3. Push the Calibration Cup over the sensor housing.

4. Attach a CO Span Gas Cylinder to the regulator.

Then apply span gas to the sensor by adjusting the regulator knob for a flow rate of 2 SCFH.

5. Allow span gas to flow until the displayed reading stabilizes – approx. 3 minutes. Then, using Calibration Tool 06-9453 (supplied in Calibration Tool /

Cup Kit 19-3242), turn the Span Adjust potentiometer until the displayed reading matches the concentration stamped on the Span Gas Cylinder.

6. Calibration is now complete. Turn off the Regulator and remove the calibration equipment.

Maintenance

Battery Replacement

Remove slotted screw from rear of instrument; then lift off front case.

Replace 9V Alkaline battery

(Duracell MN1604 or equiv.) in location shown in Figure 3; then reinstall front case.

Sensor Replacement

The sensor needs replaced when it can no longer be calibrated to the

Figure 3. Battery

Location

Span Gas Cylinder value using the Span Adjust potentiometer, or if it no longer responds to a CO source.

1. See Figure 4. Remove the screw from the rear of the instrument; then lift off the front case and remove the printed circuit board assembly.

2. Unplug the old sensor and remove its gasket.

Discard both items properly.

3. Inspect the sensor filter. Replace the filter if it has become contaminated with dirt.

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4. Remove wire-jumper (if installed) from pins of new sensor; plug in sensor and install the new gasket supplied; then reassemble the instrument.

5. Wait 30 minutes; then calibrate the new sensor.

C O

S E N S O R

F I L T E R

G A S K E T

W A R N I N G !

R e m o v e j u m p e r - w i r e

( i f i n s t a l l e d ) f r o m p i n s b e f o r e i n s t a l l a t i o n

Figure 4. Sensor Installation

Replacement Parts

Item Part No.

CO Sensor and Gasket ...................................... 19-7061

Filter ................................................................... 19-3244

Accessories

Item Part No.

Calibration Kit ................................................... 24-7059

Calibration Tool / Cup Kit ................................ 19-3242

Span Gas Cylinder, 100 ppm CO in air ............ 51-1994

Zero Gas Cylinder, 20.9% O

2

in Nitrogen ........ 51-7131

Bacharach Service Center

Replacement parts and accessories can be obtained by contacting the following Bacharach Service Center:

Bacharach, Inc., 625 Alpha Drive

Pittsburgh, PA 15238

Phone: (412) 963-2214 FAX: (412) 963-2606

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Instruction 19-9201

Rev. 3 – June 1999

Snifit

®

Model 50

Carbon Monoxide Analyzer

Introduction

Designed for HVAC professionals and utility personnel, the Snifit Model 50 Analyzer is ideal for measuring low levels of CO in ambient air such as in rooms and garages, or around registers, furnaces, stoves, water heaters, and other types of combustion appliances. The Snifit samples the surrounding air and shows the detected concentration of CO on its Liquid

Crystal Display. The Snifit is not intended to be used in flue gases or in temperatures exceeding 104 °F (40 °C).

Features

• Measures and displays 0 to 1999 ppm CO in room air

• Sensitive CO sensor will last up to 2 years

• Backlight for viewing in dark areas

• Compact pocket size

• Low battery indication

• Manual zero adjust

• Factory calibrated on 100 ppm CO

• Simple field calibration

• Auto power-off after 35 minutes

• Single 9V battery (included) provides at least

1500 hours of operation

Bacharach, Inc.

621 Hunt Valley Circle, New Kensington, PA 15068

Ph: 724-334-5000 • Fax: 724-334-5001 • Toll Free: 800-736-4666

Website: www.bacharach-inc.com • E-mail: [email protected]

Printed in U.S.A.

® Registered trademarks

Specifications

Gas Monitored ............ Carbon Monoxide (CO)

Range .......................... 0 to 1999 ppm

Resolution ................... 1 ppm

Accuracy ...................... ± (5% of reading + 5 ppm)

Response .....................

≤ 30 sec. to 90% of final value

Power ........................... 9V battery

Battery Life ................ 1500 hours minimum

Temperature Range .... 32 to 104 °F (0 to 40 °C)

Case Material ............. High impact plastic

Weight ......................... 0.25 lb (0.11 kg) without battery

Dimensions ................. 5.5" L x 2.0" W x 1.6" H

(140 x 51 x 41 mm)

Operation

Turning the Snifit

On/Off

If not already done, install a 9V battery as described under

Battery Installation.

Turn on the instrument by pressing its

Power On button.

Turn it off by pressing

Power Off (or the instrument will automatically shut itself off after approximately 35 minutes).

Z E R O

A D J U S T

L O W

B A T T E R Y

I N D I C A T I O N

B A C K L I G H T

O N / O F F

S n i f i t

C A R B O N

M O N O X I D E A N A L Y Z E R m o d e l 5 0

L O B A T

S p a n A d j u s t

B a c k l i g h t O f f - P o w e r O n p p m C O

Figure 1. Snifit 50

S P A N

A D J U S T

P O T .

D I S P L A Y

P O W E R O N

P O W E R O F F

Zeroing the Sensor

Turn on the Snifit and allow the displayed reading to stabilize before proceeding – approximately 30 seconds. Then with the instrument sampling fresh air

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(air that is free of CO), adjust the Zero Adjust knob at the top of the instrument for a reading of 0 ±1 ppm.

If you’re not sure about the quality of the surrounding air, you can apply a blend of Oxygen/Nitrogen gas to the sensor as described under Calibration.

Checking for CO

Important! Ensure that the sensor grille at the rear of the instrument is unobstructed and open to the atmosphere. A quick instrument check can be performed by allowing the smoke of a blown-out match to enter into the sensor grille. This should cause the indicated CO level to increase.

After zeroing the Snifit, simply hold the instrument in the area that you suspect the presence of CO gas. If

CO is present, the instrument will indicate the concentration of CO in ppm on its display.

Backlight

Pressing the Backlight button will illuminate the display for a period of 8 minutes, or until it is manually turned off by again pressing the Backlight button.

Overrange

If the CO level exceeds 1999 ppm, the displayed reading is replaced by the number “1”.

Low Battery

When the Snifit’s 9V battery is nearing the end of its useful life,

LO BAT will appear in the upper left

L O B A T hand corner of the display. Although you can continue using the instrument under this condition, you should replace the battery as soon as possible to ensure accurate CO readings.

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P U S H C A L I B R A T I O N C U P

O V E R S E N S O R H O U S I N G

P a r t s S h o w n :

1 . C O S p a n G a s C y l i n d e r , 5 1 - 1 9 9 4

2 . R e g u l a t o r , 0 3 - 4 3 1 8 *

3 . T u b i n g , 0 3 - 6 3 5 1 *

4 . F l o w m e t e r , 0 6 - 6 1 6 3 *

5 . C a l i b r a t i o n C u p A s s e m b l y , 2 3 - 2 1 5 6 * *

* P a r t o f C a l i b r a t i o n K i t 2 4 - 7 0 5 9

* * P a r t o f T o o l / C u p K i t 1 9 - 3 2 4 2

Figure 2. Calibration Equipment Setup

Calibration

Important! For accurate Snifit operation, periodic calibration of its CO sensor is required.

To calibrate the CO sensor, you will need the equipment listed under Accessories. Note that the Zero Gas

Cylinder is needed only if you’re unsure about the quality of the surrounding air for zeroing purposes.

Calibrate the sensor to a known concentration of CO gas as follows:

1. Assemble the calibration equipment per Figure 2.

2. Zero the instrument as previously described under

Zeroing the Sensor.

If necessary, you can use the calibration cup to apply a blend of Oxygen/Nitrogen gas directly over the sensor by attaching a zero gas cylinder to the regulator and adjusting the regulator knob for a flow rate of 2 SCFH.

3. Push the Calibration Cup over the sensor housing.

4. Attach a CO Span Gas Cylinder to the regulator.

Then apply span gas to the sensor by adjusting the regulator knob for a flow rate of 2 SCFH.

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5. Allow span gas to flow until the displayed reading stabilizes – approx. 3 minutes. Then, using Calibration Tool 06-9453 (supplied in Calibration Tool /

Cup Kit 19-3242), turn the Span Adjust potentiometer until the displayed reading matches the concentration stamped on the Span Gas Cylinder.

6. Calibration is now complete. Turn off the Regulator and remove the calibration equipment.

Maintenance

Battery Installation

Remove the slotted screw from the rear of instrument; then lift off the front case.

Install a 9V Alkaline battery

(Duracell MN1604 or equiv.) in the location shown in Figure 3; then reinstall the front case.

Figure 3. Battery

Location

Sensor Replacement

The sensor needs replaced when it can no longer be calibrated to the Span Gas Cylinder value using the

Span Adjust potentiometer.

1. See Figure 4. Remove the screw from the rear of the instrument; then lift off the front case and remove the printed circuit board assembly.

2. Unplug the old sensor and dispose of it properly.

3. Inspect the sensor gasket and filter. Replace an item if is torn, deformed, or contaminated with dirt.

4. Remove the wire-jumper from the pins of the new sensor; plug in the sensor; then reassemble the instrument.

5. Calibrate the new sensor.

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C O

S E N S O R

F I L T E R

G A S K E T

W A R N I N G !

R e m o v e j u m p e r - w i r e f r o m p i n s b e f o r e i n s t a l l a t i o n

Figure 4. Sensor Installation

Replacement Parts

Item Part No.

CO Sensor .......................................................... 19-7061

Gasket ................................................................ 19-3234

Filter .................................................................. 19-3244

Accessories

Item Part No.

Calibration Kit .................................................. 24-7059

Calibration Tool / Cup Kit ................................ 19-3242

Span Gas Cylinder, 100 ppm CO in air ........... 51-1994

Zero Gas Cylinder, 20.9% O

2

in Nitrogen ....... 51-7131

Bacharach Service Center

Replacement parts and accessories can be obtained by contacting the following Bacharach Service Center:

Bacharach, Inc.

625 Alpha Drive

Pittsburgh, PA 15238

Phone: (412) 963-2214

FAX: (412) 963-2606

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