Use and Care Manual

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Follow the testing method that best describes your installation

problem.

If the previous tests did not solve the issue, check that the

equipment is working.

The testing procedures require

a multimeter, also known as a

multitester or Volt-Ohm Meter

(VOM). Refer to the multimeter’s

instructions for operation.

This document contains testing procedures for the Common

Maker to determine installation errors and equipment faults.

Equipment: Any furnace, boiler, zone controller, zone valves,

etc, the thermostat is controlling.

Thermostat Cable: The cable in the wall that connects the

thermostat to the equipment. Contains two or more wires.

Thermostat Subbase: The component attached to the wall

that the thermostat fits onto. Contains the connections to the

thermostat cable wires.

Open Circuit: A break in a wire that prevents electricity from

flowing through it.

Short Circuit: An unintended

connection between two or

more wires in the thermostat

cable, or between a wire and

electrical ground.

Common Terms

Overview

Needed Tools

Installation Testing

Equipment Testing

No Power at Thermostat

Common Maker Test

Equipment Will Not Start

Thermostat Cable Test

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The thermostat is not powering on

Determine if the Common Maker is faulty

The thermostat has power but the equipment will not start

Determine if the thermostat cable is damaged

Common Maker

Troubleshooting

Multimeter

00.0

DIGITAL

MULTIMETER

Summary of content (6 pages)

PAGE 1
Common Maker Troubleshooting Overview This document contains testing procedures for the Common Maker to determine installation errors and equipment faults. Common Terms Equipment: Any furnace, boiler, zone controller, zone valves, etc, the thermostat is controlling. Thermostat Cable: The cable in the wall that connects the thermostat to the equipment. Contains two or more wires. Thermostat Subbase: The component attached to the wall that the thermostat fits onto.
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A No Power at Thermostat Troubleshooting Problem: The Common Maker and thermostat are installed but the thermostat is not receiving power. 1. Remove the thermostat from its subbase. Set the multimeter to ‘Volts AC’ (V~) and measure between the subbase ‘R’ (or ‘Rc’) and ‘C’ terminals. It should read between 23-28 volts. If the multimeter reads 0 volts • The power to the equipment should have been turned off during installation. Ensure it was turned back on. • Check each wire nut for broken wires.
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B Equipment Will Not Start Troubleshooting Problem: The Common Maker and thermostat are installed, the thermostat has power, but the equipment will not start. 1. Check that the thermostat cable wires were not crossed during installation. This may occur when both thermostat cable wires are the same color or when a spliced thermostat cables has different colored wires at the thermostat and equipment.
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D Common Maker Test (Equipment Transformer) Troubleshooting Problem: The Common Maker and thermostat are installed, the thermostat is receiving power, and the ‘Equipment Will Not Start’ section did not resolve the issue. This test will determine if there is a fault in the Common Maker. It can be tested either at the equipment transformer (page 5) or a bench power supply (page 6). Testing at Equipment Transformer 1. Disconnect the Sender, Receiver, and thermostat cable from the equipment. 2.
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D Common Maker Test (Bench Power Supply) Troubleshooting Problem: The Common Maker and thermostat are installed, the thermostat is receiving power, and the ‘Equipment Will Not Start’ section did not resolve the issue. This test will determine if there is a fault in the Common Maker. It can be tested either at the equipment (page 5) or a bench power supply (page 6). Testing at Bench Power Supply 1. Set the multimeter to ‘Resistance’ (Ω) and connect it to the Receiver’s red and white wires.
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C Thermostat Cable Test Troubleshooting Problem: The Common Maker and thermostat are installed, the thermostat is not receiving power, and the ‘No Power at Thermostat’ section did not resolve the issue. This test will determine if there is a fault in the thermostat cable. Voltage Test 1. Disconnect the thermostat cable wires from the thermostat and equipment. Separate the wires so they are not making contact with anything.