FRESH AIR - SmartZone Automatic Contrtol with RANCO ETC Outdoor Temperature Sensor

Fresh Air is important to indoor air quality (IAQ). All the way back to Benjamin Franklin’s “air baths” and even much earlier in history, we have had some at least vague understanding of the fact that “stale” indoor air can be bad for us and we need to get some fresh air at least once in a while.

In modern homes, windows, doors, insulation , house wraps, roofing and other materials have imporved drastically in the last 40 years and we how have homes and buildings that are getting tighter and tighter. This means that the air outside stays out and the air inside stays in... which is good for efficiency of heating and cooling systems, but not for air quality and overall health. This is why many parts of the world have “fresh air” requirements, meaning simply that they are required to bring in a prescribed amount of outside air in and mix it with the inside air. In the US, a standard callled ASHRAE 62.2 is followed as a guideline for how much outside air in CFM (Cubic Feet per Minute) needs to be brought in based on occupancy & square footage of the home/building. We are not here to discuss the efficacy of the 62.2 because it has some obvious flaws in its sheer simplicity, we just want to show how to apply this method of fresh air but with one additional VERY IMPORTANT feature. We want to simply disable the automatic intake of outside air WHEN the outside temperature is too high or too low. What is too high or too low? This is going to depend on your application including climate, hvac equipment type, home size, your comfort level etc.

NOW AVAILABLE - Ecojay custom Outdoor Temperature Controller

The use of the RANCO temperature controller is no longer necessary with the SmartZone. We now offer a custom outdoor temperature controller that provides MUCH more functionality specific to the SmartZone Fresh Air controls.

• High & Low Temperature Limits

• Enable/Disable Fresh Air

• “Demand” Fresh Air

• NEW: Temperature-based Economizer

For more info about this new and exiting product, take a look here:
https://zoningsupply.com/buy/outdoor-air-thermostat

If you are considering Fresh Air or Economizer with your SmartZone-4X, you will want this accessory!

The primary reason for this “ADVANCED FEATURE” is to prevent outside air that is extreemly hot or cold from coming into the house automatically. Use the instructions and diagrams below to install this RANCO ETC-212000 Temperature sensor and you will have the ability to control automatically the temperature range that Fresh Air is allowed to operate. For example , you could set the upper limit to 90 deg F and the lower limit to 30 deg F and then SmartZone will only operate fresh air when the outside temperature is between 30 and 90 deg.

Before this Outdoor Temperature Advanced Fresh Air Feature will work, the SmartZone-4X must be set up for FRESH AIR control. Click the button below to see an application note about basic fresh air. NOTE: Fresh-Air setup instructions can also be found in the SmartZone System Guide

Fresh Air for better Indoor Air Quality

When people think about increasing the Indoor Air Quality of their homes, most probably think about pollutants like smoke/smog or allergens like pollen. Since these originate “outdoors”, the most logical thought is to close up your home as tight as possible and get an air cleaner of some sort. Although air cleaners like filters can and do help reduce the particles in the air to a varying degree, there is MORE to AIR quality than just “cleaning” the air.

The most critical and often overlooked aspect of having good indoor air quality is FRESH AIR. This, in it’s simplest form, is bringing outside air … inside. The first thought of objection might be that it seems counter-intuitive to bring air in that could have pollutants to try and “clean” the air, however, the EPA and other independant studies by AHRAE have shown that the pollutants like pollen can be 2 or 3x as high as outside air if a home is not properly ventilated. (see link below for sources and further explanation)

EPA recommendations for improving Indoor Air Quality: https://www.epa.gov/indoor-air-quality-iaq/improving-indoor-air-quality

A “properly ventilated” house includes both the intake of fresh air and the exhaust of inside air. Most homes come equipped with plenty of exhaust either in the bathrooms or kitchen vent hood but many do not have nearly enough intake of outside air. As a matter of fact, up until the 2000s, most homes were not equipped with any Fresh Air management at all which means that the only outside air that was coming inside was through cracks around doors and window. You might think this was an accident but it was actually “designed” this way because it has been know for 100 plus years that outside air is necessary for a healthy and clean air environment.

SmartZone-4X has a built-in FRESH AIR controller, that can be used to automatically (or manually) bring fresh air into the building. It was designed as a feature to meet the ASHRAE 62.2 standard but has many additional and useful features that make it more desirable than a standard “Fresh Air Control” like the Honeywell W8150.

Shown below, the SmartZone can be used as a “stand-alone” fresh air controller even without the need for any zoning.

Find out more and learn about the Adavanced Fresh Air control features: FRESH AIR - Enthalpy Control

Buy SmartZone-4X for your Fresh Air control

What's a TON got to do with AC?

So you've probably heard of someone refer to an air conditioner's size in terms of  "TONS".  Something like "I got a new 4 TON HVAC unit".  This refers, not to physical size, but to the capacity (ability) of the equipment to generate heat.  That's right, even air conditioning (cooling), is sized by it's ability to produce heat.  In the case of air conditioning, the heat is being "pulled" from inside the house and dispersed outside.  This is why there is always an outdoor component (the air conditioning compressor) when you have AC.

Back to TONs... most people thing of a TON as being 2000 lbs. but with regard to HVAC, a TON is a measurement of heat generation per day.

1 TON of air conditioning is a measure equivalent to the amount of heat necessary to melt 2000 lbs of ice (H20) in a 24 hour period.

But how did we get there? A BTU (British Thermal Unit) is the unit we use express heat energy.  One BTU is equivalent to the amount of heat energy released when burning 1 match all the way. When rating an HVAC unit either for heating or cooling, the amount of BTUs per Hour is often sited.  It has been measured that it takes 143 BTUs to melt 1 lb of ice.  Since, 1 TON of ice is 2000lbs, It will take 2000 x 143 = 286,000 BTUs to melt 1 TON of ice.  The ice could be melted by lighting 286,000 matches all at once or by lighting one at a time... In other words, BTUs only tells us how much heat energy is necessary but not over what time period.  It could melt in 1 minute, 1 hour, or even 1 year depending on how the energy is generated.  So, to rate the output of HVAC equipment, someone decided back in the early 1900s (probably someone at Carrier) that it should be done over a 24 HR peroid (1 day).  This is how we get 286,000 BTUs / 24 hrs =~ 11,917 BTUs per hour or commonly know as 12K BTU/hr is equal to 1 TON.

This means that that 4 TON AC unit you have can melt 8,000 lbs of ICE per day or about the same size block of ice as a Suburban.  That's a lot of heat energy!

ADD-A-WIRE with Zone Control

An ADD-A-WIRE device can be used when upgrading to thermostats that need a "COMMON" wire from one that didn't have one... and there is no way to run the additional wire needed.  This device, ranging from $15 to $40 can come in very handy especially in the case of zone control where one or more thermostat does not have enough wires to accomodate a modern thermostat such as a WiFi thermostat.

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Be sure to follow the wiring diagram for the specific model of "ADD-A-WIRE" as well as the system type.  Show here is the LUX Products LPB-WH Power Bridge wired to a GAS/ELECTRIC thermostat and SmartZone-4X controller, however, the basic principal is the same for any application.

All of the different ADD-A-WIRE models come with instructions, read them carefully and follow exactly and you won't have any problems.

For more information about the method of ADD-A-WIRE when there is no way to run an extra wire from your zone panel to your equipment, check out this post:
https://zoningsupply.com/blog/upgrading-thermostats-solving-a-common-problem

From an engineering perspective this is an elegant and simple solution.  Without giving away trade secrets, the ones i have tested use the a half wave bridge using diodes at the thermostat and some simple relay logic plus the another half wave at the equipment (no micro necessary) to use only 1 wire for both Y and G signals.... brilliant.

For more information, or with any questions, please contact us.

De-humidification and SmartZone - Zone 1 Thermostat Control

Although SmartZone does not have any built-in capabilities for controlling DE-humidification (DH) or Humidification, some applications are possible by using a thermostat on ZONE 1 that does have the capability to control DH.

“DE-humidification, in most residential systems, is simply running the equipment in COOLING with LOW speed fan instead of HI speed fan.”

Before we get to zoning, the equipment being used must have the capability to control humidity.  This usually means it has a terminal (DH/BK/DS) that is energized or DE-energized by a thermostat to control fan speed of the equipment.  Controlling fan speed allows the equipment to DE-humidify the air when the fan is running in low speed.

Back to zoning, using zone 1 thermostat to control DH is not as simple as wiring directly from the thermostat to the equipment.  PLEASE DO NOT DO THIS.  The equipment and the zone thermostats are running on different transformers and this will case problems and potentially damage to some components.  You could isolate the output from the thermostat with a relay to get around this issue of different transformers but you would still have an issue with this method of wiring "around" the zone controller.  The issue can arise when zone 1 calls for DH but the equipment is already running in heat, this mixed signal might just be ignored by the equipment but we cannot take that for granted... all equipment works differently.

The best way to control DH using SmartZone on single stage equipment is by using the method below.  It may seem a little UN-orthidoxed but it is a valid APP note from the engineer at Ecojay (It's intended to work this way).

1. Select a DH enabled thermostat of your choice
2. Connect Y2/ECO on SmartZone Zone 1 to Zone 1 Thermostat DH/DS/BK
3. Connect Y2 on SmartZone Equipment toEquipment DH/DS/BK
4. Set Zone 1 "STAT TYPE" to G2
5. Set DIP switch #4 to "LOCKOUT"

Zone 1 thermostat will now enable and disable DE-humidification any time the equipment is running in the cooling mode.
NOTE: When starting cooling from OFF state, 90 second delay will occur before HIGH speed fan will energize.

Using this method we are assuming that the equipment is expecting DS/BK/DH input terminal to be ENERGIZED for high speed fan and DE-ENERGIZED for low speed fan.  This method should not be used for more than 3 zones or with multi-stage compressor equipment.

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sale

SmartZone-2X

Sale Price:$159.99 Original Price:$199.00

Quantity:

Add To Cart

This application will work with Ecojay's SmartZone-2X and SmartZone-4X.  Learn more

Click for SmartZone-2X/4X Install Guide

WiFi Thermostat Roundup 2017

Just a few short years ago, WiFi thermostats were only made by a very few companies starting with Ecobee and RadioThermostat, followed by Nest.  A couple of years pass and big names in the HVAC industry (Honeywell, Emerson, Venstar, etc) join the WiFi thermostat party.  In 2017 we have more to chose from than can easily be kept up with.  Note: All prices as of this article publish date.

All of the WiFi thermostats listed below will work with any SmartZone

I am sure there will be even more on the market in 2018, we will keep watching the WiFi thermostat bubble grow!  More than 15 are listed here (and I know they are not all listed).  If you know of any more, comment or tweet to us @zoning_supply

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Bosch - $ 170, 4-Heat, 2-Cool, GE/HP, Hum, deHum, Color: White
https://www.amazon.com/dp/B073XHD8BB

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Ecobee Si - $ 145, 2-Heat, 2-Cool, Color: White
https://www.amazon.com/ecobee-Thermostat-Heat-2-NON-Touch-Screen/dp/B008F40R4C/

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TOP PICK

*Ecobee 3 - $ 169, 3-Heat, 2-Cool, Best for zoning in our opinion.
https://www.amazon.com/ecobee3-Smart-Thermostat-Works-Amazon/dp/B06W56TBLN/

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PREMIUM CHOICE

Ecobee 4 - $ 247, 3-Heat, 2-Cool, Alexa-Enabled
https://www.amazon.com/ecobee4-Alexa-Enabled-Thermostat-Sensor-Amazon/dp/B06W2LQY6L/

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Emerson Sensi Color Touch - $ 169, 2 Heat, 2 Cool, GE/HP
https://www.amazon.com/dp/B01N3CEUDH?psc=1

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Emerson Sensi - $ 99, 1 Heat, 1 Cool, GE/HP
https://www.amazon.com/dp/B00HHE6CW2?psc=1

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Nest - $ 249, 3-Heat, 2-Cool
https://www.amazon.com/dp/B0131RG6VK/

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Honeywell Color Touch - $ 190
https://www.amazon.com/Honeywell-TH9320WF5003-Touchscreen-Thermostat-Amazon/dp/B00G4CIG7M/

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Honeywell Lyric T5 - $ 110
https://www.amazon.com/Honeywell-RCHT8610WF2006-Programmable-Touchscreen-Thermostat/dp/B01LTHM8LG/

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Honeywell Lyric Round - $ 170, Geofencing
https://www.amazon.com/Honeywell-Thermostat-Contractor-Version-Amazon/dp/B00KX3M1LA/

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Honeywell Basic 7-day - $ 90, 1-Heat, 1-Cool, GE, Color: White (Yes this is WiFi--even though it doesn't look like anything other than an inexpensive thermostat)
https://www.amazon.com/dp/B00Y6M2OUC/

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Honeywell B&W Touch - $ 118
https://www.amazon.com/Honeywell-Wi-Fi-Programmable-Touchscreen-Thermostat/dp/B00EP6C8UA/

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iDevices Thermostat - $ 112
https://www.amazon.com/iDevices-Thermostat-Wi-Fi-Works-Amazon/dp/B019GQM6LY/

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VALUE CHOICE #1

Lux PRO GEO - $ 115, Geofencing, Mount Vertical or Horizontal, Color: Black or White
https://www.amazon.com/Lux-Products-GEO-WH-Thermostat-Amazon/dp/B010PTKWW6/

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RadioThermostat - $ 99, 2-Heat, 2-Cool, GE/HP, Modules for Zigbee & Z-Wave
https://www.amazon.com/Radio-Thermostat-Programmable-Enabled-Controls/dp/B00KQS35XA/

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VALUE CHOICE #2

*Vine - $ 99, Settings Knob, Color Screen & Night-Light
https://www.amazon.com/Vine-Programmable-Thermostat-Touchscreen-Nightlight/dp/B01JU1DZN8/

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Vine Touch - $ 129 Color Touch Screen,
https://www.amazon.com/Vine-Smart-Wi-Fi-Thermostat-TJ-919/dp/B01N7UNSAP/

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Any information in this article should be verified with the manufacturer of each product listed.  Specifications, prices & availability are all subject to change and will not be kept current on this post.  Please email us if you have any questions.

ALSO NOTE:  We (I) have not been paid or compensated in any way for this article by any of the manufacturers of these products.  I have not even received any free product... anything reviewed has been purchased through retail outlets and tested with SmartZone zone control products for the use of ZoningSupply.com customers.  This information is not intended to be exhaustive or claim expert knowledge about all of these thermostats.  Thank you.

Ashrae 62-2 Ventilation (Fresh Air) sizing & calculation

Many homes these days have such tight seals around doors, windows, and even closed-cell foam insulation... they are almost air-tight.  You can think of an old house like an antique metal or wooden ice box where modern homes are more like Yeti coolers.  While this is great for keeping temperatures steady inside the home, it also can trap moisture and toxic gases inside.  Fresh air ventilation is necessary to keep a healthy and efficient home.

But how much fresh air is needed?  If you bring in too much, you will make your HVAC equipment work too hard and loose efficiency.  If not enough fresh air is brought into the home, the air can become humid and allow mold growth or VOCs and other toxins can build up.  Luckily, the national organization ASHRAE has a specific recommendation for the amount of air based on occupancy and square footage of the home.  See table below.

Taken from SmartZone-4X Install Guide

However, this table should not be taken as gospel.  Just like other HVAC calculations and estimations, many factors are not really being taken into account with this rough estimate based on # of bedrooms (occupancy) and square footage.  Some adjustments may be needed based on factors such as climate, ceiling height, other air-leakage, etc.  To comply with 62-2 is the baseline & adjustments can be made in the field by setting run-time.

Learn more about how SmartZone-4X can control fresh air more efficiently than a separate fresh-air controller in the Install Guide

SmartZone is great opportunity for DISTRIBUTORS.

There are many reasons that distributors should take a look at stocking SmartZone, but basically because they can make more money & have a higher customer satisfaction with a very low up-front investment.

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1. Only 2 models needed to cover all applications.
   A lot of manufacturers require stocking 5,6... even dozens of different products to get the best price.  With SmartZone, you only need the SmartZone-2 and the SmartZone-4X.  That's right, only 2 models will cover everything from 2 zones to 20 zones, single & multi-stage, gas/electric & heat pump (including dual fuel).  As a bonus, the SmartZone-4X has built-in Fresh-Air control.
    
2. Best wholesale pricing.
   Options for small and large volume distributors with 30 day NET terms pending credit approval.  Start with a small order or only 10 zone controllers.  Contact ECOJAY (www.smartzoning.com) for details.
    
3. Documentation & training.
   Ecojay is committed to supporting distributors with documentation, signs, marketing materials, phone & online support.  Ecojay will even do an in-person training for contractors at new distributor locations (minimum order required for free training - normal price for training $500)
    
4. Increase zone control profits & sales.
   SmartZone has allowed many of our distributors to increase sales of zoning because it is so much easier for contractors to use & install... they buy more.  Distributors of SmartZone also have increased margins on the higher-end controllers because SmartZone-4X can do everything the Honeywell HZ432 can do at a much lower price.
    
5. Contractors will love you for it.
   Even contractors that "don't do zoning" occasionally come across a system that needs it or a customer that wants it.  SmartZone is the best the the occasional zoning contractor or the contractor that does it every day.  Most contractors that try it, don't want to use anything else.

Right now, only about 25-35% of the US has physical distribution of ECOJAY products, specifically SmartZone.  This is a HUGE missed opportunity.  Online distribution reaches nationwide, but even this is in it's infancy.  SmartZone deserves to be on the shelf of your local distributor and contractors deserve to have access to it.  Right now it is available on Amazon.com, Ebay, ZoningSupply.com for contractors in the US & Canada to have in a couple of days shipping time.

It would be great if some of the large online supply houses like ... Supplyhouse.com or AlpineAir.com would stock SmartZone so it could be purchased and shipped along with systems.  Or some of the national-chain distributors like Johnstone would also carry SmartZone for the sake of availability and exposure to SmartZone style zoning.

SmartZone is not a new gimmic in zoning, it is simply the BEST traditional forced-air zone control board that is available.  SmartZone has been designed with the HVAC contractor in mind and it shows with the feedback that is received over and over again from contractors.  SmartZone has been shipping since 2004 and has had rave reviews from the beginning. 

Contractors that never liked zoning before even love SmartZone.  Many of the problems that people had 10 or 15 years ago with zoning such as freezing coils or short cycling have been solved by more sophisticated zone controls but SmartZone made it simple.  Using Ecojay SmartZone makes zoning simple.

Get SmartZone at ZoningSupply.com

See why SmartZone is the best zone controller on the market.

ZoningSupply.com for all your zone control and damper products at the best prices with FREE shipping.

Air balancing information & IOT evaluation from ContractingBusiness

Good articles that can affect HVAC zone control

“If your technicians aren’t checking system airflow on every service call, you’re doing your company and your customers a disservice. Air balancing is the missing link in getting residential HVAC systems to perform at or near their peak levels.”

— ContractingBusiness.com

http://contractingbusiness.com/iaq-amp-ventilation/residential-air-balancing-missing-link

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“It is easy to be confused when it comes to the Internet of Things (IoT), with so many products and objects being connected and made more intelligent. It sounds overly complex, but one application that is easy to understand is HVAC IoT.

HVAC IoT is made up of a system of smart thermostats placed throughout building zones. The devices, and therefore the zones, are connected over wireless and software and work together as one brain. The brain has a nervous system with sensor endings in every room, hallway or lobby to monitor any environmental changes that could prompt the HVAC system to react”

— ContractingBusiness.com

http://contractingbusiness.com/controls/hvac-and-iot-simply

HVAC Contractors: Out-Perform the Competition with ZoningSupply.com

Contractors nowadays are finding that homeowners and business-owners are looking for all the bells and whistles they can reasonably afford and install. Among features like energy-efficient fixtures and home-automation, HVAC zoning is usually near the top of this list. Of course, zoning offers multiple benefits to homes and buildings as it can save energy and provide a custom level of comfort.

As HVAC zoning rises in popularity, homeowners and business-owners are beginning to ask for it by name.

How can contractors make the most of this movement?
It starts with choices. Many contractors have unfortunately limited themselves to zone control systems that sit at the top of the market (as well as the top of the price-range.) This would be great if these “name-brand” zoning systems offered quality, reliability and features that justified the price. This is simply not the case. Contractors who have worked with zoning for a while can attest to this. The good news is that there are now many choices when it comes to zone controls, dampers, and equipment. Contractors and suppliers can now sift through the choices and figure out which systems are the simplest to install, the most reliable, and provide the best customer support.

This is where ZoningSupply.com comes in. ZoningSupply guarantees their products to be the most reliable, the easiest to install, and the most affordable in the marketplace. Hundreds of contractor and homeowner testimonials over the past 10+ years sing praises of the top-notch products they offer.
Here’s why . . .

Contractor-Friendly
The engineers behind ZoningSupply products will tell you that their systems were designed with the contractor in mind. In other words, full-color install guides, screwless wiring, and color-coded LEDs are only the start. If a contractor picks up the phone and talks to Jeff or one of our other tech-support specialists, they’ll be sure to have all of their questions answered quickly but thoroughly.  

Easy-to-follow instructions and simple design make for a lightning-fast install.  

Ship Direct for Free
Furthermore, ZoningSupply.com can ship anywhere in the U.S. for free. Individual components or entire systems can be purchased on the website and delivered straight to your office or job site,  

Affordable
ZoningSupply’s featured SmartZone 2x, 4x, and 2L systems are among the most affordable in the marketplace. This puts money in your pocket and provides savings that can be passed along to homeowners.

Universally Compatible
If a contractor uses ZoningSupply, they can confidently offer retrofit options for virtually any existing HVAC system on the market. This means not having to learn and re-learn various installation procedures. This also means that nearly every home or building in your area can be retrofitted for zoning . . . Think of the opportunities!

With zone control systems, as with any product, there are the good, the bad, and the ugly. In the end, they all must answer to the contractors and ultimately the homeowners. When bidding on projects or marketing their services, contractors should equip themselves with the confidence and reliability that ZoningSupply.com products provide.  

More unbiased Zone control discusson on homeenergy

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QUESSTION by Adam Zielinski

Homeowners with forced air duct systems always want to close the registers in rooms they aren't using, and close the doors to those rooms, in the belief that doing so will save energy and money.
I always thought doing this was over-rated and unlikely to save a significant amount of energy or money.  I could see doing it for one or two rooms perhaps, but sometimes homeowners close off half of their house or more.
This creates unbalanced air flow in the duct system and likely results in over heating the furnace heat exchanger, and or short cycling the furnace.  So the furnace spends a lot of time in start up mode and less time at peak efficiency.
I have not seen any real studies done on this however.  I'd like to see some data or research on this.

Reply by dale conner
Adam, most furnaces will move the proper amount of air through the blower and heat exchanger if the furnace cabinet pressure doesnt exceed .5 IWC and the furnace capacity was chosen based on a manual J calculation. This information can be found in the furnace installation manual or IOM (installation,operation,maintenance) that comes with a new furnace. However, this does not mean we are getting adequate air delivery to all of the rooms in the house due to excessive air leakage in the ducts and/or incorrect duct lengths or diameters routed to each room.

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QUESTION by Judi Lyall

How about using a motorized damper ?

Reply by dale conner
A single motorized damper can be used to control a zoned area but you also have to install a barometric by-pass damper to prevent over pressurization www.zoningsupply.com

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See full discussion: http://homeenergypros.lbl.gov/group/hvac/forum/topic/show?id=6069565%3ATopic%3A7207

Honest discussion on homeenergypros about zoning advantages.

Are Zoned Heating/Cooling Systems a Good or Bad Idea?

Excerpt from homeenergypros discussion about HVAC Zone controls.

QUESTION by Jon LaMonte

For starters, I live in Atlanta, Ga and I am not an HVAC pro so this is a serious question that I would like answered for one of my clients.  I understand the premise of a zoned system and on the surface, it sounds like a good idea. Then I considered the fact that I have always told my customers that it is a bad idea to close off vents in rooms they are not in because of duct leakage.  Also, the second law of thermodynamics simply states the hot goes to cold, so now the unheated areas are doing their best to rob warm air from the heated areas.  Finally, if your zoning a single system, aren't you creating on oversizing issue because the unit (that was probably oversized in the first place) is now servicing a smaller area than what it was designed for?

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Reply1 by Chris Heenan

Zoning has benefits beyond temp control. Most often the home does not require the full 2 stage heat or cooling as the system only needs to satisfy a portion of the home. So, then if 1/2 the heated air goes through a properly sized and balance bypass, the return air (from home) will mix with warm supply (from bypass) before going thru the system again. You may not need to go beyond 1stage heat (or cool) except in extremes. This is most beneficial in raising supply temps from heat pumps when in winter mode. Most supply vents feel 'cool' to homeowner. Not so when zoned and not call on all zones.

Flip it to cool, and the bypass send dehumidified cooler air across the coil. Decreasing high side pressures and amp draw of compressor. Then the air gets more heat extracted and further dehumidified. Pulling out additional condensate and running less. Remember systems have to be careful not to oversize as dehumidification is crucial to comfort. Dry and cool temps out supply vent. Not too shabby.

Reply2 by dale conner

Zone sytems are rarely installed properly but can be efficient if properly designed. The goal is to be able to set back the temperature a few degrees in a zone that isnt being utilized while keeping another zone comfortable that is being utilized.  A single unit with a zone system will have a by-pass duct sytem to dump the air thats been cut off from one zone back into the duct system to be used in the zone that is being used.

*Reply3 by James Jackson on

Have you ever been driving down the interstate hwy and come up on an exit ramp that has traffic backed up? As the traffic backs up and eventually fills the exit with cars you end up with a slight back up on the entire highway. this is the closest scenario i have been able to come up to help people understand why closing doors and vents is a bad idea. if you have a run off of a main trunk and you close the outlet or register you will cause the air to back up into the trunk causing turbulence in the trunk line resulting in a decrease in air flow in other areas on the system. this can also cause multiple other problems like pulsing and excessive noise from the increase in pressure.

another thing to remember when you shut doors in a home with no return air you cause a difference in pressure in the home. The room you have closed is now significantly positively pressurized and the house is now under a negative pressure. This why some homes have the doors undercut by 3-4 inches trying to allow the air to get back to the return.

Ok as far as the zone system goes... There is so much more thought involved in properly setting up a quality zone system that i see very few done correctly. If you want to do one correctly you first need to make sure you are using a multi-stage HVAC unit so the unit can run on low speed if it is only conditioning one zone. A bypass or crossover duct with a barometric damper is needed if you are conditioning a small zone and the air handler is still supplying too much air, but if you are going the zone route don’t use contractor grade units and piece it together with a simple zone controller. Get a high efficiency v speed unit that is designed for this application.

But what happens when you change the temps in a zone in the house 4-5 degrees?? Energy moves from hot to cold so you end up indirectly heating or cooling the entire space regardless. This brings us to another scenario. The return air in the zone that is off. My experience with working on correcting issues with homes using zone systems has been the returns are never dampered so if the zone is completely shut off you have just installed a permanent blower door. if the zone is off one you are returning hotter or colder air to the system and two you are causing that zone to have a negative pressure.

Just some things to think about !!

Learn more at www.zoningsupply.com

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BETTER with Zoning done right!

Single thermostat can have issues

My editorial conclusion:
Zoning CAN be effective if and ONLY if it's designed and installed properly.  This means ducts, dampers, equipment size (tons).  It also means the right zone panel setup with energy saving features like SmartZone.  Finally, to make zoning work best and comfort control and energy savings, the home owner must properly control the thermostats.  Zoning isn't a "set-it-and-forget-it" system, it must be managed to be effective.  More articles about zoning

See full discussion: http://homeenergypros.lbl.gov/group/hvac/forum/topic/show?id=6069565%3ATopic%3A7207

Retro thermostat... 1982 Electronics Guide review of Magic-Stat

Published in Playboy's Electronic Entertainment guide in Fall 1982. 

This is off of our normal subject but I came across this old magazine that includes other articles like "There's more to life than Pac-Man: How to beat Donkey Kong" and "What computers can do for you" which says that "VisiCalc is the most popular program of all time with 250,000 copies sold".  And it included a scathing review of this Magic-Stat product.  Sold for $79 mail order.  At first glance, I thought it was just another ugly thermostats in a long history that still goes on today.  Then i read the article which explains a "LEARN" mode that makes it easier to set much like the nest would do decades later.  Also, it claims to have what is now reffered to as "adaptive recovery".  This is where the thermostat starts the equipment before the set time so it can get the home to temperature at a specified time instead of just starting to get to temperature at the time of setpoint.  I haven't done any fact-checking, but it says they are the first thermostat to do this... too bad it took 20 years for this to become a more standard feature.

Here are a few more pics I took of the magazine...i claim no rights or ownership of any of this material.