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  #1  
Old 9/2/08, 8:26 PM
Brian E. Kelly's Avatar
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Default Hmmmm Low Delta T?????????

Can't even imagine why????????





For my next trick I will need a volunteer

ps some of the opinions I have posted here may or may not be factually based.




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Last edited by bkelly2; 10/13/08 at 8:09 PM.
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  #2  
Old 9/2/08, 8:44 PM
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Default Re: Hmmmm Low Delta T?????????

Ran into a similar situation last week. After moving a dead rat in a huge trap out of the way I saw where he had eaten thru the covering, the insulation and the inner duct to build a nest in a nice, cool section of the flex duct. You can't really see it in this photo but 50-70% of the conditioned air from that duct was being lost to the attic of this 1936 home.

Flex.jpg
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  #3  
Old 9/3/08, 8:15 AM
Brian A. MacNeish Brian A. MacNeish is offline
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Default Re: Hmmmm Low Delta T?????????

Quote:
Originally Posted by bkelly2
Can't even imagine why????????
Brian:

Did you check the temps of the cooled air before it moved past these points with deteriorated plastic covering. My thinking is that if the insulation was still fully intact with the inner air-carrying duct being air tight, the delta T still may be low from poorly operating/serviced AC unit.
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  #4  
Old 9/3/08, 8:33 AM
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Default Re: Hmmmm Low Delta T?????????

I had pretty much written off the HVAC before I got into the attic Brian, this was just one more nail in the coffin. Unit was original circa 1985.





For my next trick I will need a volunteer

ps some of the opinions I have posted here may or may not be factually based.




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Last edited by bkelly2; 10/13/08 at 8:09 PM.
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  #5  
Old 9/4/08, 12:37 PM
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Default Re: Hmmmm Low Delta T?????????

Quote:
Originally Posted by mboyett
Ran into a similar situation last week. After moving a dead rat in a huge trap out of the way I saw where he had eaten thru the covering, the insulation and the inner duct to build a nest in a nice, cool section of the flex duct. You can't really see it in this photo but 50-70% of the conditioned air from that duct was being lost to the attic of this 1936 home.

Attachment 23688
Michael, what are you doing moving personal property?



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  #6  
Old 9/4/08, 5:36 PM
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Default Re: Hmmmm Low Delta T?????????

I hate to start this but BK here goes anyway David A. is on vacation so let her rip take my pics of 72 degrees within the home and 55 degrees on the supply and move the delta T to 85 within the home and 67 degrees on the supply. What would you say about the system then???????
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  #7  
Old 9/4/08, 5:39 PM
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Default Re: Hmmmm Low Delta T?????????

Quote:
Originally Posted by cbottger
I hate to start this but BK here goes anyway David A. is on vacation so let her rip take my pics of 72 degrees within the home and 55 degrees on the supply and move the delta T to 85 within the home and 67 degrees on the supply. What would you say about the system then???????
Nice try Charley, but not enough info.

But if it has not been serviced in the last year, they better have a HVAC contractor out there to check it out.

I do not like the dirty rusty registers either.





For my next trick I will need a volunteer

ps some of the opinions I have posted here may or may not be factually based.




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  #8  
Old 9/4/08, 5:39 PM
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Default Re: Hmmmm Low Delta T?????????

Working good Charley----

Yep....you're damn lucky David is on vacation----------------
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Old 9/4/08, 5:43 PM
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Default Re: Hmmmm Low Delta T?????????

Quote:
Originally Posted by bkelly2
Nice try Charley, but not enough info.

But if it has not been serviced in the last year, they better have a HVAC contractor out there to check it out.
For what?-----------------

Oh my, you and OUR court system seem to have you gun-shy----
---

Me too, actually-------
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  #10  
Old 9/4/08, 6:00 PM
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Default Re: Hmmmm Low Delta T?????????

Quote:
Originally Posted by bkelly2
Nice try Charley, but not enough info.

But if it has not been serviced in the last year, they better have a HVAC contractor out there to check it out.

I do not like the dirty rusty registers either.
Come on Wuss what more do you need put those temps on any unit that you have looked at.



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  #11  
Old 9/4/08, 6:02 PM
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Default Re: Hmmmm Low Delta T?????????

Quote:
Originally Posted by cbottger
Come on Wuss what more do you need put those temps on any unit that you have looked at.

Ah therein lies the rub Charley, I haven't looked at that unit now have I?

And the register is still dirty and rusty.





For my next trick I will need a volunteer

ps some of the opinions I have posted here may or may not be factually based.




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  #12  
Old 9/4/08, 6:03 PM
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Default Re: Hmmmm Low Delta T?????????

Quote:
Originally Posted by dduffy
Working good Charley----

Yep....you're damn lucky David is on vacation----------------
You got that right I am sure I will catch hell for this



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freedomexpressinspections.com
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  #13  
Old 9/4/08, 6:12 PM
Charley L. Bottger's Avatar
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Default Re: Hmmmm Low Delta T?????????

Quote:
Originally Posted by bkelly2
Ah therein lies the rub Charley, I haven't looked at that unit now have I?

And the register is still dirty and rusty.
Don't want to rub you and don't care about the dirt and rust you are avoiding the subject



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freedomexpressinspections.com
freedomexpress495@att.net
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Okla. State DEQ Environmental Phase One Certified
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  #14  
Old 9/8/08, 7:20 PM
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Default Re: Hmmmm Low Delta T?????????

Quote:
Originally Posted by cbottger
the delta T to 85 within the home and 67 degrees on the supply. What would you say about the system then???????
...this is unhealthful to my delicate psyche



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  #15  
Old 9/8/08, 8:57 PM
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Default Re: Hmmmm Low Delta T?????????

Quote:
Originally Posted by cbottger
..take my pics of 72 degrees within the home and 55 degrees on the supply and move the delta T to 85 within the home and 67 degrees on the supply. What would you say about the system then???????
Based on my limited knowledge & training I would let the system run for 12-15 minutes and if the room temp was coming down to say 82 or so then to 80 I would call the system operating properly with a delta T of around 18°. Now, I'm sure that's the wrong answer so feel free to berate me and inform me of my shortcomings...maybe we will all learn something.
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