Upgrading HVAC - Advice Please
I am a new member and came across this forum researching information to help me decide on what to do about our (inadequate) heating and cooling system.
There are some excellent posts and contributors and I hope to persuade you to give me your advice too.
We live in the D.C. Metro area in a 1920s single family home. Little to no wall insulation, new double-glazed windows, R19 attic insulation. Two original levels and a self-finished basement - 1200 square feet in the original levels.
Since moving here we have always struggled to get the house warm enough in winter or cold enough in summer. Current equipment:
Outside is a Trane XB1000 (TTB024C100A2)
In attic is a Trane XL 80 (TUD060R936H4) and control unit on the cooling blower(?) is a White Rodgers model 50A51-495.
Room temperatures are uneven and I think we have a balance problem with the airflow. I have closed the volume dampers (?) in the attic to lines for the small rooms that get too much heat or cold. We have two intakes, ceiling mounted, one on each of the original floors (14 x 14 served by 10" duct to the atic).
First floor has electric heated floors that keep toes warm but do not heat the rooms well enough in winter. The finished basement has electric baseboard heating and no air conditioning (rarely gets too hot and we have used a portable system on really hot days).
I have approached 3 highly rated contractors from Angie's List to hear their assessments: two have visited so far and I have one quote.
No Manual J calculations.
The contractor that has quoted recommended increasing the intake airflow by expanding the second floor intake and extending the first floor intake to low down on one wall. While inspecting the attic installation he adjusted the fan setup (it has color-coded pins) and showed how increasing air flow in would cause more air to flow from the registers. Their quote is also for replacing the system with Carrier equipment and doing the additional work:
-- Carrier 24ABB330 air conditioner (2 �-tons R410 @ 13 S.E.E.R.) with a Carrier CNPHP3617 3-ton horizontal coil
-- Carrier 58CVA070-12 2-stage gas furnace (Hi: 66,000 / Lo: 44,000 B.T.U.H. @ 80% A.F.U.E.)
-- Modify intakes as per above, plus refigerant lines, pad etc.
Total just less than $8000 (plus tax presumably).
For $500 I could upgrade further to a Carrier 24ACC630A air conditioner ( 2 �-tons R410 @ 16 S.E.E.R.) that would qualify for tax credit.
This seems a lot given that none of the duct work (except that related to the air intake) is going to be touched.
A final complication: we want to extend our house as the children grow and I was hoping to not have to upgrade the HVAC again. It may be that I will need a second complete system but that seems untidy and probably will be inefficient (an extension will not be self-contained).
Thank you for bearing with me so far. My questions:
-- Is it possible to calculate air flow in to determine better if that is a potential factor?
-- Is this Carrier system a good fit (notwithstanding no Manual J calculation)?
-- Any comments on the price?
-- Any ideas for upgradeable systems?
I am ignorant too about heat pumps and whether they are advisable and viable in my situation. Thoughts?
Thanks in advance.