General Tools General Tools MMH800 Manual

4-IN-1 PIN/PAD RH
MOISTURE METER

USER’S MANUAL

MMH800

99 Washington Street
Melrose, MA 02176

Phone [phone]
Toll Free 1-800-517-8431

Visit us at www.TestEquipmentDepot.com

Please read this manual carefully and thoroughly before using this product.

TABLE OF CONTENTS

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 –3

Key Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

What’s in the Case . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Product Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 –4

Setup Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Install Battery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Operating Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 –6

Measuring Moisture Level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Accounting For Temperature and Humidity . . . . . . . . . . . . . . . . . . . . 6

Checking Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 –8

Maintenance Tips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Warranty Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Return for Repair Policy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

INTRODUCTION

Thank you for purchasing General Tools & Instruments’ MMH800 4-in-1 Pin/Pad RH
Moisture Meter. Please read this user’s manual carefully and thoroughly before using
the meter.

The MMH800 is designed for use in woodworking, water damage restoration, building
construction and home renovation. Examples include:

• Checking for moisture on or below the surface of carpets

• Measuring the surface moisture and/or moisture content of wood, drywall

or concrete before painting, wallpapering, sealing or treating

• Locating water leaks in roofs, floors and walls

• Selecting dry lumber

Because it can measure ambient temperature and humidity in addition to moisture
level, the MMH800 is particularly suitable for water damage restoration projects.

It measures: 1) temperature; 2) relative humidity; 3) moisture level using a pin sensor;
and 4) moisture level using a pad sensor. The meter has both kinds of sensors, with a
pair of pins on top and a split metal pad on the back.

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Which sensor should you use?

It depends on the application. The pad sensor is the only choice for measuring surface
moisture of materials like finished wood, paint or wallpaper that cannot be marred by
pinholes. If measurement accuracy is important, the pin sensor is the better option
because pins can detect moisture below the surface that the pad sensor cannot.

However, for hard materials like wood or concrete, the meter’s readings mostly
represent surface moisture content. For softer materials like soil, paper or powders,
readings are more likely to reflect the average moisture level of the material between
its surface and the penetration depth of the pins.

KEY FEATURES

• Pin (intrusive measurement of moisture content) and pad

(non-intrusive measurement of surface moisture) sensors

• Separate 3-digit displays of moisture level and temperature + humidity

• Selectable wood or building materials measurement mode

• °F/°C switch

• Wide measurement range and high accuracy

• Audible and visual indications of high, medium and low moisture levels

• Holds moisture level readings for convenient viewing later

• Pin cover doubles as calibration checker

• Auto power off function

• Battery charge indicator

WHAT’S IN THE CASE

The MMH800 comes in a custom hard carrying case along with a 9V battery, two pairs
of extra test pins (10mm and 15mm long), and this user’s manual.

PRODUCT OVERVIEW

The figure on the next page shows all of the controls and indicators on the front of the
MMH800, as well as the locations of the sensor and battery compartment on its back.

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