Desperate questions from a father of three sweaty youngin's (and one sweaty wife)

[Wheelbaron]

Call them back(the installing co) and ask them a few questions:
Did they do a load calculation on the building?
Did they check the duct sizing of the system at all?

For your part, did you look for the best contractor, or just the cheapest? (just asking)


If the evaporator is freezing up, it will cause the symptoms that you speak of. However, do not expect the new system to "blow harder" than the old system. If the system is set up properly, there should be as little noise, and air speed as possible while delivering comfort. Also, set the fan switch on your thermostat to On instead of AUTO.

[Oldschoolmetal]

I wouldn't necessarly agree. What is the load of the house, are there lots of windows, good insulation in the attic, walls? is the basement completly under ground or only partly underground, what was the size of the origonal equipment and most importantly was a Manual J performed before the installation was Started. Are there trunk dampers to adjust the air flow from one floor to the next for summer/winter that the tech may have adjusted improperly? I would agree with Stamos.

Even in Phoenix when I was working down there last summer sized systems @ 600 SQ. FT per ton average. It was only 115 degree everyday. 500 is over sized. If you have that many windows wide open to the sun, you better invest in some blinds.

[Tinner32]

pls post pix of sweaty wife......

Dude that was awesome!!!

[Thurmont HVAC]

Even in Phoenix when I was working down there last summer sized systems @ 600 SQ. FT per ton average. It was only 115 degree everyday. 500 is over sized. If you have that many windows wide open to the sun, you better invest in some blinds.

I hear ya. On the East coast mid atlantic region, We had to move away from the 600Sq ft rule of thumb, It kept getting the Co. I used to work for in trouble, now days is strickly Manual J. Around here seems most people want those great big firggin windows,tall ceilings and cut up rooms with no shading or Blinds, some get defensive at the mere suggestion of actually putting up some kinda blinds !! Now days when I'm doing my loads one of my questions to my potential client is "do you plan on having window shading or blinds" 115 degree days!! I bet Attic's are just a bowl full of Joy down there!!!

[Oldschoolmetal]

Thrumont,
Does it get that hot in Maryland ? I had fun in Phoenix, I plan on moving back this next spring.

[Thurmont HVAC]

Not 115 deg. Hot but some years August can be around 100-102 deg for a good portion of the month, but for the most part it's Humid as Hell from late may to September.

[Oldschoolmetal]

I hate the humidity. I was down in Virginia this time of year going threw school and it was like 90 to 100% humid back in 92.

[Diceman]

You can't assume the tech knows what he is doing.
He might, but............

[tinner73]

5 tons for 2500 sq ft.

NOT GOOD!!

did salv97 size it for you??

[genduct]

To answer your question directly, Yes the tech was right, when you closed off the two easy paths for the air to go, you reduce the airflow to the point where the coil froze!!!!!
Closing the Bstm ters sounds logical but it doesn't work begause the resitandce in the duct for the rooms that are not being served is too much for the pressure in your fan to overcome.
You need someone who understands duct design/sizing to help you. too bad the istaller didnt seem to be that person.

[genduct]

PS the 5 ton unit means that you need to move even more air and hence the small duct system was even more challeneged