15

Troubleshooting Guide

Symptom

Possible Cause

Remedy

 

 

 

 

 

 

 

 

 

CM901 has a blank LCD

Batteries not installed

Check to see if there are batteries in the battery

screen

 

compartment and the paper tab has been removed

 

 

 

 

 

 

 

 

Incorrect battery orientation

Check that the batteries have been installed in the

 

 

 

 

correctorientation

 

 

 

 

 

 

 

 

 

 

Exhausted batteries

Replace with new batteries

 

 

 

 

 

CM901 shows a flashing

Batteries are exhausted and

Replace with new batteries

 

symbol on the LCD screen

need replacing

 

 

 

 

 

 

 

 

The CM901’s LCD screen

No power to heating system

Check that there is power to the heating system.

works but the heating does

 

 

 

 

 

 

 

 

 

 

 

 

not switch on

Program does not call for

Move the slider switch to MAN and press

or to

 

 

 

heat

increase the temperature a few degrees above the

 

 

 

 

current room temperature. The heating should come

 

 

 

 

on after a few seconds.

 

 

 

 

 

 

 

 

 

CM901 not connected to

Call installer to check electrical connection between

 

 

 

boiler properly

the CM901and the boiler.

 

 

 

 

 

 

Heating switches ON or OFF

CM901 not set correctly for

Call Installer

 

 

too slowly or quickly

your system

 

 

 

 

 

 

 

 

 

 

Temperature swings between

CM901 not set correctly for

Call Installer

 

 

too hot and too cold.

your system

 

 

 

 

 

 

 

 

CM901 shows a flashing

Fault in CM901

Remove and re-insert the batteries in the CM901.

 

 

symbol on the LCD

 

If the

 

 

symbol does not clear itself in a few

screen

 

minutes call the installer

 

 

 

 

 

 

 

 

 

 

Page 15
Image 15
Honeywell CM901 manual Troubleshooting Guide, Symptom Possible Cause Remedy

CM901 specifications

The Honeywell CM901 is a highly efficient, programmable room thermostat designed for residential heating systems. This versatile device caters to the needs of homeowners by combining user-friendly features with advanced technology to ensure optimal climate control in living spaces.

One of the standout features of the CM901 is its ability to offer seven-day programming. Users can set different heating schedules for each day of the week, allowing for flexibility according to their lifestyle. This functionality is particularly beneficial for families with varying routines, enabling energy savings during times when the home is unoccupied. Users can program the thermostat to reduce heating in the mornings when they are away and ramp up the temperature just before they return home.

The CM901 supports a wide range of heating systems, including gas, oil, and electric boilers, as well as underfloor heating systems. This compatibility makes it suitable for a variety of homes and heating setups, ensuring that it can meet the unique needs of different households. Furthermore, its easy installation process allows homeowners or contractors to set it up with minimal hassle.

Equipped with an intuitive interface, the CM901 features a clear LCD display that shows the current room temperature and set point at a glance. The backlit screen enhances usability, enabling users to read the display in low-light conditions. The device also allows for manual override, making it convenient for users to adjust settings on-the-fly without interfering with their programmed schedule.

Energy efficiency is a prime focus of the CM901, as it helps reduce heating costs while maintaining comfort. Its precise temperature control and programming capabilities ensure that heating is only used when necessary, leading to reduced energy consumption. This not only benefits the environment but also helps homeowners save money on their energy bills.

In terms of build quality, the Honeywell CM901 boasts a sleek and modern design that fits seamlessly into contemporary home decor. Its durable construction ensures longevity, offering reliable service for years to come.

Overall, the Honeywell CM901 stands out as a practical solution for homeowners seeking a blend of comfort, efficiency, and ease of use in their heating systems. With its programmable features, adaptability, and user-friendly interface, the CM901 is an excellent choice for those looking to enhance their indoor climate control experience.