Emerson E2 Manuel D’Utilisation

The Comfort Alert diagnostic alarms are configurable 

in the E2 as Disabled, Failure, Alarm, or Notice with an 
accompanying priority setting. All Comfort Alert codes 
will share the same advisory type and priority parameters.

The thermostat does not provide alarming information 

on either high or low temperatures for the Space tempera-
ture sensor. Therefore, the E2 application will provide this 
functionality. 

The thermostat does not provide alarm information on 

a failure of the supply temperature probe (if installed). The 
E2 application will provide this functionality. Advisory 
type, priority, and delay is provided for the supply sensor 
fail advisory.

The E2 application will issue an RTN on an active 

advisory when the corresponding bit of the diagnostic 
code goes to zero. If multiple diagnostic advisories are 
active simultaneously, they will all return to normal when 
the code reads zero.

The RLDS provides for the continuous monitoring of 

refrigerant gas levels in up to 16 separate test zones or 
channels. The instrument is programmed to monitor a 
variety of gases and independent leak (small), spill 
(medium), and evacuation (large) levels may be desig-
nated for each zone. The instrument also retains a log of 

previous readings that can be accessed for analysis.

The RLDS has alarm level configuration parameters 

that are synchronized. These will be read first from the 
device. The E2 will be master of all other parameters. An 
audible alarm and front panel indicators are provided to 
signal alarm and fault conditions, and relay contacts are 
provided that can be used to trigger external alarm devices 
in the event of a system fault, or if a leak (small), spill 
(medium), or evacuation (large) level of gas is detected. 
The system also may be fitted with an optional two-chan-
nel 4-20mA current loop board for connection to remote 
monitoring equipment.

Welded Contactor

Compressor always runs. 

• Compressor contactor has failed closed

• Thermostat demand signal is not connected 

to module.

Welded Contactor

Low Voltage

Control circuit < 17VAC. 

• Control circuit transformer is overloaded

• Low line voltage (contact utility if voltage 

at disconnect is low)

Compressor Low Volt Trip

Protector Trip

Thermostat demand signal Y is 

present, but the compressor is 
not running.

• Compressor protector is open.

• Outdoor unit power disconnect is open.

• Compressor circuit breaker or fuse(s) is 

open.

• Broken wire or connector is not making 

contact.

• High pressure switch open if present in 

system.

• Compressor contactor has failed open.

Protector Trip