Replacing old 2-wire spring damper with a high quality ecojay damper

UPDATE: March 2017 - NEW Dampers available now.  TAKE-OFF ROUND, INSERT ROUND & RECTANGLE Dampers all available now ... scroll down to see all damper models. OR click here.

Some older zone control panels have only two connectors for damper wiring (common & power-close).  These were designed when predominately 2-wire (spring open) dampers were used for zoning.  In recent years, 3-wire (power-open, power-close) dampers have become more common because of their low power consumption and higher reliability.  You might think you have to upgrade your zoning panel to accommodate for these preferable 3-wire dampers... not with Ecojay dampers and belimo actuators.  The wiring diagram below shows how to connect the Ecojay Power Damper to an older zone panel that is only designed to work with 2-wire dampers.

If you are planing to replace the zone controller with SmartZone, this diagram is NOT necessary.

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If you have any questions, call or email us.

What type of damper is best Spring or Power?

Damper Type Selection

There are two basic types of dampers available in mass today.  Although, there are other damper types such a “balloon” type and pneumatic controlled dampers (used more commonly on DDC systems not included), for this context we will discuss these two main types of dampers:

• Spring Open or Close (Spring Damper)

• Power Open & Power Close (Power Damper)

Power Dampers

Power Open /Power Close dampers use three wires to either power open or power close.   They zone panel is responsible for supplying a 24VAC signal to either the PO (Power Open) or PC (Power Closed) terminal of these dampers.  This type of damper was traditionally reserved for “higher-end” or commercial applications because of the cost.  In recent years, however, motor prices have decreased and power dampers have become much more affordable (often no more expensive than the spring equivalent especially when labor and reliability are factored in.)  Primary advantages of Power Dampers include lower power consumption, quiet operation and more reliable parts.  Given the choice, Power Dampers, are almost always preferable.  The only exception to this is when code requires Spring Dampers.

PRO-Grade Power Zone Damper (Round)

from $99.99

Diameter:

Select Diameter 4"5"6"7"8"9"10"12"14"16"18"

4" 5" 6" 7" 8" 9" 10" 12" 14" 16" 18"

Quantity:

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Spring Dampers

The way Spring Dampers work is they have a motor that, when energized by the zoning panel, it closes the damper.  When the damper is ready to open, the motor stops powering the damper closed and a spring opens the damper blade back up.  Spring Dampers have been used in an “economy” application for many years.  The two primary advantages of a Spring Damper are: 1. If the system loses power they “fail” open… but if the system loses power, the equipment isn’t going to be running either and therefore will not matter in MOST cases.  2. They only require two wires for operation.  One of the negative arguments against Spring Dampers has historically been reliability.  This mostly a result of one of its benefits… the cost.  The inherent lifecycle of any spring actuated mechanism (even if it is in the millions) is less reliable than a system that doesn’t include this potential failure point.   In addition to this, the motor that is used has to be a very specific model that allows for running backwards without damage yet still has to be powerful enough to overcome the spring trying to pull the blade in the opposite direction.  This leads to probably the BIGGEST downfall of using a Spring Damper - the power consumption.  Most Spring Dampers on the market use 3 to 4 times the power of the equivalent Power Damper (10-12 VA vs. 2-3VA).  This could be the difference in using a standard sized transformer and having to go to a very large (and expensive) over-sized transformer.   In summary: spring dampers are NOT recommended unless absolutely necessary for some reason.

Spring Zone Damper

from $99.99

DIAMETER:

Select DIAMETER 4" - $99.995" - $99.996" - $104.997" - $109.998" - $109.999" - $129.9910" - $139.9912" - $149.9914" - $159.9916" - $179.99

4" - $99.99 5" - $99.99 6" - $104.99 7" - $109.99 8" - $109.99 9" - $129.99 10" - $139.99 12" - $149.99 14" - $159.99 16" - $179.99

SPRING DIRECTION:

Select SPRING DIRECTION OPENCLOSE

OPEN CLOSE

Quantity:

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The parts that make an HVAC Zoning System

Elements of Zoning

A Zoning System consists of 4 primary pieces:

1. Thermostats

2. Zoning Control Panel

3. Dampers

4. Equipment

1. Thermostats

Thermostats are used in just the same way that a typical thermostat is used except with a zoning system there is ONE thermostat located in each area or “zone.”  Instead of connecting these thermostats to the equipment like a typical application, with zoning all the thermostats are connected to the Zoning Panel.  Suggest purchasing on Amazon.com or from wherever 24VAC thermostats are sold.

2. Zoning Control Panel

sale

SmartZone-4X

Sale Price:$229.99 Original Price:$299.00

The Zoning Panel is the “brains” of the operation.  This computer-like electronic board, reads the calls from all the thermostats and makes decisions about what to energize on the equipment (heat, cool or fan) AND which dampers to open or close.  Zoning Control Panels come in MANY shapes, sizes, and colors but with SmartZone you are just selecting the number of zones)

3. Dampers

PRO-Grade Power Zone Damper (Round)

from $99.99

Not only are the thermostats connected to the Zoning Panel but so are the dampers.  A damper is to airflow in the duct like a faucet is to water in a pipe.  In other words, the damper acts like a valve in the duct system to divert air to the zones where it is needed.

4. Equipment

Finally, the Equipment is also connected to the Zoning Panel.  The equipment refers to the heating and cooling (HVAC) unit.  This can come in many shapes, sizes, and configurations.  In order to apply zoning to any equipment, the correct zoning Panel mush be chosen.  Some Zone Panels are very specific and can only be used with certain types of equipment while some are much more versatile and can be used on almost ANY type of equipment used.

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The above four parts make up the pieces of a Zoning System, but since in a standard system you already have two of these parts (THERMOSTAT and EQUIPMENT).  The addition of a zoning system really consists of adding only two different parts, a ZONING PANEL and DAMPERS.   This makes zoning one of the easiest and affordable ways to gain the much desired improvement of comfort and efficiency.  With these parts installed properly a user can enjoy the ability for both added comfort and increased energy savings.

2, 3, or 4 Zone KITS

from $599.00

# of Zones:

Select # of Zones 2 Zone3 Zone4 Zone

2 Zone 3 Zone 4 Zone

Damper Sizes:

Select Damper Sizes 4" - 10"12" - 16"

4" - 10" 12" - 16"

Bypass:

Select Bypass BasicElectronic

Basic Electronic

Quantity:

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What size dampers do I need?

Damper Size Selection

Typically in an existing install, the duct size will determine the damper sizes needed.  But if starting with a new duct system 2 variables must be known to determine damper sizes.

• Total CFM of System

Calculate using the “whole house load” with maximum diversity.

• Zone CMF (needed for each Zone)

 Total the rooms associated with each zone separately to get the “Zone CFM” (No diversity)

Round Damper Sizes

Round damper sizes range from 4” to 18” typically in 1” increments up to 10” and in 2” increments up to 18”.  There are two numbers that must be used when designing a zoning system with regard to all dampers.  

1. Design CFM – Used to properly size the dampers based on a maximum FPM air velocity at the register to avoid air noise and still provide enough throw to heat or cool the space.  (Typical acceptable FPM 600 to 800)

2. Max CFM – The maximum amount of air that might move through a damper if it is the only zone open.  This assumes the pressure relief is also sized properly (see Pressure Relief below).  This will result in more air noise but must be kept at an acceptable level (no more than 900 FPM).

The chart shows the recommended round damper sizes to be uses for Design and Max CFM. 

NOTE: These are rough estimates & other duct restriction variables could affect the size damper needed.  Consult an HVAC professional if you are unsure.