General Tools DTR900 User Manual

INSIDE-OUTSIDE

THERMOMETER

WITH MIN/MAX MEMORY

USER’S MANUAL

DTR900

Please read this manual carefully

and thoroughly before using this product.

TABLE OF CONTENTS

Introduction . . . . . . . . . . . . . . . . . . . . . . 3 –4

Key Features . . . . . . . . . . . . . . . . . . . . . . . . 4

What’s In the Box . . . . . . . . . . . . . . . . . . . . . 5

Product Overview . . . . . . . . . . . . . . . . . 5 –7

Setup Instructions . . . . . . . . . . . . . . . . 7 – 13

Activate the Unit . . . . . . . . . . . . . . . 7 –8

Choose Your Temperature

Unit & Time and Date Format . . . . 9 – 10

Set the Time and Date . . . . . . . . 11 – 12

Extend and Secure the

External Sensor Cable . . . . . . . . . . . . 13

Operating Instructions . . . . . . . . . . . . 14 – 17

Specifications . . . . . . . . . . . . . . . . . . . . . . 17

Maintenance Tips . . . . . . . . . . . . . . . . . . . 18

Warranty Information . . . . . . . . . . . . 18 – 19

Return for Repair Policy . . . . . . . . . . 19 – 20

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INTRODUCTION

Thank you for purchasing General Tools &
Instruments’ DTR900 Inside-Outside Thermometer
with MIN/MAX Memory. Please read this user’s
manual carefully and thoroughly before using the
product.

The DTR900 is an affordable instrument that is
accurate enough (±1.8°F) for residential or office
monitoring of indoor and remote temperatures. Its
ability to store and recall two sets of maximum and
minimum temperatures—one sensed by the
display unit (installed indoors) and the other
sensed by a probe at the end of a 6.5 ft. (2m) long
cable—makes the DTR900 suitable for household
use or for monitoring the temperature of a
greenhouse or a food market’s walk-in and reach­in refrigeration cases. In a food market, for
example, the display unit could be mounted
outside a refrigeration case and the external
sensor could be placed inside the case. In such an
installation, recalled time- and date-stamped
minimum and maximum temperature readings

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could help the market operator determine the
impact of a power failure on the temperature of
stored food.

The DTR comes in a box along with a non­detachable external sensor-tipped probe, one
“AAA” battery and this user’s manual.

WHAT’S IN THE BOX

The DTR900, including its non-detachable external
temperature probe, is packaged in a box along
with this user’s manual. A single “AAA” battery
with an activation tab is pre-installed in a
compartment accessible from the rear of the unit.

KEY FEATURES

• Simultaneously displays the time and inside and
remote probe temperatures, or the time and date
and the remote probe (outside) temperature

• Stores and recalls minimum and maximum
inside and outside temperatures with time and
date stamps

• Fast response

• Waterproof exterior probe cable is thin enough to
fit under a window

• One switch selects ºF or ºC temperature unit and
time and date format

• Mounts on a wall or a flat surface

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PRODUCT OVERVIEW

Figure 1 shows the front of the DTR900. Note the
three separate liquid-crystal displays within one
window (callout 1), the bundled external cable and
probe (callout 2) and the MIN/MAX (callout 3) and

IN/DATE (callout 4) buttons.

Fig. 1. The DTR900 with
its display window in
“normal” configuration

(showing the time and IN
and OUT temperatures)

햳

햴

햵

5

햷

햶햸

Fig. 2.
The back of
the DTR900
with the battery
compartment
closed

햺

햹

Figure 2 shows the back of the unit with the
battery compartment closed. Note:

• The °F/°C switch (callout 5) at the top of the
case.

• The two hanger holes (callouts 6 and 7) at the
top corners of the case. Use these to wall-mount
the unit.

• The rectangular recess (callout 8) near the
bottom of the case. Use this recess to raise the
unit’s kickstand for mounting on a horizontal
surface.

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햻

• The cutouts (callouts 9 and 10) on the bottom
corners of the case, with the external probe
cable threaded through the left cutout.

SETUP INSTRUCTIONS

ACTIVATE THE UNIT

To begin, remove the plastic film protecting the
display. Holding the unit in your hand with the back
facing you, open the battery compartment by
pushing its cover down (in the direction of the
arrow on it) and away from the unit. Remove the
external sensor cable from the large well of the
compartment so it hangs loosely below the unit,
but do not remove the twist tie keeping the cable
in a bundle.

Note from Fig. 3 that an “AAA” battery (callout 11)
is already installed in the battery compartment.
To extend the battery’s life and to protect the unit
from possible battery leakage during storage, the
unit ships with a plastic tab (callout 12) between
the battery’s anode and the metal plate it connects

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