Table Of Contents - Honeywell T775 Series 2000 Application Manual

T775 SERIES 2000 ELECTRONIC STAND-ALONE CONTROLLERS
IMPORTANT
The T775R is an operating control, not a limit or safety control. If used in applications requiring safety or limit controls, a
separate safety or limit control device is required.

TABLE OF CONTENTS

T775 Application Tips .............................................. 3
Compatible Components......................................... 3
Temperature Sensors................................................. 3
Humidity Sensors (T775U only) ................................. 3
Low Differential Pressure Sensors (T775U only) ....... 3
Universal Sensors (T775U only) ................................ 3
Accessories................................................................ 4
Features .................................................................... 4
T775 Operations ....................................................... 6
Integral Action ............................................................ 6
Derivative Action ........................................................ 6
Differential vs. Throttling Range................................. 6
Setpoint High Limit ..................................................... 6
Reset Programming
(T775L, T775P, T775R, and T775U models only)...... 7
T775 Applications .................................................... 8
Water Source Heat Pump Loop
Water Controller - T775B ......................................... 8
Chiller - T775B .......................................................... 9
Chiller, Rotary Compressor - T775B ....................... 10
Cooling Tower Control - T775B2040 ........................11
Time-based Control of Fan,
Pump, etc. - T775 (all models) .............................. 12
Damper or Valve Modulation - T775M or T775R..... 13
Hot Water Reset - T775R........................................ 14
Chilled Water Reset - T775R .................................. 16
Multi-Stage Boiler Control (No Reset) - T775P ....... 17
63-7147-05
Multi-Stage Boiler Control (Reset) - T775P ............. 18
Multi-Stage Chiller Control (No Reset) - T775P....... 20
4 Stage with Pump Output and Reset -
T775P using a T775S Expansion Module ................ 21
4 Stage with Pump Output and Reset (continued) ... 22
3 Stage Reciprocating Chiller - T775L ..................... 23
4 Stage Heat and 6 Stage Cool - T775L .................. 24
4 Stage Heat and 6 Stage Cool (continued) ............. 25
Pressure with a Variable
Frequency Drive (VFD) - T775U.............................. 26
Carbon Dioxide (CO2) Sensing - T775U ................. 27
Resetting Zone Air Temp Based on
Outside Air Temp (2 stage cooling) .......................... 28
Resetting Discharge Air Temp Based
on Return Air Temp (Modulating cooling valve)........ 29
Using the T775R as a Differential
Temperature Controller for Solar Water Heating ...... 30
Maintaining Differential Temperature
for both Heating and Cooling.................................... 32
T775 Application Replacement Examples 33
T775M2030 Replacement for W973A Logic Panel .. 33
T775R Replacement for W964F Aquatrol
Panel with Floating Actuator..................................... 35
T775L Replacement for S984 Step Controller.......... 38
T775L Replacement for W7100C
Discharge Air Controller ........................................... 41
T775 Cross Reference............................................ 44
Notes........................................................................ 55
2