Automation and Control Solutions
Honeywell International Inc.
Honeywell Limited-Honeywell Limitée
1985 Douglas Drive North
35 Dynamic Drive
Golden Valley, MN 55422
Toronto, Ontario M1V 4Z9
customer.honeywell.com
® U.S. Registered Trademark
© 2006 Honeywell International Inc.
69-1957—1 Rev. 06-06
Boiler is
cold,
house is
cold
Display is ON;
TT-LED is ON
B1 LED is ON
120 Vac at B1-
B2
•
If no, replace control.
•
If yes, check burner
and wiring
Display is ON;
TT-LED is ON
Refer to
err
on
display
—
Boiler is
hot, house
is cold
Display is ON;
TT-LED is ON
C1 LED is ON
120 Vac at C1-
C2
•
120 Vac at C1-C2,
check wiring to pump
•
Wiring ok, is pump
running? If not,
replace the pump.
•
If pump is running,
check for trapped air
or closed zone
valves.
Display is ON;
TT-LED is ON
C1 LED is OFF;
ZC LED is ON
b
Boiler below the
Low Limit
temperature,
wait for boiler to
go above Low
Limit
temperature.
Display is ON;
TT-LED is ON
ZC LED is
OFF
c
Boiler above
LL
? If yes,
check for 120
Vac between ZC
and L2
•
If no 120 Vac,
replace control.
•
If yes, check zone
relays, circulators
and wiring.
Table 3. Troubleshooting Guide
a
.
System
Condition
Diagnostic
Condition
Check
Action
a
. Refer to Fig. 5 for Display and LED locations.
b
. ZC LED ON indicates ZC terminal power is OFF.
c
. ZC LED OFF indicates ZC terminal power is ON.
69-1957-1.fm Page 4 Tuesday, June 20, 2006 11:06 AM
