Return to the Heating & Air Conditioning Forum | Post a Follow-Up

 o
Replacing 25 yr old Trane XR800 2 ton - Need advice

Posted by jpinsonjr (My Page) on
Tue, Mar 13, 12 at 13:40

Central Arkansas, mild winters hot humid summers
Replacing upstairs Trane XR800 8 seer unit that is 25 years old.
1100 square foot upstairs,
Installed in the attic

Manual J - shows a need for 16,000 btu and 1.4 tons cooling at 70% SHR and 1.2 at 80% SHR. If I am reading this correctly

I have been quoted the following

TDHIB040A9241A - 95% furnace/40,000 BTU
4TXCB025BC - 2 Ton Cooling
4TTR5024 - 2 Ton Condensing Unit, 15 Seer XR15
1-TCON 800 programable thermostat

Total cost $4999.00 plus tax. Not counting local utility rebate of $600 for the 95% or higher furnace.

One year free service,
10 yr warranty on Compressor, cooling coil. Furnace heat exchange - lifetime

All prices include installing new aux drain pan with float switch, new outdoor concrete pad, flushing lines, new return plenum, and bringing the service platform up to code.

My concerns are humidity. I am afraid that this will cool too quickly and not resolve humity.
Is the furnace to large?
I have heard some concerns about putting a high effenciency heat unit upstairs in the attic. Some say there is issue with the unit freezing.

Does this make sense?


Follow-Up Postings:

 o
RE: Replacing 25 yr old Trane XR800 2 ton - Need advice

Quote is for Trane equipment


 o
RE: Replacing 25 yr old Trane XR800 2 ton - Need advice

40k btu furnace is the smallest furnace they make. no problem there. 95% furnace for your area is overkill but with a rebate of $600 hard to argue with. Size of the a/c is probably ok. assuming the load calc was done completely correct 1.5 ton unit would work but bad to find out on 100 degree week that someone did a half way job on your load calculation. being in a hot humid climate and being it is the upstairs unit (heat rises) run time should be long enough to dehumidify. I would bring up your concerns about humidity with your contractor because he can better look at your paticular situation.


 o
RE: Replacing 25 yr old Trane XR800 2 ton - Need advice

A heating load of 16,000 BTU sounds low. What are the typical low temperatures in the winter?

Will the furnace be in conditioned space? If not, then my concern would be freezing condensate. I have read heat tape can be used to prevent freezing. Ask the contractor what he plans to do for the installation.


 o
RE: Replacing 25 yr old Trane XR800 2 ton - Need advice

good price for sure. You might want to consider heatpump option since your winters are mild.


 o
RE: Replacing 25 yr old Trane XR800 2 ton - Need advice

neohioheatpump- In regards to the heat pump, are you talking about heat pump with natural gas or all heat pump. If all heat pump, the issue is the cost of running wiring for the heat strips.

mike_home - Winters can get low 20's and below.

harlemhvacguy - 105+ days occur. Not unusual to have 95-105 days with high humidity. Heat index upper 115-125 range.

Would a variable speed fan with a different thermostat make sense?


 o
RE: Replacing 25 yr old Trane XR800 2 ton - Need advice

Who performed the Manual J calculation? What winter and summer design temperatures were used?

Given the winter and summer temperatures you have reported, the heating and cooling loads seem low to me. Your equipment sizes are problably correct. You are not as oversized as you think your are.

A variable speed AC will help the high humdity you experience in the summer. You will want a good 2-stage thermostat for control.


 o
RE: Replacing 25 yr old Trane XR800 2 ton - Need advice

Manual J was done by a local Trane dealer.
Heating temp 20 degrees and cooling 98 degrees

I have recieved an updated price for the variable speed blower.

THD2B060A9B3VA - Priced increased $1150 and Seer increased to 16.

Which Thermostat would I need. I just want to make sure I can control humidity.


 o
RE: Replacing 25 yr old Trane XR800 2 ton - Need advice

I guess I thought the poster's climate was warmer. If they only get say 5-6 days of weather in the low 20's that might be worth getting by on just heatpump with electric strip backup. If they already have natural gas then maybe they should spend the extra money to have an 80% furnace. I really like the idea of the heatpump for their climate because there climate sounds like the winters are not too terrible and the heatpump could handle that well. Ofcourse natural gas furnace with a heatpump is always better. That is what I have. I really like the heatpump heat for the milder cold weather (35 and above).


 o Post a Follow-Up

Please Note: Only registered members are able to post messages to this forum.

    If you are a member, please log in.

    If you aren't yet a member, join now!


Return to the Heating & Air Conditioning Forum

Information about Posting

  • You must be logged in to post a message. Once you are logged in, a posting window will appear at the bottom of the messages. If you are not a member, please register for an account.
  • Posting is a two-step process. Once you have composed your message, you will be taken to the preview page. You will then have a chance to review your post, make changes and upload photos.
  • After posting your message, you may need to refresh the forum page in order to see it.
  • Before posting copyrighted material, please read about Copyright and Fair Use.
  • We have a strict no-advertising policy!
  • If you would like to practice posting or uploading photos, please visit our Test forum.
  • If you need assistance, please Contact Us and we will be happy to help.


Learn more about in-text links on this page here