Any HVAC guys out there

[KrisZ]

Originally Posted by 4WD
Speaking of humidity … two year old HVAC started dripping from secondary line. Dealer said no bleach.
Any of you guys use vinegar or hydrogen peroxide to treat the PVC line ?



Time to unclog the evaporator drain line. I would not use chemicals, but a manual method instead.

 

[ArrestMeRedZ]

Thanks for the info guys. I used it to purchase a new Trane 16 SEER HVAC system. The 16 SEER was about $1200 more than the 14 after the state rebate is included. With rough calculations, I figured the 16 would pay for it's increased cost over the 14 in energy savings in about 6 years at current electrical rates and outside air temps. Since the tendency is to "go green" at much higher electrical rates here, I think a 4 to 5 year payback is more realistic.

The Goodman 16 SEER was about the same price as the Trane 14 SEER installed, or about $1200 cheaper than the equivalent Trane. For the difference in price, and considering the eventual labor cost of replacement it was an easy decision to buy the better rated unit. Plus Trane is reportedly easier to work on.

Everyone here is amazed I got 21 years out of the existing Carrier builder's model. It is Vegas, and ACs get worked out here. I went with the same 5 ton rating with the new system. Well insulated 2000 sq ft single story house with low E windows and high ceilings. Seems like overkill, but with the original unit lasting that long I'm not about to change it. Plus with outside air temps reaching 115 degrees, it's nice to be able to maintain a nice low temp inside.

 

[dnewton3]

Your system is a 5-ton; hence it's nominal equiv is 60,000 BTU. Now it is "rated" for some value less than that, depending upon the indoor coil and air mover it's paired with. Most likely, it's true rating is somewhere around 56k to 58k BTU capacity.

A few pages back, my comment was "cool is cool". That is because temps are based on your system's ability to handle the heat load. Presuming your contractor did a manual J calculation, and he spec'd the right size unit, you should be fine. However, part of that calculation is based on what dT (temp delta) you input into the equation.

Let me give an examples for a 30 deg dT ...
If you assume a dT of 30 degF, then the system capacity will be able to handle anything less than the 30 degF and not run full time. However, if the OAT exceeds your desired IAT by more than 30 degF, your interior temp will rise. if it's 100 deg outside, and you want 75 deg inside, you're good because the dT is only 25 deg. But if it's 115 outside, then all it would be able to provide inside is 85 degF (115-30=85) !!!

Max system capacity is what holds the "cool" temp you want maintained IF AND ONLY IF you have enough capacity to overcome the worst case condition assumptions.
RH (relative humidity) is controlled by the factor of system ability to pull moisture out of the air; that's driven not only by coil size but also airflow, heat exchanger design, etc.
Being in LV, it's not like high humidity is a concern ... but "heat" (temp load) most certainly is.