Hello, experienced masses....

I am selling my home and have fixed everything that has been asked by
the prospective buyer and the city so far but am having difficulty
with the buyer's inspector in regard to his A/C performance spec.

The inspector told buyer that the temp drop from return vent to
evaporator test point was 10 degrees. The buyer was told that my A/C
system isn't performing as it should. I verified his finding of 10
degree drop after they left with MY thermometer. I'm not arguing his
number or his method. Please read on to see what I AM arguing about
(to myself).

The temperature outside at that time was only 75 F. and relative
humidity was 70%. This is a pretty cool day for St. Louis in July.
It was also overcast with virtually no sun. It was only 10 Oclock am
and with no sun load, the house was quite cool. My probe-style
thermometer read 68 degrees on my kitchen counter and in the return
air duct. I think its accurate within 1-2 degrees. I believe it to
be relatively accurate in terms of temperature differential, atleast.
So as stated previously, I put the thermometer in the same test point
as the inspector did with the system running and got 58 degrees. The
magic delta figure to fail a system and scare a buyer seems to be
below 15 - 17 degrees from what I've gathered in talking to realestate
agents and dealing with several home inspections. But don't you have
to take into consideration the temp and humidity and solar load to
some extent before interpreting delta temp?

I just happened to have an A/C company out two weeks ago to give my
system a performance test so I would be armed with a professional
opinion on paper before negotiations started. This is because the
previous owner had several big dogs, and apparently their big bladders
found the warm condenser fins a common target. (I was told that dogs'
urine is a common cause of condenser fin errosion). The missing fins
in one lower corner area coupled with some rust on the thin cage that
protects the condenser make the outside unit appear old and worn to be
sure. It isn't a great selling point visually. But this house isn't
the fricken' Taj Mahal either. I don't feel that someone can use the
APPEARANCE of my A/C unit to demand $2000+ for a new one IF IT WORKS!

The A/C guy I hired wrote that the temp change was 18 degrees,
pressures were normal and that 'system was operating normally at this
time'. It was about 85 degrees out and sunny that day and he did the
work around 2 pm. I tested the temp drop several days before he came
out and actually got 21 degrees but I can't remember the temperature
or sun condition then.

So how do you all feel about the accuracy of DELTA for the purposes of
condemning an A/C system? Do I really have a problem? Or may the
inspector have seen that the unit was around 15 - 20 years old with
fin damage and just found an easy way to condemn it that isn't
accurate? (much less than 5% fin damage)

I feel that for my 900 sq ft house with full basement (all cooled with
ductwork) and poor insulation my electric bills are reasonable. I
also feel that the A/C FEELS cold and the system has never been
charged in my 8 years here. I mean, 58 degree temp in the furnace
ductwork can't be that bad can it?

I thank you all for any responses yay or nay!!!

Tony

From: (ComboverFish)


Hello, experienced masses....

I am selling my home and have fixed everything that has been asked by
the prospective buyer and the city so far but am having difficulty
with the buyer's inspector in regard to his A/C performance spec.

The inspector told buyer that the temp drop from return vent to
evaporator test point was 10 degrees. The buyer was told that my A/C
system isn't performing as it should. I verified his finding of 10
degree drop after they left with MY thermometer. I'm not arguing his
number or his method. Please read on to see what I AM arguing about
(to myself).

The temperature outside at that time was only 75 F. and relative
humidity was 70%. This is a pretty cool day for St. Louis in July.
It was also overcast with virtually no sun. It was only 10 Oclock am
and with no sun load, the house was quite cool. My probe-style
thermometer read 68 degrees on my kitchen counter and in the return
air duct. I think its accurate within 1-2 degrees. I believe it to
be relatively accurate in terms of temperature differential, atleast.
So as stated previously, I put the thermometer in the same test point
as the inspector did with the system running and got 58 degrees. The
magic delta figure to fail a system and scare a buyer seems to be
below 15 - 17 degrees from what I've gathered in talking to realestate
agents and dealing with several home inspections. But don't you have
to take into consideration the temp and humidity and solar load to
some extent before interpreting delta temp?

I just happened to have an A/C company out two weeks ago to give my
system a performance test so I would be armed with a professional
opinion on paper before negotiations started. This is because the
previous owner had several big dogs, and apparently their big bladders
found the warm condenser fins a common target. (I was told that dogs'
urine is a common cause of condenser fin errosion). The missing fins
in one lower corner area coupled with some rust on the thin cage that
protects the condenser make the outside unit appear old and worn to be
sure. It isn't a great selling point visually. But this house isn't
the fricken' Taj Mahal either. I don't feel that someone can use the
APPEARANCE of my A/C unit to demand $2000+ for a new one IF IT WORKS!

The A/C guy I hired wrote that the temp change was 18 degrees,
pressures were normal and that 'system was operating normally at this
time'. It was about 85 degrees out and sunny that day and he did the
work around 2 pm. I tested the temp drop several days before he came
out and actually got 21 degrees but I can't remember the temperature
or sun condition then.

So how do you all feel about the accuracy of DELTA for the purposes of
condemning an A/C system? Do I really have a problem? Or may the
inspector have seen that the unit was around 15 - 20 years old with
fin damage and just found an easy way to condemn it that isn't
accurate? (much less than 5% fin damage)

I feel that for my 900 sq ft house with full basement (all cooled with
ductwork) and poor insulation my electric bills are reasonable. I
also feel that the A/C FEELS cold and the system has never been
charged in my 8 years here. I mean, 58 degree temp in the furnace
ductwork can't be that bad can it?

I thank you all for any responses yay or nay!!!

Tony


Why are you so worried? You fixed everything the city required. That's
different from the things the prospective buyers would LIKE you to fix for some
unknown deal where they've yet to tell you what they would LIKE to pay.

A simple "My asking price already takes that (the appearance and performance of
the unit) into consideration. You want a new unit? It'll raise the price. Lets
deal."

Or walk away.

You "FIXED" the system the AC guy listed his finding so the work has been
done and should not be a problem move on!

If they want it replaced or something tell them no and that is it!

Wayne


"ComboverFish" wrote in message
om...
Hello, experienced masses....

I am selling my home and have fixed everything that has been asked by
the prospective buyer and the city so far but am having difficulty
with the buyer's inspector in regard to his A/C performance spec.

The inspector told buyer that the temp drop from return vent to
evaporator test point was 10 degrees. The buyer was told that my A/C
system isn't performing as it should. I verified his finding of 10
degree drop after they left with MY thermometer. I'm not arguing his
number or his method. Please read on to see what I AM arguing about
(to myself).

The temperature outside at that time was only 75 F. and relative
humidity was 70%. This is a pretty cool day for St. Louis in July.
It was also overcast with virtually no sun. It was only 10 Oclock am
and with no sun load, the house was quite cool. My probe-style
thermometer read 68 degrees on my kitchen counter and in the return
air duct. I think its accurate within 1-2 degrees. I believe it to
be relatively accurate in terms of temperature differential, atleast.
So as stated previously, I put the thermometer in the same test point
as the inspector did with the system running and got 58 degrees. The
magic delta figure to fail a system and scare a buyer seems to be
below 15 - 17 degrees from what I've gathered in talking to realestate
agents and dealing with several home inspections. But don't you have
to take into consideration the temp and humidity and solar load to
some extent before interpreting delta temp?

I just happened to have an A/C company out two weeks ago to give my
system a performance test so I would be armed with a professional
opinion on paper before negotiations started. This is because the
previous owner had several big dogs, and apparently their big bladders
found the warm condenser fins a common target. (I was told that dogs'
urine is a common cause of condenser fin errosion). The missing fins
in one lower corner area coupled with some rust on the thin cage that
protects the condenser make the outside unit appear old and worn to be
sure. It isn't a great selling point visually. But this house isn't
the fricken' Taj Mahal either. I don't feel that someone can use the
APPEARANCE of my A/C unit to demand $2000+ for a new one IF IT WORKS!

The A/C guy I hired wrote that the temp change was 18 degrees,
pressures were normal and that 'system was operating normally at this
time'. It was about 85 degrees out and sunny that day and he did the
work around 2 pm. I tested the temp drop several days before he came
out and actually got 21 degrees but I can't remember the temperature
or sun condition then.

So how do you all feel about the accuracy of DELTA for the purposes of
condemning an A/C system? Do I really have a problem? Or may the
inspector have seen that the unit was around 15 - 20 years old with
fin damage and just found an easy way to condemn it that isn't
accurate? (much less than 5% fin damage)

I feel that for my 900 sq ft house with full basement (all cooled with
ductwork) and poor insulation my electric bills are reasonable. I
also feel that the A/C FEELS cold and the system has never been
charged in my 8 years here. I mean, 58 degree temp in the furnace
ductwork can't be that bad can it?

I thank you all for any responses yay or nay!!!

Tony

"Wayne" wrote in message
news:%6COc.188313$IQ4.136795@attbi_s02...


If they want it replaced or something tell them no and that is it!


No ****!!!

Been there done that, and the "prospective" buyer just kept wanting more and
more concessions.

Finally I hadda tell em to just go and find a different house.....ended up
they bought mine instead, as is.......

--

SVL

Thanks for your quick replies, guys. I know that I don't have to
repair the system. I know that the buyer is going to request doing so
for bargaining reasons, esp. since the house is in otherwise great
condition.

I actually hoped I could get a concensus on if my originally posted
Delta theory is wrong or right so I could be armed with some
experienced information. If I find out I'm right then I will be less
likely to budge on price 'just to get the deal done'. If I'm wrong it
would be nice to know also cause I hate the taste of crow!!!

To summarize my standpoint as a homeowner, I feel that $100 to $135 a
month for my electric bill is not out-of-line for the hottest three
months in St Louis with poor house insulation, many single pane
windows, and 1800 sq ft of space (half of it in the basement,
ofcourse) to cool. The elec. bill is about $25 - $50 the rest of the
season. Add to this that I feel the house gets comfortable and dry
and I have approx. 65 degree duct temp upstairs on hot days...

So, is everyone else paying less a month for electric? Is everyone
else getting 50 degree duct temps? Maybe I'm wrong. Maybe Delta temp
should always be 15 - 20 degrees no matter what temp it is outside.

Please jump in if you have an opinion! Thanks, Tony.





"HA HA Budys Here" wrote:
Why are you so worried? You fixed everything the city required.
That's
different from the things the prospective buyers would LIKE you to
fix for
some unknown deal where they've yet to tell you what they would LIKE
to pay.

A simple "My asking price already takes that (the appearance and
performance
of the unit) into consideration. You want a new unit? It'll raise the
price.
Lets deal."

Or walk away.


"Wayne" wrote in message news:%6COc.188313$IQ4.136795@attbi_s02...
You "FIXED" the system the AC guy listed his finding so the work has been
done and should not be a problem move on!

If they want it replaced or something tell them no and that is it!

Wayne

ComboverFish writes:

So how do you all feel about the accuracy of DELTA for the purposes of
condemning an A/C system? Do I really have a problem? Or may the
inspector have seen that the unit was around 15 - 20 years old with
fin damage and just found an easy way to condemn it that isn't
accurate? (much less than 5% fin damage)

That old, and performing poorly? It is simply worth next to nothing. Deal
accordingly.

Cf Proverbs 20:14

I think you are over concerned , your unit works. Either they buy the
house or they dont. Everybody wants a better price or deal or new AC ,
you dont have to do anything it is your house.

The "delta" method is valid during a limited time property inspection. A
properly working system should have a 15-18 delta. No higher than 20 or so.
High is no good, the evap will freeze up when the temp hits the dew point.

Dana,
General contractor, HVAC, Electrical, Plumbing, Certified CREIA home
Inspector
"Richard J Kinch" wrote in message
. ..
ComboverFish writes:

So how do you all feel about the accuracy of DELTA for the purposes of
condemning an A/C system? Do I really have a problem? Or may the
inspector have seen that the unit was around 15 - 20 years old with
fin damage and just found an easy way to condemn it that isn't
accurate? (much less than 5% fin damage)

That old, and performing poorly? It is simply worth next to nothing.
Deal
accordingly.

Cf Proverbs 20:14

On 31 Jul 2004 00:20:40 -0700, ComboverFish wrote:
Thanks for your quick replies, guys. I know that I don't have to
repair the system. I know that the buyer is going to request doing so
for bargaining reasons, esp. since the house is in otherwise great
condition.

I actually hoped I could get a concensus on if my originally posted
Delta theory is wrong or right so I could be armed with some
experienced information. If I find out I'm right then I will be less
likely to budge on price 'just to get the deal done'. If I'm wrong it
would be nice to know also cause I hate the taste of crow!!!

To summarize my standpoint as a homeowner, I feel that $100 to $135 a
month for my electric bill is not out-of-line for the hottest three
months in St Louis with poor house insulation, many single pane
windows, and 1800 sq ft of space (half of it in the basement,
ofcourse) to cool. The elec. bill is about $25 - $50 the rest of the
season. Add to this that I feel the house gets comfortable and dry
and I have approx. 65 degree duct temp upstairs on hot days...

Delta may be inaccurate if the compressor is kicking on/off automatically
in mild weather (not on 100% of time). Cooling capacity also depends upon
airflow and duct size. So the question is, does it have a history of
keeping you cool enough during hottest days of the year? The home is what
it is, so if they want you to replace something now instead of when it
becomes no longer functional, they should be willing to pay for it.

BTW my last electric bill (6/22) in northern IL was under $60.00 (572 kWh)
including a couple of PC's that run 24/7. But I just run a ancient wall
shaker downstairs or portable A/C upstairs when I need it, and box fan
exhausting from an upstairs window on mild nights. Most of my lights are
fluorescent, and blinds (and my neighbor's tree) limit solar gain.

--
David Efflandt - All spam ignored http://www.de-srv.com/

"ComboverFish" wrote in message
om...
Hello, experienced masses....

I am selling my home and have fixed everything that has been asked by
the prospective buyer and the city so far but am having difficulty
with the buyer's inspector in regard to his A/C performance spec.

The inspector told buyer that the temp drop from return vent to
evaporator test point was 10 degrees. The buyer was told that my A/C
system isn't performing as it should. I verified his finding of 10
degree drop after they left with MY thermometer. I'm not arguing his
number or his method. Please read on to see what I AM arguing about
(to myself).

The temperature outside at that time was only 75 F. and relative
humidity was 70%. This is a pretty cool day for St. Louis in July.
It was also overcast with virtually no sun. It was only 10 Oclock am
and with no sun load, the house was quite cool. My probe-style
thermometer read 68 degrees on my kitchen counter and in the return
air duct. I think its accurate within 1-2 degrees. I believe it to
be relatively accurate in terms of temperature differential, atleast.
So as stated previously, I put the thermometer in the same test point
as the inspector did with the system running and got 58 degrees. The
magic delta figure to fail a system and scare a buyer seems to be
below 15 - 17 degrees from what I've gathered in talking to realestate
agents and dealing with several home inspections. But don't you have
to take into consideration the temp and humidity and solar load to
some extent before interpreting delta temp?

I just happened to have an A/C company out two weeks ago to give my
system a performance test so I would be armed with a professional
opinion on paper before negotiations started. This is because the
previous owner had several big dogs, and apparently their big bladders
found the warm condenser fins a common target. (I was told that dogs'
urine is a common cause of condenser fin errosion). The missing fins
in one lower corner area coupled with some rust on the thin cage that
protects the condenser make the outside unit appear old and worn to be
sure. It isn't a great selling point visually. But this house isn't
the fricken' Taj Mahal either. I don't feel that someone can use the
APPEARANCE of my A/C unit to demand $2000+ for a new one IF IT WORKS!

The A/C guy I hired wrote that the temp change was 18 degrees,
pressures were normal and that 'system was operating normally at this
time'. It was about 85 degrees out and sunny that day and he did the
work around 2 pm. I tested the temp drop several days before he came
out and actually got 21 degrees but I can't remember the temperature
or sun condition then.

So how do you all feel about the accuracy of DELTA for the purposes of
condemning an A/C system? Do I really have a problem? Or may the
inspector have seen that the unit was around 15 - 20 years old with
fin damage and just found an easy way to condemn it that isn't
accurate? (much less than 5% fin damage)

I feel that for my 900 sq ft house with full basement (all cooled with
ductwork) and poor insulation my electric bills are reasonable. I
also feel that the A/C FEELS cold and the system has never been
charged in my 8 years here. I mean, 58 degree temp in the furnace
ductwork can't be that bad can it?

I thank you all for any responses yay or nay!!!

Tony

This is Turtle.

1) Checking the T.D. / Delta-T is not a very good test of the proformance of a
system for on high humitity day it will make the TD number look very poor and on
a dry day make the numbers look very good and it being the same system but at
different times. With the TD you can make a system look anyway you want it by
picking the time and days you want to check it. It sucks to check a system this
way.

2) Call all of them over to see the results of the TD but let the house get up
to about 95ºF or more in the house and then turn it on and you will have a 30ºF
to 35ºF [ TD ] . You can make the number what you want when choosing the time to
check it.

3) If you have a 58ºf discharge temperature and about 70ºf to 75ºf indoor
temperature. a TD of 10ºF or 15ºF can be just fine.

4) one for a thought. Take a brand new tune to perfection 14 seer hvac system
flower rater type and not expanion valve type evaperator coil and turn it on in
outdoor temperature of 50ºF and you will be luck as hell to get a 7 to 10ºF TD.
You need a low ambiant controller to get it to work in 50ºF or less outdoor
temperatures.

5) If your agent is going to use the TD to see if the system is working
properly you don't need a hvac professional at all and just get the yard boy to
check and turn up your system.

6) Using TD for a standard good test of a system is really just a joke talk
about.

TURTLE


---
Outgoing mail is certified Virus Free.
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Thank you very much for your inputs. Especially {David} about your
electric bill experience (that could point to my system being
inefficient) and {Dana} about delta value.

I wonder how cold an evaporator can actually get in a properly sized,
properly running home system? I thought 58 deg. was pretty good. I
am an auto mechanic; car systems are different enough that my
experience seems useless here -- Car evaps get down to just above
freezing and are positioned about 4 feet from the driver, though.

But if it turns out I'm paying way too much in electric that's all I
need to know. Then the system is running too long or simply
inefficient. I'll check with the neighbors and see what they're
paying....

Thanks,
Tony

ComboverFish writes:

I wonder how cold an evaporator can actually get in a properly sized,
properly running home system?

Don't confuse termperature with heat.

Great post, Turtle! This reinforces my theory that temp difference
can vary greatly. If the house is really hot when you turn the system
on, the evap is going to cool down relatively quick compared to the
house's ambiant temp. So to check delta a couple minutes after firing
up the A/C on a really hot day would probably yield some gawdy
number...
Thanks for the time and help, everybody!! (except alt.hvac
specifically -- try ignoring a post if you don't want to answer it --
it works better for everyone! That's why I wrote 'crosspost' in the
subject)


"TURTLE" wrote in message ...

This is Turtle.

1) Checking the T.D. / Delta-T is not a very good test of the proformance of a
system for on high humitity day it will make the TD number look very poor and on
a dry day make the numbers look very good and it being the same system but at
different times. With the TD you can make a system look anyway you want it by
picking the time and days you want to check it. It sucks to check a system this
way.

2) Call all of them over to see the results of the TD but let the house get up
to about 95ºF or more in the house and then turn it on and you will have a 30ºF
to 35ºF [ TD ] . You can make the number what you want when choosing the time to
check it.

3) If you have a 58ºf discharge temperature and about 70ºf to 75ºf indoor
temperature. a TD of 10ºF or 15ºF can be just fine.

4) one for a thought. Take a brand new tune to perfection 14 seer hvac system
flower rater type and not expanion valve type evaperator coil and turn it on in
outdoor temperature of 50ºF and you will be luck as hell to get a 7 to 10ºF TD.
You need a low ambiant controller to get it to work in 50ºF or less outdoor
temperatures.

5) If your agent is going to use the TD to see if the system is working
properly you don't need a hvac professional at all and just get the yard boy to
check and turn up your system.

6) Using TD for a standard good test of a system is really just a joke talk
about.

TURTLE


---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.732 / Virus Database: 486 - Release Date: 7/29/2004

"ComboverFish" wrote in message
om...
Thank you very much for your inputs. Especially {David} about your
electric bill experience (that could point to my system being
inefficient) and {Dana} about delta value.

I wonder how cold an evaporator can actually get in a properly sized,
properly running home system? I thought 58 deg. was pretty good. I
am an auto mechanic; car systems are different enough that my
experience seems useless here -- Car evaps get down to just above
freezing and are positioned about 4 feet from the driver, though.

But if it turns out I'm paying way too much in electric that's all I
need to know. Then the system is running too long or simply
inefficient. I'll check with the neighbors and see what they're
paying....

Thanks,
Tony

This is Turtle.

Tring to get a good ideal of electricity cost from a idenical system next door
to your is almost useless. You can change just one thing in the building of the
house and make your electric bill go way up or way down and insulation and
building materials go. Also the temperature setting of the thermostat and life
style of being there and not being there is a big thing. Everytime you open a
door to go out your adding to the cost operate the system. Just too many
variables to get a good ideal.

Now let's get picky here.

The 58ºF discharge air seems reasonible but anything colder seems to me to be a
restrictive air flow of the system. At 58ºF discharge air from the system puts
the evaperator coil at about 40ºF depending on the type system you have. So if
you had a 50ºF discharge of air would put your evaperator coil at or below
freezing. So here is my take on discharge air temperature in general on hvac
system.

57ºF to 65ºF is the normal range.
55ºF to 65ºF is normal on trailor houses only.
56ºF or below on houses and not trailor houses --- You have a problem somewhere
or you have a walk-in cooler and not a hvac system. Now if your asking for 60º
to 65ºF in the house you can get below the 56ºF discharge temperature a little
and still be normal.

Now to your auto discharge temp.s. 40ºF to 45ºF discharge air on 134-A is normal
and runs your evaperator coil at about 30ºF to 35ºF and also depends on the type
system you have.

Now using what i've said here to test a system --- Also sucks to , to compare it
working properly. There is really no sure fired way to check a system as to
working properly other than use super heat , run manual D , and have a real hvac
service man look at all the readings and give a report and TD is just a item to
confirm the real reading. TD is just for people to talk about when they don't
have a ideal as to what the system is doing.

TURTLE


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Outgoing mail is certified Virus Free.
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