Brochure

T775 SERIES 2000 ELECTRONIC STAND-ALONE CONTROLLERS
15 63-7147—3
Hot Water Reset (continued)
Wiring
All output relays should have a common power wiring source,
which may or may not be the same as the T775 power wiring.
Fig. 13. T775R WirIng - Hot Water Reset.
Device Checkout
The T775 performance can be checked out to determine if
proper operation exists.
For example, when the outside air temperature is at 50° F
(10° C), the boiler setpoint temperature should be 180° F
(82° C). See Fig. 14. Use the alternate Home screens to
check that the effective setpoint is adjusting correctly based
on the outside air temperature (sensor B).
NOTE: The alternate Home screens do not show live
updates of the sensor temperature. They show the
temperature only at the moment the button is
pressed.
1. From the Home screen, use the $ button to verify
the setpoint temperature for each output.
2. Then, press the HOME button to view the actual
outside air temperature (sensor B).
Fig. 14. Boiler Discharge Temperature Setpoint vs.
Outside Temperature.
L1
(HOT)
L2
SENSOR A
(HOT WATER DISCHARGE)
C
NO
NC
C
NO
NC
C
NC
NO
C
NC
NO
T
T
RELAY
1
C
+
RELAY
4
RELAY
3
RELAY
2
T775R
M24872
T
T
SENSOR B
(OUTSIDE AIR)
HOT
WATER
BOILER #2
HOT
WATER
BOILER #1
120
COM
240
POWER WITH 24 VAC OR 120/240 VAC AT THE APPROPRIATE
TERMINAL BLOCK.
24 VAC POWER TERMINAL BLOCK.
1
1
2
120 VAC
2
M24873
BOILER SETPOINT
TEMPERATURE
OUTSIDE AIR
TEMPERATURE
210°
160
170°
180°
190°
20°
70°
60°
50°
40°
30°200°