"Travis Jordan" wrote in message
om...
noname wrote:
HVAC IsFun wrote:

An airconditioning system should provide an indoor environment of
approx. 15-20 f lower than the outside temperature at the time 'if'
it is properly sized and functioning correctly. The last poster
gave you a very good way to check the systems effectiveness . Do
that, and let us know. Keep in mind, that, if you have alot of heat
generating equipment in your apartment, then you may have increased
the cooling load beyond what the system is capable of .

So, if its 100f outside best I can hope for is 80?

What I used to get was 70 no problems. What if its 70 outside
shouldn't the air conditon get to 60 or less?

I think the PP meant to say that "an air conditioning system should
provide an indoor environment supply temperature of approx. 15-20 F
lower than the indoor return temperature at the time 'if' it is
properly sized and functioning correctly."



Umm..no..actually this is the first time I have seen Dave give correct
advice.
Mechanical Code, and Maunual J, T, and N, allows for a 20F design temp,
altho you can go higher, but the standard design IS a 20F delta between
outdoor and indoor.
However, IF you know that you will have a few days that are in the 100s, you
can allow for this. Degree days come into effect here. On average, depending
on your area, you wont have too many 100F days, unless of course, you are in
the southern half of the US....granted, heat waves hit the northern states
all the time, but unless its something odd, your 100F days up north are
much, much less than say..out in Southern CA where I learned the trade.
IF and this is IF your design temp is 20F and you have a 100F day, then you
might break say...76F indoors. Other factors come into play, and if the
system was not installed and designed correctly, then you might be fortunate
to keep it at 80F.
I might add, that in the case of the OP, I dont think hes got a design
issue, but either an install, or charge issue.
IF the guy that installed the outdoor unit didnt chck to see if the evap
coil was mated, or had a correct metering device for the new unit, nothings
really gonna help that issue till the evap issue is corrected.
Good money in this case, since no one can tell over the internet, and Daves
advice of checking delta T is NOT a great way to tell if you have a charge,
or an installation issue, would be on a bad charge....more than likely, if
anything, its slightly undercharged, and simply can not keep up the demand
with a higher load.
But...again...thats pure speculation.