bore
to replace gas absorbed.
4.0 PRINCIPLE OF OPERATION
(Refer to Figures 12, 13, and 14)

Instruction 0011-9026Page 10
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 rub-
ber 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 immediately
before releasing Bulb, the finger is lifted from the Connector Plug, which automati-
cally 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 CO2or O2
depending 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 correspond-
ing 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 construc-
tion 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 ox-
ygen 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 car-
ton provided, and placed in use within one year.
NOTE: Before opening refill bottle, read the label and make
certain to observe all precautions.

Instruction 0011-9026 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 CO2FYRITE
and slowly pour refill contents into top reservoir. Before disposing of cloth, rinse thor-
oughly 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).
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 tem-
perature as the FYRITE.
5.3 Typical FYRITE Applications
Listed below are six models of FYRITE Indicators and two Aspirator Sampling Assem-
blies with part numbers identifying their application.
Bacharach Part Numbers
For Test-
ing
Scale
Range
FY-
RITE
Aspirator Sam-
pling Assy.
Fluid Complete Kit
with Case
Carbon
Dioxide
0 - 7.6% 11-7042 11-7029 10-5100 10-5053
0 - 20% 11-7032 11-7029 10-5057 10-5000
0 - 60% 11-7034 11-7029 10-5057 10-5032
Oxygen 0 - 21% 11-7036 11-7029 10-5060 10-5011
0 - 60% 11-7038 11-7029 10-5060 10-5046
TYPICAL APPLICATIONS WITH FULL SIZE
SECTIONS OF FYRITE SCALES

Instruction 0011-9026Page 12
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 pro-
duced 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 CO2naturally
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.
5.4.2 Too Much Excess Air Means Inefficient Combustion

Instruction 0011-9026 Page 13
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 mini-
mum (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 temperature
with a suitable thermometer (e.g., TEMPOINT) at the same sampling point. Deduct
temperature of basement or combustion air supplied from measured flue gas tem-
perature to obtain net flue gas temperature. Use a Bacharach FIRE EFFICIENCY
FINDER to calculate combustion efficiency. Instructions for using the FIRE EFFI-
CIENCY 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 increases,
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 minimum
excess air (minimum O2) which will permit clean, efficient combustion.
5.5.3 What is Proper O2Value?

Instruction 0011-9026Page 14
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, atmospher-
ic conditions, and mechanical wear. Consult manufacturer of heating equipment 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 monoxide (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 CO2or
O2is measured by analyzing gas sample obtained through a 1/4-inch diameter hole lo-
cated 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 Sam-
pling 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 dilu-
tion of flue gas sample.
Additional information on residential furnace combustion testing may be obtained
from the following Bacharach publication:
Bulletin 4097 - Technical Combustion Brochure
5.6 Background Gases Affecting FYRITE Readings

Instruction 0011-9026 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.

Instruction 0011-9026Page 16
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 O2FY-
RITE 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 background 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
O
2FYRITE solution
and instrument use on
this background is not
advised unless suit-
able filters are used.
Nitrous Oxide (N2O) Mechanical - - -