EngA G-TRAC 1.1, Installation, Operation And Maintenance Manual

A

G-TRAC MANUAL 

IOM-24 

Page 1 

March 1999 R1

A 

G-TRAC 

CONTROL FOR MODULATING DG UNITS 

If you note any errors, omissions, or items that require further clarification, please contact Wade Pascoe at 
(403) 287-4775 or Fax (403) 287-4799 or (403) 243-5059. 

To ensure warranty is honoured, only a qualified HVAC service person or gas fitter that has received training 
on the G-TRAC, should be employed for service and troubleshooting. If information is required please contact 
the nearest Engineered Air office. 

If conversion of degrees F to C is wanted, refer to table on page 4. 

I.  PURPOSE 

The 

G-TRAC

 is designed to provide an accurate method of temperature control by modulating the size of the 

flame on the DG Series heaters. It has been designed to operate with a variety of discharge control devices 
and has the ability to utilize a room sensor for set point override control. The usual controls being applied to 
the 

G-TRAC

 are arranged to Johnson Controls TE 6000/TE 6100 series or the 

G-TRAC

 is being operated as 

a slave to the CTRAC. It is often applied to Gordon Piatt or Maxon Burner Systems. 

II.  CAUTION 

The 

G-TRAC

 has a number of internal potentiometers. These are set up at the factory. These potentiometers 

should not be field adjusted unless consultation has been made with someone who is familiar with the control. 
Tampering may misalign the control operation resulting in poor combustion and/or poor temperature control or 
calibration. 

III. SIMPLIFIED OPERATION 



24 V power to terminals "H" and "N" 



36 seconds later terminals "SA" and "SA" make to start supply fan if the heat switch is not “on”. 

NOTE

: 

If the heat switch is already "on" there may be a further delay before the supply 
blower starts while the heat starts. 



Closing the remote heat switch places 24 V power to "HS" 

(heat switch)

. 



If there is a call for heat from the temperature control device attached to the G-TRAC: 

-

As a safety procedure, the G-TRAC checks if "AS" is closed before the combustion blower starts. If it 
is, then "CB" contacts will not close to start the combustion blower due to a closed air switch. 

-

If “AS” is open then "CB" to "CB" will close to start the combustion burner motor. Pre-purge is factory 
set between 1 and 8 minutes. The length of pre-purge time is determined by the size of the heat 
exchanger. 

(Jumper selection listed in Section XIV about replacing the G-TRAC.)

-

The combustion blower moves air into the combustion chamber and the airflow closes the air switch 
putting 24 volts on G-TRAC terminal "AS" 

(air switch)

. 

-

After pre-purge is complete "FR" to "FR" 

(flame relay)

 closes to power the flame relay for an ignition 

attempt. 

-

If the supply blower had been shut off, "SA" to "SA" will close again 36 seconds after the pre-purge is 
done to re-start the supply air fan. This is to allow for heat exchanger warm-up.