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sorry t527ed. i have to disagree. if you are going to work for builders there are going to be compromises made on the perfect system we would all love to put in every time and never have to go back to. designing and estimating the perfect system would leave my company without a lot of builder work. i would love to meet a few builders who are more interested in a good system rather that the bottom line. i wish a few more would be willing to give us a little duct chase or maybe double a wall. best builder i have seen in the new jersey area for hvac designs (they engineer their own) is pulte homes. all you have to do is beat their low numbers and you get to put them in.
Regular Guest
I have got the same problem. I have a 20 year old 2000 sq ft house with 4 bedrooms upstairs and fairly new Trane heat pump (xr11). Tried attic exhaust fan but that was not much help. I am located in mideastern region which can be hot and humid in summer. Have original blown fiberglass insulation in attic and would be willing to try cellulose on top. What is involved in zoning and is it usually expensive to add on ? Does it require two separate heat pump systems or just two thermostats ?
Professional Member*
Chris, that is the reason my company never has and never will do work for tract housing. only new constuction we have ever done is custom houses for people we have worked for before or been referred to. we were hooked up with a small builder doing a few houses a year but he became the same as the others and we cut him loose. did not spend 35 years building reputation to compromise it for new construction.
Regular Guest
All "zoning" is is the abiliity to control the temperature of several areas of the house, thus "zones".Originally posted by seabreeze
I have got the same problem. I have a 20 year old 2000 sq ft house with 4 bedrooms upstairs and fairly new Trane heat pump (xr11). Tried attic exhaust fan but that was not much help. I am located in mideastern region which can be hot and humid in summer. Have original blown fiberglass insulation in attic and would be willing to try cellulose on top. What is involved in zoning and is it usually expensive to add on ? Does it require two separate heat pump systems or just two thermostats ?
This can be done a number of ways, but the most common ones are:
1 installing motorized dampers in the ductwork to divert the air to where it is most needed.
2 adding a second system to take care of the problem area independent frrom the main system.
Zoning using dampers requires that you have ductwork that can handle the changes in airflow. If your ductwork has problems, then your zoning will have problems.
Many homes have inadequate return and supply ductwork. Expecting to fix their problems with a zoning system is unrealistic.
Zoning using a second system is just that, a complete new system is sized and installed to heat/cool the problem areas. This would typically be a unit for the second floor, or one for a new addition. It requires having the space to install the equipment, and new ductwork.
As far as expense, only a contractor who does a lot of zoning on existing houses can give you the correct answer. It can often go either way.
It depends on how the existing system is set up, how easy it is to get to the ductwork, and if the system has the capability to handle the changes.
Likewise with a second system, how hard is it going to be to install.
Insulating your house and making it weather tight is always the first place to start.
Regular Guest
Dave, thanks for the info. I am going take your advice and start with adding insulation. Then for the heck of it, I am going to contact my installer about the motorized dampers.
Regular Guest
thats probably the best way to do it. i would love to cut loose a few of ours.
Professional Member*
There are some great "Retro-Fit" zoning systems on the market today.
I agree with Dave that you need to contact an experienced retro-fit zoning contractor (or two) in your area that can evaluate your system.
What we have found over the past decade is that zoning an existing (ineffective) duct system can overcome many duct inadequaces and that the ducts feeding those zone will handle up to 200% more air than what they were designed for.
If you need names of any local contractors using the Arzel zone system let me know.
Good Luck!
Regular Guest
jramunni - thanks, do you know of any Arzel reps in the DC, Md Va area ?
Professional Member*
Being that no one in this forum stepped forward from your area, why don't you call me and I will pass on some contractors that we work with in your area. 1-800-611-8312
Ask for Joe!
Professional Member
The problem with trying to condition 2 floors on 1 system always revolves around moving air where physics 101 says "I don't wanna go.
Here is how I explain it to potential customers. Mr. X, your home is the same size up and down, and common sense tells you that you need the same ammount of airflow for each floor. The problem is, this is 100% wrong - in the winter you need 70% of your air downstairs, because heat rises, but in the summer you need 65% of you airflow upstairs, because of the attic and cold air falling.
If you are trying to retrofit, you will have to find the space to increase the return ((I always figure 60 of total return air needed and there is NEVER enough existing return air) and also have a large enough supply trunk. If the air handler has to be on the first floor, the supply trunk needs to go straight up to the attic with no turns (every turn is like 10' of equivalent length) and you are already going up 20'+ to reach the attic.
Zoning works IF AND ONLY IF you can get the proper airflow
to the area and if the system is designed for good humidity control (zoning people will tell you to reduce a 3 ton load to 2 1/2 tons because normally only 1 zone at a time calls. Zoning is expensive, and I really prefer 2 systems over 1
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classicrock4you
Zoning works IF AND ONLY IF you can get the proper airflow
to the area and if the system is designed for good humidity control (zoning people will tell you to reduce a 3 ton load to 2 1/2 tons because normally only 1 zone at a time calls. Zoning is expensive, and I really prefer 2 systems over 1
Becareful condeming "Zoning" when you obviously have not succefully applied it with the right product in the proper way and had the succes many contractors are achieving.
Zoning will always increase CFM delivery to a single calling zone, many times by up to 100% when we close off zones that are satisfied and allow supply static to elevate. As supply static elevates, the total airflow and velocity across the coil decreases allow the coil to remove a higher percentage of Latent heat. The end result is that we move more, colder, dryer air to the zone that is at peak load. The key is allow the supply static to increase when non peak zones are satisfied and closed off.
Zoning actualy does increase dehumidification if applied properly.
The Eight edition of Manual J does recommend downsizing equipment when you are zoning and the structure has AED (Adequate Exposure Diversity) in section 1-13, page 1-4 through 1-8.
Regarding cost, you need to refigure your job cost comparisons. With the right zoning product you should be selling retrofit zoning at a lower price to your customers and making a higher profit than you would if you sold them a second system. If your not you are by all means doing something wrong.
If you are ever in the Cleveland area, stop in and I will demonstrate the affects of zoning in our Zoning Dynamiocs Lab.
Regular Guest
Quick idea, would like feedback. What about taking the 6" supply ducts to the second floor and making them 8". Of course this is just in the basement and not in the walls. Would that help cool the upstairs?
jramunni...any good contacts in the Cincinnati Area? I am looking to install A/C and Gas Furnace.
Professional Member*
sslusher...Three reputable contractor in the Cincinnati area that we work with,
- Jacob Bros (Cincin)
- Jonle Htg & A/C (Cincin)
- Tanner Htg & A/C (Dayton)
Professional Member
The problem is, much of the newer, high efficiency stuff has blower capacity restraints which do not allow statics to be very high. Many of the zoning mfg's have failed to accept this. Part of the efficiency is to remove the excess unnescessary blower wattage. If it has a ECM, it may be able to overcome the static but throws a wrench in the bypass operation if it is used.Originally posted by jramunni
Becareful condeming "Zoning" when you obviously have not succefully applied it with the right product in the proper way and had the succes many contractors are achieving.
Zoning will always increase CFM delivery to a single calling zone, many times by up to 100% when we close off zones that are satisfied and allow supply static to elevate.
You do make a good comment that it must be applied properly, unfortunately most are not.
Professional Member*
[QUOTE]Originally posted by docholiday
The problem is, much of the newer, high efficiency stuff has blower capacity restraints which do not allow statics to be very high. Many of the zoning mfg's have failed to accept this. Part of the efficiency is to remove the excess unnescessary blower wattage. If it has a ECM, it may be able to overcome the static but throws a wrench in the bypass operation if it is used.
I am not refering to external static pressure but supply static pressure. What actualy happens as you close off dampers to satisfied zones is the supply static increases, the return static decreases, the external static increases (only as a sum of the supply and return) and the blower amps(watts)decrease. Blower wattage is affected by cfm deliver and not static pressure. Being that cfm output goes down, so does wattage.
The beauty of ECM variable speed systems is that you can many times operate the furnace/air handler at low stage cfm/output when only one zone is calling and deliver the decreased capacity through less of the duct and maintain the velocity required to get it were you need it.
Professional Member
Juri, don't get me wrong here. Zoning is a great thing and I have been very successful with it in the right application.
Refer back to the origional post - this is a new 2 story home with a new HVAC system (Blower in basement)that does NOT work. Somebody has already screwed up and we are being asked to help. I bet $$$ that the main supply trunk and the return trunk to the attic are inadequate now. Even worse, it could be one of those abominations where 1 common trunk feeds both upstairs (in floor) and downstairs (in ceiling.)My experience has shown that in these situations it is hard to enlarge the trunks as needed withou really doing major modifications.
My point is that zoning is a great system when it is designed for zoned or when all the requirements are there. In this situation, however, we dont know enough to recommend that.
Professional Member*
_________________________________________________Originally posted by classicrock4you
Juri, don't get me wrong here. Zoning is a great thing and I have been very successful with it in the right application.
Refer back to the origional post - this is a new 2 story home with a new HVAC system (Blower in basement)that does NOT work. Somebody has already screwed up and we are being asked to help. I bet $$$ that the main supply trunk and the return trunk to the attic are inadequate now. Even worse, it could be one of those abominations where 1 common trunk feeds both upstairs (in floor) and downstairs (in ceiling.)My experience has shown that in these situations it is hard to enlarge the trunks as needed withou really doing major modifications.
My point is that zoning is a great system when it is designed for zoned or when all the requirements are there. In this situation, however, we dont know enough to recommend that.
...I get your point but I do not agree with your lack of confidence in the positve affects of zoning. Our market is built on the success of this exact application. Two story home with the furnace in the basemsnt The sum of several positive changes provides comfort to the second floor.
1 - Increased cfm delivery to 2nd fl registers
2 - Increased velocity (throw)at 2nd fl registers
3 - Colder/Drier air to 2nd fl (due to lower total cfm)
4 - Longer A/C cycle (due to 2nd floor stat having control)
We have been in the "Retrofit" zoning business for 15yrs and have received to much overwhelming, positive feedback on the dramatic effects of adding zoning to an existing (not always adequate) system to not shout it from the mountain top.
Regular Guest
Hello Juri:Originally posted by jramunni
...I get your point but I do not agree with your lack of confidence in the positve affects of zoning. Our market is built on the success of this exact application. Two story home with the furnace in the basemsnt The sum of several positive changes provides comfort to the second floor.
1 - Increased cfm delivery to 2nd fl registers
2 - Increased velocity (throw)at 2nd fl registers
3 - Colder/Drier air to 2nd fl (due to lower total cfm)
4 - Longer A/C cycle (due to 2nd floor stat having control)
[/B]
I have a two-story split-foyer house. Two ducts come off the plenum in the utility room at one end of the house. The small duct supplies three branches to adjacent rooms upstairs and downstairs. The large duct runs the length of the house between the floors. All room branches run off the top of this duct between joists to ceiling registers for the downstairs and to outside wall registers for the upstairs.
How would you deal with this? Thank you.
Al
Professional Member*
AlOriginally posted by alinnova
I have a two-story split-foyer house. Two ducts come off the plenum in the utility room at one end of the house. The small duct supplies three branches to adjacent rooms upstairs and downstairs. The large duct runs the length of the house between the floors. All room branches run off the top of this duct between joists to ceiling registers for the downstairs and to outside wall registers for the upstairs.
How would you deal with this? Thank you.
Al
[/B]
Is the main duct and bransh duct exposed (accesible)?
Our typical damper install is an insertable damper in each (accessible) branch run (5",6",7" round).
If the branch runs are not exposed but the main trunk is, or can be, we have dampers that are inserted up through an opening cut in the main duct below each take-off and lock them selves in place just past the take off in the round duct. Our third damper option is in the register boot with the air tube run throught the branch duct and accessed in the main trunk. The concern with the 3rd option is air noise (whistling)when the damper is closed being that you are now dampering in the room with a louvered damper.
For many homeowners "Comfort at Last" is more important than a little noise from time to time.
jr
Regular Guest
After the main duct leaves the utility room, it and all its branches are enclosed by floor above and ceiling below. To access each branch would require a hole through the ceiling. Each branch is rectangular, 3 1/2 inch by 8, 10, or 12 inches.Originally posted by jramunni
Is the main duct and bransh duct exposed (accesible)?
Our typical damper install is an insertable damper in each (accessible) branch run (5",6",7" round).
If the branch runs are not exposed but the main trunk is, or can be, we have dampers that are inserted up through an opening cut in the main duct below each take-off and lock them selves in place just past the take off in the round duct. Our third damper option is in the register boot with the air tube run throught the branch duct and accessed in the main trunk. The concern with the 3rd option is air noise (whistling)when the damper is closed being that you are now dampering in the room with a louvered damper.
For many homeowners "Comfort at Last" is more important than a little noise from time to time.
jr
Al
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