Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > HVAC

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Search this Thread Display Modes
Old 02-12-2012, 12:21 AM   #16
Member
 
Join Date: Dec 2011
Posts: 108
Share |
Default

Uneven temps - Solutions? Looking for advice/opinions


Quote:
Originally Posted by plummen View Post
If the ductwork is all in the attic why didnt they set the air handler up there also?
Updrafts on floor level are just as common as attic handlers/furnaces here.
The attic placed systems seem to be in every 2 story i've ever seen in north texas. The one stories seem to have been a toss up.

Someone told me that one theory is it helps reduce the introduction of more heat into the system. (Air handler in attic would be attic temp, one in house would be at room temp or very close to it.. each cycle would push more warm air into house). This seems to make sense to the common person(Me - I'm no HVAC pro). The heat capacity for an air handler, I'd imagine, can be pretty great. That's 150+ lbs of mostly metal that needs to be cooled(or heated)

fuzzball03 is offline   Reply With Quote
Old 02-12-2012, 04:54 AM   #17
An old Tradesmen
 
Join Date: Oct 2008
Location: PA
Posts: 24,527
Default

Uneven temps - Solutions? Looking for advice/opinions


First. That CFM rating is probably at an ESP of .3", and since they used all flex, your static is probably much closer to .8", so your not anywhere close to moving 1354 CFM.

While 3 tons may or may not be over sized for you area. You don't have the duct work/system for 3 tons.

WAG. The 9" feeding the kitchen and Family room, should probably be a 12", and the family room should probably have 2-7" supplies, and the kitchen a 7" supply. The 8" feeing teh Dining room and bedroom 4, should probably be a 10" and the Dining room should have a 7" supply, and bedroom 4 should probably have a 7 and a 6" supply, or 2-7" supplies.

And yes, find a way to add more return for the air handler.
beenthere is offline   Reply With Quote
Old 02-12-2012, 05:55 AM   #18
Member
 
Join Date: Dec 2011
Posts: 108
Default

Uneven temps - Solutions? Looking for advice/opinions


Quote:
Originally Posted by beenthere View Post
First. That CFM rating is probably at an ESP of .3", and since they used all flex, your static is probably much closer to .8", so your not anywhere close to moving 1354 CFM.

While 3 tons may or may not be over sized for you area. You don't have the duct work/system for 3 tons.

WAG. The 9" feeding the kitchen and Family room, should probably be a 12", and the family room should probably have 2-7" supplies, and the kitchen a 7" supply. The 8" feeing teh Dining room and bedroom 4, should probably be a 10" and the Dining room should have a 7" supply, and bedroom 4 should probably have a 7 and a 6" supply, or 2-7" supplies.

And yes, find a way to add more return for the air handler.
First off! Thanks, seems to be one of the most specific and helpful replies so far.

Thanks for pointing that out - I have nothing to measure pressure with, so i was just pulling from the manual. I assumed .3" was the norm - Looks like I was wrong! I've attached the Handler and Heat Pump manual for additional reference.
The manual states(highest listed) that @.5 in. Med Speed is 1090CFM


So far, this is looking like the best fit.(Your suggestions)
I download HVAC Calc... Looking at all the numbers, every duct you mentioned are ducts that are very far off from what I have.

Additionally - it seems to be suggesting that every supply at these are too large: All baths, food pantry, walk in closet, utility room. I think I wont worry about downsizing any of those - If need be, a damper at the air distribution box should be a good solution.
Should I be adding a heat load to the laundry room?(Beyond the door)

Also - what's your thought on a return in the food pantry? It's my only other option without doing some very pricey and extensive.


If i add that return - I'll need to increase the filter surface area.
So:
-remove current filter completely(filter is mounted directly underneath handler)
-make both return registers filtered type registers

I should be able to do a 16x25 at both locations, possibly one 16x25 and one 20x25. I may go with two of the same, and even go with the 4" varieties. 16x25x4 and 20x25x4 seem to be readily available in my area... even more so online.
Does all that sound right?

http://www.filedropper.com/14hpxseri...nstallinstruct
http://www.filedropper.com/l0805350


...Also interesting, from the manual:
"IMPORTANT - The horizontal drain pan is not required in upflow air discharge installations; its removal provides the best efficiency and air flow."
"the minimum open area for the louvers will be... 360 square inches for -030 and -036 models;"
So do I tell them to come remove the drain pan? Ha, or are they just going to mess something else up...

Since this is not a horizontally mounted unit... Should i take off the "blow off prevention bracket" ? Doesn't seem necessary in an updraft config. Even stranger is the manual states there isnt one isntalled on the -037; yet there is one on my handler.
I also noticed that my air distribution box in the attic has an address written on it... for a house down the street.
Questions... questions...

Last edited by fuzzball03; 02-12-2012 at 06:17 AM.
fuzzball03 is offline   Reply With Quote
Old 02-12-2012, 06:12 AM   #19
An old Tradesmen
 
Join Date: Oct 2008
Location: PA
Posts: 24,527
Default

Uneven temps - Solutions? Looking for advice/opinions


Could leave you with some dust on the pantry items.
beenthere is offline   Reply With Quote
Old 02-12-2012, 06:20 AM   #20
Member
 
Join Date: Dec 2011
Posts: 108
Default

Uneven temps - Solutions? Looking for advice/opinions


Quote:
Originally Posted by beenthere View Post
Could leave you with some dust on the pantry items.
So otherwise - it looks like a good plan?

Luckily - The new pantry return would be directly in front of the door. Hopefully I wont need to worry about that.
fuzzball03 is offline   Reply With Quote
Old 02-12-2012, 06:21 AM   #21
An old Tradesmen
 
Join Date: Oct 2008
Location: PA
Posts: 24,527
Default

Uneven temps - Solutions? Looking for advice/opinions


Shouldn't be a problem. Its not something that is commonly done.
beenthere is offline   Reply With Quote
Old 02-12-2012, 10:00 AM   #22
Member
 
Join Date: Nov 2011
Posts: 298
Default

Uneven temps - Solutions? Looking for advice/opinions


If you could, remake the drawing with your changes shown. again, I would suggest, as others have, getting rid of the flex duct and going metal. The piece of this your maybe missing is the science and math behind the duct work sizes and design. thus my suggestion that you have a new duct system designed.

as to the returns, my understanding is that more is better!!! The ulitmate design, for the best comfort etc is....

1. properly sized and located supply in each room. CFM designed for the cubic size of the room and the orientation of the room with respect to heat gain from the sun.

2. a return in each room.
3. damper in each supply so that balancing can be preformed.
4. each register grill must be matched to the flow and throw required for each room.
5. total system equivilant lenght and static pressure. low static pressure can really save you money!!
thus the design, as you can see is very detailed. From your posts, it seams that you really want to do this right. so for that I say get a professional to design your duct system. after that you of course can make the changes. Its hard work and not easy, but once the design is done, the rest if well withing the grasp of a DIY person. . I suggest reading up on manual d!!!!
bobinphx is offline   Reply With Quote
Old 02-12-2012, 11:45 AM   #23
HVAC Tech/ Browns Fan
 
Join Date: Dec 2009
Location: Dayton, ohio
Posts: 541
Default

Uneven temps - Solutions? Looking for advice/opinions


Is that a true blue print of your house and duct run's. If so vents should be by window's then returns by the doors. If you look vents are by the door (if that is true blue print ) then when the air comes out it going straight out the hall way or door.
Tator1076 is offline   Reply With Quote
The Following User Says Thank You to Tator1076 For This Useful Post:
plummen (02-12-2012)
Old 02-12-2012, 11:46 AM   #24
HVAC Tech/ Browns Fan
 
Join Date: Dec 2009
Location: Dayton, ohio
Posts: 541
Default

Uneven temps - Solutions? Looking for advice/opinions


Plus if anything some rooms should have two vents then one of them
Tator1076 is offline   Reply With Quote
The Following User Says Thank You to Tator1076 For This Useful Post:
plummen (02-12-2012)
Old 02-12-2012, 03:02 PM   #25
Member
 
Join Date: Dec 2011
Posts: 108
Default

Uneven temps - Solutions? Looking for advice/opinions


Quote:
Originally Posted by Tator1076 View Post
Is that a true blue print of your house and duct run's. If so vents should be by window's then returns by the doors. If you look vents are by the door (if that is true blue print ) then when the air comes out it going straight out the hall way or door.
Quote:
Originally Posted by fuzzball03 View Post
Yes, it's almost dead on.
I've been told that they SHOULD be near the greatest heat loss area. Windows, door, outside walls, etc
The exact bends are actually not show - but side of box, then run to vents are placed accordingly.

The scaling should be exact and true(I lost approx 37 sq ft in the whole house when doing some scaling and math to get room area - checked it with a tape measure, within 6" for each room/area)

Last edited by fuzzball03; 02-12-2012 at 03:11 PM.
fuzzball03 is offline   Reply With Quote
Old 02-12-2012, 03:10 PM   #26
Member
 
Join Date: Dec 2011
Posts: 108
Default

Uneven temps - Solutions? Looking for advice/opinions


Quote:
Originally Posted by bobinphx View Post
If you could, remake the drawing with your changes shown. again, I would suggest, as others have, getting rid of the flex duct and going metal. The piece of this your maybe missing is the science and math behind the duct work sizes and design. thus my suggestion that you have a new duct system designed.

as to the returns, my understanding is that more is better!!! The ulitmate design, for the best comfort etc is....

1. properly sized and located supply in each room. CFM designed for the cubic size of the room and the orientation of the room with respect to heat gain from the sun.

2. a return in each room.
3. damper in each supply so that balancing can be preformed.
4. each register grill must be matched to the flow and throw required for each room.
5. total system equivilant lenght and static pressure. low static pressure can really save you money!!
thus the design, as you can see is very detailed. From your posts, it seams that you really want to do this right. so for that I say get a professional to design your duct system. after that you of course can make the changes. Its hard work and not easy, but once the design is done, the rest if well withing the grasp of a DIY person. . I suggest reading up on manual d!!!!
I appreciate the good points.
1 - Now that I have heat gain/loss, I'm looking into doing this. I may oversize in the Master Bedroom(200-500 BTUs), and the office(1,000 BTU per HVAC calc).
2- Think this isnt practical in my case, but i seriously considered it. House is very open concept; heat gained from separate returns; then the location of my return would make this very difficult.
3 - If I redo any duct runs(I probably will), then they will get a damper.
What do you think about orienting my Dist. Box in the attic at a 45' to help or eliminate any harsh angles from the plenum(currently a 90') as well as to the supply's?
4 - Also looking into that in conjunction with #1. Seems to be a huge issue for at least 2 rooms already with current ducting.
5 - Wish I knew more about the correct design to do this. I understand the physics of what static pressure can do, but not enough about air distribution to create a much lower pressure. Hiring a professional may be a good choice.
Any Dallas area recommendations for professionals?

edit: I'll remake the drawing here shortly for the 'future' plan.
fuzzball03 is offline   Reply With Quote
Old 02-12-2012, 06:49 PM   #27
Member
 
Join Date: Nov 2011
Posts: 298
Default

Uneven temps - Solutions? Looking for advice/opinions


[quote=fuzzball03;851627].
What do you think about orienting my Dist. Box in the attic at a 45' to help or eliminate any harsh angles from the plenum(currently a 90') as well as to the supply's?



You are there and I cant see the "actual" design. unless you want to take and post some pictures. I cant be sure of any suggestions that I would make. Of course, you have to understand that I am no expert, others here are and I think pics would really help that question.

now if you pushed me for an answer, I would say that I dont like plenum systems and I dont like flex ducts. I would much rather have a steel central duct with takeoffs. But in your case, I would think that pulling the flex tight and replacing the 90's and 45's with metal elbows would really really help you. Now understand, I would consider this a compromise. I certainly could be wrong.

At this point, if I was you, I would suggest maybe this site for a 30 day download if what looks to be a pretty good design software. It might even help to pinpoint what upgrades you could make to the existing system.
http://www.designmaster.biz/products.../pressure.html
bobinphx is offline   Reply With Quote
Old 02-13-2012, 05:25 PM   #28
Newbie
 
Join Date: Feb 2012
Posts: 1
Default

Uneven temps - Solutions? Looking for advice/opinions


static pressure issue. zoning your system along with blower speed adjustment will correct problem
HVACDOK is offline   Reply With Quote
Old 02-14-2012, 08:21 PM   #29
Member
 
Join Date: Dec 2011
Posts: 108
Default

Uneven temps - Solutions? Looking for advice/opinions


Quote:
Originally Posted by HVACDOK View Post
static pressure issue. zoning your system along with blower speed adjustment will correct problem
Hey there,
Thanks for the reply.
Would you mind giving me any more info as on how you came to your conclusion?

fuzzball03 is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
re-pointing chimney in low temps bubbler Building & Construction 5 10-07-2011 12:38 PM
my uneven floors are making my doors uneven fundaqueens Windows and Doors 4 05-04-2011 09:00 PM
Uneven sub-floor issue in basement - SOLUTIONS? swanson Flooring 0 07-13-2010 07:52 PM
Return/Supply temps honola HVAC 1 09-29-2009 04:35 AM
Wet basement, uneven floor - what's the best flooring? pepsigirl Flooring 1 05-16-2009 07:36 PM




Top of Page | View New Posts

Copyright © 2003-2014 Escalate Media. All Rights Reserved.