ULTRA HIGH EFFICIENCY POWER VENT/POWER DIRECT VENT - SERVICE MANUAL

UIM (CONT)

Table 5 - Operational States (Modes)

STATE

DESCRIPTION

 

 

 

The water heater is not in an active heating cycle. This usually means the temperature

Standby

in the tank has reached Operating Set Point and has not dropped low enough to initiate

 

a call for heat.

 

 

 

The control system is waiting for specific conditions to occur (primarily pressure switch

Input Verification

normal state verification - see page 20) before the unit can continue in the Sequence of

 

Operation.

 

The blower has been energized - the control system is purging out any excess gas or

Pre-Purge

left over products of combustion from the heat exchanger at the beginning of each

 

heating cycle.

 

 

Igniter Warmup

The igniter has been energized and is currently warming up to ensure proper ignition -

typically last 17-20 seconds.

 

 

 

Ignition Activation

The control system is allowing for a steady burner flame to be established. Duration of

this and the Ignition Verification state is typically 4-6 seconds.

 

Ignition Verification

Assurance of proper flame sense is being determined.

Inter-Purge

After a failed trial for ignition the control system is purging out any excess gas or left

over products of combustion from the heat exchanger before another trail for ignition.

 

 

 

Heating

Burner flame has been properly established - minimum flame sensing current has

been verified by the control system - water in the tank is being heated.

 

Post-Purge

The control system is purging out any excess gas or left over products of combustion

from the heat exchanger after a successful heating cycle.

 

 

 

 

The control system has detected a fault and declared a fault condition. The control

Fault

system is locked out. A fault message is displayed on the UIM (page 27). The problem

that caused the lock out must be corrected before the water heater can resume a

 

 

heating cycle.

 

 

Technical Literature Department

31 of 52

Ashland City, TN © 2008

Servicing should only be performed by a Qualified Service Agent

 

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State Industries GP650HTPDT, SHE50-100PE, SHE50-100NE manual Operational States Modes, State Description