User Guide

Taco Radiant Made Easy Application Guide
Variable Speed Outdoor Reset “00” Circulator (00-VR)
OVERVIEW
Variable Speed Outdoor Reset “00” Circulator (00-VR)
The 00-VR is a microprocessor-based variable speed circulator
designed to regulate the supply water temperature to a heating
system based on a reset ratio, so that the heat supplied to the
building or zone equals the heat lost by the building. A full featured
outdoor reset control is built right on board the circulator. All sen-
sor, low voltage and line voltage connections are made directly to
the circulator. The 00-VR modulates its speed to inject hot water
from the boiler loop into the radiant or reduced temperature loop
while providing Outdoor Reset to a heating system. Available in
any style 003-0014, the 00-VR also comes with a boiler sensor to protect the boiler against low return temperatures.The
00-VR circulator is the ultimate for protection, control, ease of installation, and trouble free operation.
CONTROL STRATEGY
Outdoor Reset
In order to properly control a hot water heating system, the
heat supplied to the building must equal the heat lost by the
building.
• The heat supplied to the building is directly proportional to
the temperature of the water and the surface area of the
heating element. The higher the temperature of the water
flowing through the heating terminal, the higher the heat
output.
• The heat lost from a building is dependent on the outdoor
temperature.As the outdoor temperature drops, the building
heat loss increases.
These two facts lead to the concept of outdoor reset, based on a
reset ratio, which increases the supply water temperature as the
outdoor temperature drops. Using this approach, the heat lost
from the building is matched by the heat provided by the termi-
nal units, therefore providing more comfort and energy savings.
Features:
•Available in all styles of 003-0014
• All-in-one pump / control
•LED status panel
• Sensors included
• Easy to wire
•ULapproved
• Snap-in PC board
• Fuse protected
• Plug-in low voltage wiring terminal
• Optional integral flow check
• Adjustable heating curve (0.2 to 2.2)
• Selectable maximum supply temperature
(110°F, 130°F, 150°F or OFF)
• Selectable minimum boiler return
temperature (120°F, 135°F or OFF)
•Minimum supply temperature (85°F or
OFF – default to heating curve)
•System and / or boiler pump contact
(line voltage, 5 amp max.)
•Pump exercise (10 seconds after 3 days
of no operation)
•Post purge (20 seconds)
• Fail safe mode (assumes outdoor
temperature of 32°F)
•2 second start delay prevents short cycling
Supply
Sensor
Outdoor
Sensor
Va riable Speed Injection Mixing
Boiler
Sensor
00-VR
EFFECTIVE: March 1, 2004 SUPERSEDES: New
Products & Applications
PA03
Outdoor air temperature
Supply water temperature
50
(10)
30
(-1)
10
(-12)
-10°F
(-23)°C
11 0
(43)
70
(21)
70
(21)
90
(32)
210
(99)
170
(77)
150
(65)
130
(54)
190
(88)
2.2
2.0
1.6
0.8
1.0
0.6
90
(32)
50°F
(10)°C
1.2
0.2
0.4
1.4
1.8
00-VR