EngA C-TRAC2

A C-TRAC2.1 MANUAL
Page viii March 1999 R1
QUICK CHECK FOR C-TRAC-2.1 NORMAL OPERATING SEQUENCE
The following is a flowchart covering many general operating/troubleshooting stiuations.
If a more detailed manual is needed, contact the nearest EngA factory.
 Power OFF then on to 24 VAC to H and N
 Dip switch 1 ‘ON’ only. (removes all overides)
Heat light should come ‘ON’
Is C-TRAC-2 calling for heat? More
than 2 VDC on “HT and B”
YES NO
 If call is for cooling, heat light should
eventually go off (may take 30 min)
 B and HT = 0 VDC
 Is cooling light on?
YES NO
Controller is in mechanical cooling mode.
Is compressor ambient light on?
YES NO
 If heat light ‘ON’, 2 – 10 VDC on B and HT
is modulating signal
 If <1 VDC heat is not being called on
 Economizer will be at minimum position
(min. position is adjusted at pot 7)
Compressors should cycle
on as called for.
YES NO
Is internal time delay light on?
YES NO
Normal operation Outside temperature is
below L.A.C. set point
Check pressure controls on refrigeration circuits
and other safeties. Is 24 V on C and does it pass
thru C-TRAC stages 1 to 5 (contacts closed)
 Neither heat or cool light on - Unit is in free
cooling mode ‘B’ and ‘ED’ = 0-10 VDC. Mix box
modulates

Is internal time delay light on?
NO YES
Cooling stages should cycle on
(as required)
YES NO
Check cooling
safety switches
Internal delay
light ON/OFF
Unit is in its control dead
band and is satisfied
RE: INTERNAL TIME DELAY LIGHT
 If OFF, control is satisfied. Will not change
output.
 If ON, control is not satisfied and will increase or
decrease the amount of heat, economizer or
cooling to try and satisfy.
Replace
C-TRAC if
no lights
ever come
on