On The Fence - 2.5 ton v. 3 ton Heat Pump - HELP

[luckygamer]

We have a 3-level 2400 sq. ft. townhouse in Maryland and need to replace the heat pump & indoor air handler. Currently have a 2.5 ton unit, but don't always feel optimal temp on upper level.
Salesperson initial recommendation was a 2.5 ton, but on further discussion said could be OK with 3 ton unit if we added an addition return in the finished basement. Said it was needed because existing cold air return could not handle volume generated by 3 ton unit. Would it negate the benefit of having a 3 ton by ADDING a cold air return? Will it lower the efficiency to do that?

Don't want to overbuy because I'm told that can cause other problems, but I am willing to spend to maximize the potential efficiency. I'm not sure if the salesperson is just trying to appease me.

We're deciding between TRANE XL14i (2.5) XL16i (3.0).
Any aid/insight would be much appreciated!

[tigerdunes]

luckygamer

A couple of questions.

Has your dealer provided a heat/cool load calculation? Insist on this,get it in writing and carefully review with your dealer.

If you go up in size from a 2.5 ton to a 3 ton, you need to verify that your ductwork is sized for the upsize. Has your dealer made inspection of your ductwork? You should mention possible airflow issues on upper level. Ductwork should be inspected as to size, insulation properties, overall condition, supplies and returns.Supply air and return air should be in balance. I see nothing wrong in adding a return but I would ask dealer to see his calculations. A 3 ton unit would require ductwork that can handle 1200 CFMs of air.

The XL16i Trane heat pump is a great system but so is the XL14i. Keep in mind that that the XL14i comes in 3 ton size-it's just not as efficient as the XL16i with its 2 stg compressor.

IMO

[BaldLoonie]

Often a bigger unit will cool the downstairs faster and shut off, leaving the upstairs even warmer! The smaller unit runs longer, which means more even temps and lower humidity. With 2 stage, that isn't the issue like it is with a single stage.

[RoBoTeq]

Capacity of cooling is not your problem, therefore increasing the capacity will not solve your problem.

Your problem is distribution, and that can be a bit trickier. If anything, I would be looking at getting more return to the uppermost level of the home.

If there is a choice of slightly oversizing or slightly undersizing; I will go undersized.

[allant10]

A lot of townhouses that I see have trouble with the upper levels not getting enough airflow. This usually is because the unit is located in the basement and you are trying to push air up three levels in some cases. Getting a larger system is not going to help that problem. If your system needs to be replaced I would insist on having a contractor do a heat loss/gain on your home to see what size system you truely need. You may want to ask about a booster fan to help push the air up the ducts to the upper level.

[bryguy]

I live in a townhouse in MD, and very recently got a 3 Ton Trane XL16i Heat Pump installed by BGE HOME with the 4TEE3F40A air handler. (EXTREMELY PROFESSIONAL SERVICE if I may say so!!)

I used to have a 2.5 ton "comfortmaker" system which lasted 19 Years!!!(The original unit which came with our townhouse)
It finally gave up the ghost this year and after MUCH soul-searching ( and price shopping), I upgraded to the very excellent Trane system...

I could have gotten a Goodman or Rheem or something like that for a LOT less money, but I figured "what the heck"... I might as well get something I like. ( I have to admit, it was the FREE Promotional 10 Year parts AND labor warranty that sold me on this...)

IT IS AWESOME!!! I can cool my house down in 15 minutes now, which used to take 1-2 hours... LOW HUMIDITY TOO!!
The VS air handler runs on low, (very low, asolutely NO NOISE) speed most of the time,but if you are out of the house for a long time, and come back to a hot house and want to cool things down in a hurry... WOW!!! Speed #12 kicks in and its like living in Alaska for a while until the indoor temp. reaches "setpoint" then things slow to a crawl again..

I HEARTILY RECOMMEND THE 3 TON UNIT WITH THE VARIABLE SPEED AIR HANDLER vs the 2.5!!!

I also just received my Electric bill. $98.00 and we have run our new system EVERY DAY in the last 2 months...
An "old" electric bill would have been $150-$180 for the same period... UNBELIEVABLE!!!!


P.S. Following the install, the technicians took me outside to check the compressor, and I thought it was BROKEN... Find out that I had to get within 10-15 feet of it to even BEGIN to hear it...
The old COMFORTMAKER could be heard running a block away even when new...

I almost can't wait for winter to see how this unit performs... NOT!!!! LOL

[Edited by bryguy on 07-06-2006 at 04:31 PM]

[danglerb]

Nothing like that new car smell, but 2.5 vs 3 ton isn't Africa and Alaska, nor does it address top to bottom cooling issues.

I am sure I will be happier for you "after" I get my new system, still sweating and waiting on condo association approval. Two stage compressor does sound tempting, but I have too short of a season to justify it. Maybe I should consider it anyway.

Isn't it pesky to get your electric bill every week (that can't be by the month ;).

[bryguy]

Yes, that IS my monthly Electric bill. (The installers said my old system was a 6-8 SEER... the new is a 17.0 SEER)

I dont think its the 2.5 vs 3.0 ton that makes the BIGGEST difference, rather its the INCREASED air-flow from the VS air handler that seems to make the system so much more impressive...

Also, the 2-stage compressor isnt just for the Cooling season ... It can be beneficial in the winter too? Right?

[danglerb]

My electric is over $200 without AC, with it I find it better not to look in the envelope.

VS blower isn't higher flow, its whatever flow the installer sets, same as a conventional blower except the VS can adjust the power level to keep the flow rate the same even with a dirty filter etc. VS also supports the lower speed requirements of stage one etc. Not sure if it varies from brand to brand or anything, but I have seen references to 350 cfm and 400 cfm per ton as common for installers to setup the blower.

I think so, winter you get choice of a little heat or a lot.

[mjk_na]

:)

Go with Manual J, and size your ducts according to Manual D. You'll be fine.

[xv80satisfiedcust]

Also, the 2-stage compressor isnt just for the Cooling season ... It can be beneficial in the winter too? Right?

I searched all over the Trane website for that question. I wouldn't be surprised if the XL16i was 2 stage cool, 1 stage heat ?????

[danglerb]

Trane site sure doesn't want to let out any secrets, but I noticed this in comparing the XL16i and 19i,

Two-Stage Operation (xl16i)One Compressor-Staged (xl19i)Two-Compressors

Also in the description of the XL19i it says 3 stage heating, nothing about stages of heat on the XL16i.

[dan sw fl]

Originally posted by luckygamer
We have a 3-level 2400 sq. ft. townhouse in Maryland and need to replace the heat pump & indoor air handler. Currently have a 2.5 ton unit, but don't always feel optimal temp on upper level.

Don't want to overbuy because I'm told that can cause other problems, but I am willing to spend to maximize the potential efficiency. I'm not sure if the salesperson is just trying to appease me.

We're deciding between TRANE XL14i (2.5) XL16i (3.0).
Any aid/insight would be much appreciated!

Bryguy gave you the answer you should concentrate on.

With increasing electric cost, I would install XL16i.

Can you install the new unit on the second floor?

[beenthere]

Can't speak for the Trane units but, York 2 stage is 2 stage in heat alos, until teh temp gets to 35 or40, depending on how we set it, the it runs in second stage every heating call.