Tjernlund HSJ, 1, 2 Series with UC1 Universal Control (Version X.06) 8504106 Rev C 07/05 User Manual
Page 7

UC1 UNIVERSAL CONTROL BOARD FEATURES
# 1.
Power supplied by board. Do not supply power to this area or control damage may result.
# 2.
Do not supply power to the appliance interlock block with the call selector in the “DRY” position. 
Control damage may result if power is supplied.
# 3.
Circuit protection must be provided by the installer. 16 Amps is the maximum current allowed for this device at terminal L. 
A 15 Amp circuit breaker is recommended.
VET
I
I
LED STATUS & FAULT INDICATORS
LED INDICATOR LIGHTS 
LED #1 (Amber) 
Appliance call for heat.
LED #2 (Blue)
Safety circuit through P1 & P2 (Venter Fan Prover). Indicates Venter prover is closed during run cycle. 
Burner circuit is energized with Interlock Relay contact closure from terminal 3 to 4. 
LED #3 (Green)
Power switched to Venter motor from L to MTR & M.
LED #4 (Red)
Status / Fault indicator.
LED #5 (Red)
Used as a status indicator.
LED #6 (Red)
115 VAC power supplied to board.
LED STATUS INDICATORS
LED #4 & #5 (Red) Flashing Alternately = Venter in Pre-purge. (Pre-Purge options 0, 5, 20, 35 seconds)
LED #4 & #5 (Red) Flashing in Unison = Venter in Post-Purge. (Post-Purge options 0, 30 seconds or 1, 2, 4, 8, 16 minutes)
LED #4 (Red) Flashing Continuously*
= Fan Prover opened for more than 10 seconds during burner cycle.
(Venter will run for 10 minutes, attempting to make Fan Prover)
LED #5 (Red) Flashing Intermittently
= With no call for heat, flashes 3 seconds on / 3 seconds off if microcontroller is working properly.
4
LED 1 (AMBER)
LED 2 (BLUE)
LED 3 (GREEN)
LED 4 (RED)
LED 5 (RED)
LED 6 (RED) POWER LED
DRY
24 V
115 V
APPLIANCE
INTERLOCK
RELAY
VENTER
MOTOR
RELAY
A B 1 2 3 4 L N
J1 J2 XL
XN
P1 P2 C GND F
(1 9)
N M MTR
APPLIANCE INTERLOCK
RELAY
1 HP MAX LOAD across 
terminals 3 & 4.
VENTER MOTOR RELAY
1 HP MAX LOAD from 
terminals L to MTR & M.
XL / XN AUXILIARY DEVICE 
POWER TERMINALS 
115 VAC - Maximum of 0.15 Amps.
Only connect to Tjernlund auxiliary devices.
SEE WARNING # 1.
MTR & M / N LOAD TERMINALS 
FROM VENTER MOTOR RELAY
Used to drive Venter Motor. 
1 HP MAX LOAD across terminals MTR & M / N. 
L / N - 115 VAC POWER 
SUPPLY BLOCK
115 VAC / 50-60 Hz
Circuit protection provided by installer.
SEE WARNING # 3.
APPLIANCE INTERLOCK 
TERMINAL BLOCK (A-B, 1-4)
A - B - Dry Contact call. 3 mA @ 5VDC.
SEE WARNING # 1.
1 - 24 or 115 VAC intercepted call.
IMPORTANT: RED voltage jumper must 
match intercepted call voltage.
2 - 24V common or 115V Neutral.
3 - Common terminal to appliance relay con-
tacts. IMPORTANT: J1-J2 jumper routes 
call voltage at terminal 1 to 3. Remove 
J1-J2 jumper if a different voltage source is 
provided to terminal 3.
4 - Normally open terminal of appliance relay.
Will be energized from terminal 3 if safety 
circuit is “proven”. 
J1- J2 CALL
JUMPER
Used when the call signal is
used as the “proven” return
signal to the appliance. See
wiring section for details.
APPLIANCE CALL
VOLTAGE SELECTION
Place RED voltage jumper in
proper location based on
appliance call interlock volt-
age. SEE WARNING # 2.
IMPORTANT
LED STATUS LIGHTS
See “LED Status & Fault
Indicator Section” for details.
DIP SWITCH SETTINGS
Pre-Purge (1-2)
Post-Purge (3-8) 
Prover status check (9)
See “Pre / Post Purge &
Prover Status Check Dip
Switch Settings”. 
P1 - P2 SAFETY CIRCUIT
TERMINALS
1 mA @ 5VDC.
SEE WARNING # 1.
C, GND, F AUXILIARY DEVICE 
COMMUNICATION TERMINALS
2 mA @ 5VDC. For Tjernlund MAC1E or 
MAC4E auxiliary devices. SEE WARNING # 1.
