Submittal Sheet

101-057
Add-On Power Controls
Effective: June 1 2000 Supersedes: October 1, 1997
Submittal Data Information
Job: Engineer:
Contractor:
Rep:
ITEM NO. MODEL NO.
Do it Once. Do it Right.
®
TACO INC., 1160 Cranston Street, Cranston, RI 02920 Telephone: [phone] Fax: [phone]
TACO (Canada), Ltd., 6180 Ordan Drive, Mississauga, Ontario L5T 2B3 Telephone: [phone] Fax: [phone]
Visit our website at: www.taco-hvac.com
Printed in USA
Copyright 2007
TACO, Inc.
PC700 & PC702: Boiler Reset Controls
Control: Microprocessor PI Control; This is
not a safety ( limit ) control
Dimensions: 4 3/4” H x 2 7/8” W x 7/8” D
Approvals: CSA NRTL/C; Meets ICES & FCC
regulations for EMI/RFI
Ambient Cond.: Indoor use only
Power Supply: 24 VAC 3VA (Powered by -EXP Control)
Relays: 24 V (ac) 5 A, pilot duty 240 VA
Sensors:
1 Outdoor Air and 1 Supply Water
Boiler Start: 35 to 150°F ( 2 to 66°C )
Outdoor Start: 35 to 85°F ( 2 to 29°C )
Boiler Design: 70 to 220°F ( 21 to 104°C )
Outdoor Design:
-60 to 32°F ( -51 to 0°C )
Boiler Minimum: Off, 80 to 180°F ( 27 to 82°C )
Differential: Auto, 2 to 42°F ( 1 to 24°C )
WWSD: Off, 35 to 100°F ( 2 to 38°C )
Units: °F, °C
PC702 Only:
DHW Demand: 20 to 260 V (ac) 2 VA
Interstage Delay: 0:30 to 4:00 minutes
PC705: Variable Speed Pump Injection
Mixing Control
Control: Microprocessor PID Control;
This is not a safety ( limit ) control
Dimensions: 43/4” H x 2 7/8” W x 1 7/8” D
Approvals: CSA CVS; Meets ICES & FCC
regulations for EMI/RFI
Ambient Cond.: Indoor use only
Power Supply: 24 VAC 3VA (Powered by -EXP Control)
Variable Pump: 120 V (ac) 1.8 A 1/2 hp, fuse 2.5 A 250 V
Relays: 24 V (ac) 5 A, pilot duty 240 VA
Sensors: 1 outdoor air and 2 supply water
Mix Start: 35 to 150°F ( 2 to 66°C )
Outdoor Start: 35 to 85°F ( 2 to 29°C )
Mix Design: 70 to 220°F ( 21 to 104°C )
Outdoor Design: -60 to 32°F ( -51 to 0°C )
Boiler Minimum: Off, 80 to 180°F ( 27 to 82°C )
WWSD: Off, 35 to 100°F ( 2 to 38°C )
Units: °F, °C
Submittal Data Information
Add-On Power Controls
Submittal Data # 101-057
Supersedes: 100-057 Dated: 10/1/97
Effective: 6/1/00
PC700: Boiler Reset Control
The Taco Boiler Reset Control is
a microprocessor-based control
designed to regulate the supply
water temperature from a single
boiler based on the outdoor
temperature. To avoid boiler short
cycling and large temperature
swings, the PC700 is able to contin-
uously adjust the boiler differential.
Standard functions include warm
weather shut down, minimum
boiler supply temperature setting,
and a starting water temperature
setting. The updated Boiler Reset
Control utilizes an easy-to-use
automatic reset ratio calculation to
set the relationship between
outdoor temperature and supply
water temperature (heating curve)
to provide optimum control and
comfort. The control has a liquid
crystal display that clearly shows
the boiler supply temperature as
well as the other monitored
temperatures and settings.
The operation of a hot water
heating system can be improved by
modulating the supply water
temperature as the outdoor
temperature changes. Using this
approach, the heat lost from the
building is matched by the heat
input to the building.
PC702: Two Stage Boiler Reset
Control
The Taco Two Stage Boiler Reset
Control is a microprocessor-based
control designed to regulate the
supply water temperature from
a two stage boiler system based
on the outdoor temperature or
domestic hot water requirements.
The PC702 has all of the features
of the PC700 yet also includes an
adjustable interstage delay setting,
boiler staging using proportional,
integral and derivative (PID) logic,
optional boiler rotation, and a
domestic hot water demand output.
PC705: Variable Speed Pump
Injection Mixing Control
The Taco Mixing Control regulates
the supply water temperature to a
heating system by simultaneously
controlling a boiler and the speed
of an injection pump. Based on
the outdoor air temperature, the
PC705 continuously adjusts the
boiler differential to optimize the
firing cycles of the boiler, prevent
large water temperature swings,
and increase the efficiency of the
system. As the heating load
increases, the Mixing Control
speeds up the injection circulator
and as the load decreases it slows
down the injection circulator.
The updated Mixing Control has
a liquid crystal display that clearly
shows the speed of the variable
speed injection pump. It also
features warm weather shut down,
a maximum supply water tempera-
ture setting, and a boiler sensor
that can be connected in order to
prevent corrosion in the boiler due
to flue gas condensation.
Taco Inc., 1160 Cranston Street, Cranston, RI 02920 / [phone] / Fax [phone]
Taco (Canada) Ltd., 6180 Ordan Drive, Mississauga, Ontario L5T 2B3 / [phone] / Fax [phone]
www.taco-hvac.com