Nailor 35SW - Balancing Airflow Sequence; Dual Duct

IOM-EZVAVINST
Date: 10-2016 Supersedes: 7-2016
Nailor reserves the right to change any information concerning product or specification without notice or obligation.
Page 40 of 48
Installation and Operation Manual
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EZvav Digital Controls
Floangreheat
If the controller is congured for oang reheat, it controls two binary triac outputs to drive the inputs of a tri-state actuator
connected to a valve. If the Reheat loop is less than 30%, the valve is driven closed. If the loop is greater than 70%, the valve is
driven open. If the loop is in between 30% and 70%, no valve acon is taken.
See the topic Floang reheat on page 32 for an applicaon drawing.
Figure8-5 Floangreheatoperaon
BalancingAirowSequence
Balancing airow is the process of calibrang the internal airow sensor to a known standard. In the eld, airow is measured with
an airow hood or other measuring instrument and then compared to the airow measurements from the sensor in the controller.
The balancing process uses an STE-8001W36 or STE-8201W36 as the technicians setup tool for iniang the balancing sequence
and entering actual ow measurements.
When the balancing sequence starts, all other funcons of the controller are locked out.
At the start of the sequence, the controller drives the damper open unl the airow reaches the highest value of either the cooling
or heang maximum airow set points. An airow measurement is made with an airow hood and the actual airow value is
entered into the controller. Once the actual airow is entered, the controller drives the damper closed to the lower value of either
the cooling or heang minimum airow. Another measurement is made with the ow hood and that measurement is entered into
the controller.
Aer the minimum airow measurement is entered, the programming in the controller calculates airow correcon factors which
are used to adjust measurements from the internal airow sensor. Balancing is complete and the controller is returned to normal
operaon.
See the topic Balancing airow on page 24 for the procedure to balance the airow with an STE-8001W36.
DualDuct
A dual duct installaon consists of separate primary heang and cooling ducts, both with control dampers and airow monitoring.
For this type of installaon a EZvav BAC-8007-36 controls the cooling air (primary) damper and a TSP-8001-36 actuator controls
the heang air (secondary) damper.
• As the space temperature rises above the cooling set point, the primary airow is modulated from the Cooling Minimum
ow to the Cooling Maximum Flow.
• As the space temperature falls below the heang set point, the secondary airow is modulated from the Heang
Minimum ow to the Heang Maximum Flow.
• Between the heang and cooling set points, both the primary airow and secondary airow are modulated to maintain
the Dual Duct Minimum airow.
See the topic, Dual duct applicaon on page 33 for an applicaon drawing.
HTG %
DRIVE
OPEN
DRIVE
CLOSED
loop %
0
100
70
Reheat
30
HTG SP
HTG SPAN
-2F
Room temp increase
NO ACTION