4
UCRT INSTALLATION
Do not mount the UCRT junction box on a heat source that exceeds
140oF (60oC). Examples of improper mounting surfaces include vent
pipe, top of heater casing or any place where radiant or convective heat
would cause the junction box temperature to exceed 140oF. The UCRT
is intended for indoor installation only.
Using the key hole slots on the back of the UCRT junction box as a
template, mark 4 holes on the mounting surface, drill pilot holes if nec-
essary, and secure junction box using provided screws.
The Rooftop Inducer includes a 4’ whip and weatherproof junction box.
The PSA-1 must be mounted with the diaphragm in a vertical position.
See Rooftop Inducer instructions for complete installation details.
ELECTRICAL WIRING
FIGURE 8050021
UC1
RT SERIES
UC1 or UCRT
PSA-1
2 WIRE +
GROUND
INSTALLER-SUPPLIED
BURNER INTERLOCK
INSTALLER-SUPPLIED
115 VAC CONNECTION
CONNECTION
T
O
RO
O
F
T
O
P
U
N
IT
3 W
I R
E
+
G
R
O
U
N
D
POWER
REQUIREMENTS
EXTERNAL
POWER SWITCHING
CAPACITY
J1 / J2
JUMPER
SAFETY
CIRCUIT
ADD VENTER MOTOR
LOAD PLUS 1/2 AMP
FOR UC1 LOAD
EXTERNAL
CALL TRIGGER
METHODS
J1 / J2
P1 / P2
L / N
3 TO 4
T-BLOCK
T-BLOCK
(RELAY K1)
XL / XN
UC1 CONTROL
M & MTR
(RELAY K2)
T-BLOCK
A / B
24V
1 / 2
115V
1 / 2
OR
OR
USED TO JUMP CALL HOT (24 VAC) OR CALL LINE (115 VAC) FROM TERMINAL 1 TO TERMINAL 3.
CONNECTED TO FAN PROVER.
1 mA @ 5 VDC. DO NOT SUPPLY POWER HERE.
REMOVE J1-J2 JUMPER IF A DIFFERENT VOLTAGE SOURCE IS PROVIDED TO TERMINAL 3.
120 VAC ±10 %, 50/60 Hz
MOTOR - 1 H.P. MAX. @ 120 VAC, 50/60 Hz
USER-PROVIDED 24 VAC AT TERMINALS 1 & 2. 1 = CALL HOT, 2 = COMMON. CONTROL
REQUIRES 5 mA @ 24 VAC TO TRIGGER. MOVE RED VOLTAGE JUMPER TO "24V" LOCATION.
3 mA @ 5 VDC. MOVE RED VOLTAGE JUMPER TO "DRY" LOCATION. DO NOT SUPPLY POWER.
USER-PROVIDED CONTACT CLOSURE FROM A TO B. SIZE CONTACT CLOSURE TO HANDLE
GENERAL PURPOSE - 15A @ 120 VAC, 50/60 Hz
DURING OPERATION THE CONTROL USES 50 mA MAX @ 120 VAC
MOTOR - 1 H.P. MAX. @ 120 VAC, 50/60 Hz
150 mA MAX @ 120 VAC, 50/60 Hz
CAN ONLY BE CONNECTED TO TJERNLUND-SPECIFIED AUXILIARY DEVICE
CIRCUIT PROTECTION PROVIDED BY INSTALLER
GENERAL PURPOSE - 15A @ 120 VAC, 50/60 Hz
RESISTIVE - 10A @ 28 VDC PILOT DUTY - 470 VA
USER-PROVIDED 115 VAC AT TERMINALS 1 & 2. 1 = CALL LINE, 2 = NEUTRAL. CONTROL
REQUIRES 1 mA @ 115 VAC TO TRIGGER. MOVE RED VOLTAGE JUMPER TO "115V" LOCATION.
D/N 9183006H
ON
PRE-PURGE SETTINGS
(SEE “PRE-PURGE” ON PAGE 3 PRIOR TO SETTING)
1 2
1 2
1 2
1 2
0 Seconds
5 Seconds
20 Seconds
35 Seconds
P1 & P2 PRE-CYCLE FAN PROVER STATUS CHECK
Pre-Cycle
Prover Status
Check Deactivated 9
The Pre-Cycle Prover Status Check is deactivated from the factory on the UCRT. Natural chimney
draft may be sufficient to close the PSA-1 Fan Prover contacts prior to a call for heat which may
cause nuisance lockouts. The Pre-Cycle Prover Status dip switch #9 should be up or “ON” so that
it is deactivated.
ELECTRICAL SPECIFICATIONS
TYPICAL UCRT, PSA-1 FAN PROVER
& ROOFTOP INDUCER INSTALLATION
UCRT
ROOFTOP INDUCER
INCLUDES 4’ WHIP
AND WEATHER-
PROOF BOX
SPEED CONTROL
RED LEAD
TO INDUCER
6 AMPS MAXIMUM @ 120 VAC 50/60 HZ.
