Anyone have a rule of thumb for how cold the air from the register should
be? At the present the outside temp is 95 and the air out of the register is
50 deg. This sound about right. Thanks.

--
Paul O.

"Paul O." wrote in message
news
Anyone have a rule of thumb for how cold the air from the register should
be? At the present the outside temp is 95 and the air out of the register
is
50 deg. This sound about right. Thanks.

--
Paul O.



I've been checking the temperature at the last register to get air for many
years (try 27) and it has consistently run between 55-56. I'm no expert but
if it runs too cold I think that it may be an indication of low refrigerant.
Perhaps someone else can provide a better opinion.
MLD

It depends on the humidity inside the house, the CFM per ton of air
flow and the type of metering device (TXV or piston or cap tube) on the
indoor coil. Normally it is 16 degrees to 20 degrees below the return
temperature in the supply plenum just off the coil. The air will pick
up some heat traveling down the duct as well. 55 degrees is good, but
if your return temperature is 80 degrees, 60 degree supply air is more
likely. If it is very humid, the temperature could be higher still.



Stretch
(A/C contractor for 30 years)

"stretch" wrote in message
oups.com...
It depends on the humidity inside the house, the CFM per ton of air
flow and the type of metering device (TXV or piston or cap tube) on the
indoor coil. Normally it is 16 degrees to 20 degrees below the return
temperature in the supply plenum just off the coil. The air will pick
up some heat traveling down the duct as well. 55 degrees is good, but
if your return temperature is 80 degrees, 60 degree supply air is more
likely. If it is very humid, the temperature could be higher still.



Stretch
(A/C contractor for 30 years)

Thanks, appreciate the replies. Guess it's doing ok.
--
Paul O.

"Paul O." wrote in message
news
Anyone have a rule of thumb for how cold the air from the register should be?
At the present the outside temp is 95 and the air out of the register is 50
deg. This sound about right. Thanks.

--
Paul O.


This is Turtle.

Well i will tell you what the old rules was as to air temps 30 years ago and
today it is very much different.

Home Central air systems the temp will run between 55ºF to 65ºF discharge temp.s
depending on the temperature of the air in the house and has nothing to do with
the temp outdoors.

Trailor houses and other tight space cooling units can run down to 50ºF to 60ºF
discharge temp.

These are the old ways and the new equipment change these numbers up to a point
of these temp maybe different at to being real.

I will say this I really don't like the 50ºF discharge temp but you need to have
your system checked out to see for 50ºF temp just seems too low for my notion.

TURTLE

Stretch is right on.
You need a humidity gauge and thermometer to get the supply air and return
air temperatures so you can determine the split.
However, even then, you have no way to know what the airflow CFM is, so you
should have tech check your system.
The specific metering device also makes a difference. Always choose a TXV
over the other metering devices
Here is an old graph chart showing how humidity levels affect the temp-split
or temp-drop.
http://www.udarrell.com/air_temperat...evaporator.jpg

Check the outdoor condenser air temp-split. An old chart high split graph
probably NOT applicable to your A/C
http://www.udarrell.com/air_return_l...nser_split.jpg
- udarrell
--
Air-Conditioning Efficiency - "Optimizing evaporator Coil 'Heat-Load Btu/hr
first,' is critical"

http://www.udarrell.com/air-conditio...ator-coil.html

"stretch" wrote in message
oups.com...
It depends on the humidity inside the house, the CFM per ton of air
flow and the type of metering device (TXV or piston or cap tube) on the
indoor coil. Normally it is 16 degrees to 20 degrees below the return
temperature in the supply plenum just off the coil. The air will pick
up some heat traveling down the duct as well. 55 degrees is good, but
if your return temperature is 80 degrees, 60 degree supply air is more
likely. If it is very humid, the temperature could be higher still.



Stretch
(A/C contractor for 30 years)

On Fri, 20 May 2005 23:31:47 GMT, "Paul O."
wrote:

Anyone have a rule of thumb for how cold the air from the register should
be? At the present the outside temp is 95 and the air out of the register is
50 deg. This sound about right. Thanks.

The lower than normal temp and the fact that you are spending some
effort checking the temp and asking the question seems to indicate you
have a problem which you are not telling us. Is your house too hot?
Is your vent not blowing as hard as it used to?

JimL

Darrell, You have some interesting stuff in your possession! Stick
around buddy.


Stretch

"JimL" wrote in message
...
On Fri, 20 May 2005 23:31:47 GMT, "Paul O."
wrote:

Anyone have a rule of thumb for how cold the air from the register should
be? At the present the outside temp is 95 and the air out of the register
is
50 deg. This sound about right. Thanks.

The lower than normal temp and the fact that you are spending some
effort checking the temp and asking the question seems to indicate you
have a problem which you are not telling us. Is your house too hot?
Is your vent not blowing as hard as it used to?

JimL


No problem really, just got a hair to want to check the temp coming out of
the register and had no idea what it should be.
--
Paul O.

"stretch" wrote in message
ups.com...
Darrell, You have some interesting stuff in your possession! Stick
around buddy. Stretch

Thanks stretch
If I had some A/C work to do that I could no longer handle you would be at
the top of my list to contact.
You know far more than me; I have been retired way too long to be at your
level on the latest tech.
Glad to see you post all the normal causes of freeze-ups, I should have done
that instead of defending myself. Keep posting.
--
Air-Conditioning Efficiency - "Optimizing evaporator Coil 'Heat-Load Btu/hr
first,' is critical"

http://www.udarrell.com/air-conditio...ator-coil.html

"stretch" wrote in message
ups.com...
Darrell, You have some interesting stuff in your possession! Stick
around buddy.


Stretch


This is Turtle.

You know there is a bunch of everyday people in the hvac/r business in the
alt.home.repair here and have the real everyday thoughts and knowledge on hvac
or refrigeration. We could build a group to discuss real problems we see
everyday or work out hvac/r problems of even the posters. I see alt.hvac wants
only to discuss big topics of hvac or refrigeration and everyday problem are not
wanted there. I have seen some start but in just a little while the just get
discarded as '' well we will talk about it later '' for there is nothing big
here to discuss.

This is the place to discuss the little stuff that is really the business as a
whole and big topic is really just for Entertainment at alt.hvac. Here we would
not have to put on a show to what we know and just discuss a problem with no fan
fair. I have a bunch of things that happen that I would like to discuss but at
alt.hvac the group did not want to discuss it for the books did not explain it.

I think I will try out a thought on refrigeration in a post and see about a
discussion here at alt.home.repair. Watch for it.

TURTLE

Turtle, I like reading your posts - discussing various problems you have
experienced.
Any topic concerning hvac/r is good to go for me.

I know there are a lot of folks, due to their income, that simply have to go
with the lowest cost seer units.
They also need to keep their utility bills as low as possible, that is why
we and the government should do all we can for them.
If all systems worked to specs the amount of energy saved across America
would amaze you.
- udarrell
--
Air-Conditioning Efficiency - "Optimizing evaporator Coil 'Heat-Load Btu/hr
first,' is critical"
http://www.udarrell.com/air-conditio...ator-coil.html


"TURTLE" wrote in message
...

"stretch" wrote in message
ups.com...
Darrell, You have some interesting stuff in your possession! Stick
around buddy.


Stretch


This is Turtle.

You know there is a bunch of everyday people in the hvac/r business in the
alt.home.repair here and have the real everyday thoughts and knowledge on
hvac
or refrigeration. We could build a group to discuss real problems we see
everyday or work out hvac/r problems of even the posters. I see alt.hvac
wants
only to discuss big topics of hvac or refrigeration and everyday problem
are not
wanted there. I have seen some start but in just a little while the just
get
discarded as '' well we will talk about it later '' for there is nothing
big
here to discuss.

This is the place to discuss the little stuff that is really the business
as a
whole and big topic is really just for Entertainment at alt.hvac. Here we
would
not have to put on a show to what we know and just discuss a problem with
no fan
fair. I have a bunch of things that happen that I would like to discuss
but at
alt.hvac the group did not want to discuss it for the books did not
explain it.

I think I will try out a thought on refrigeration in a post and see about
a
discussion here at alt.home.repair. Watch for it.

TURTLE