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

 o
new build hvac advice

Posted by peony23 (My Page) on
Wed, Jan 15, 14 at 20:22

I was hoping the experts would weigh in and give me their opinions.

Our new build is in Maryland, single story 3400 sq ft, finished basement 1400 sq ft. We have 2x6 construction, upgraded insulation, good windows. We're on propane. HVAC recommended is Lennox 2 zone, 80K btu, 92% efficiency, 13 seer, 3 tons. Is this sufficient or is higher SEER and efficiency worth the added expense?

Thanks in advance.


Follow-Up Postings:

 o
RE: new build hvac advice

I would like to see some model numbers...

Since you are on propane, I would want higher furnace efficiency, two stage var speed plus add a high eff heat pump to help offset the expensive propane.

Now is not the time to go low end builder grade.

Not a fan of Lennox either.

IMO


 o
RE: new build hvac advice

Thanks, tigerdunes.

I don't have model numbers yet, just the general specs. The builder uses York for his higher efficiency systems. Do you like those any better? His thinking is they're all pretty much the same, but we know better.


 o
RE: new build hvac advice

Is the contractor proposing a single furnace and condenser with two zones, or two furnaces and two condensers?

Is the house 3400 sq. feet, or is it 2000 sq. feet plus a 1400 sq ft. finished basement?


 o
RE: new build hvac advice

Thanks, tigerdunes.

I don't have model numbers yet, just the general specs. The builder uses York for his higher efficiency systems. Do you like those any better? His thinking is they're all pretty much the same, but we know better.


 o
RE: new build hvac advice

Mike, there are 2 units, with the specs I've mentioned. Total 4800 sq ft.


 o
RE: new build hvac advice

Deleted....

This post was edited by tigerdunes on Thu, Jan 16, 14 at 16:02


 o
RE: new build hvac advice

For Tigerdunes,

The OP said this a 3400 sq. foot single story house.

"We have 2x6 construction, upgraded insulation, good windows"

This is better than typical construction. How much insulation will be in the attic?

The contractor is proposing 160K BTU heating and 6 tons for cooling. In my opinion this would be over sized for typical 2X4 construction and insulation in your climate. It is much over sized for what you are building.

Has the contractor done a load calculation? If so has he factored in the upgraded construction and insulation?


 o
RE: new build hvac advice

Tigerdunes, can you please repeat your recommendations for the heat pump/propane backup system? I'm talking to the builder about that setup, and it might be the one to go with. Thanks.


 o
RE: new build hvac advice

Because of the propane, you want top of line most efficient furnace possible.

While Lennox would not be my choice, I will assume you want recommendations for that brand.

SLP98v furnace up to 98% eff
XP21 heat pump
Best matching Lennox coil
Lennox thermostat
Filter box

I assume your home is being built over a crawlspace.

Rather than 2 systems, I would consider dividing home into 2 zones and use a zoning control for one system.

Insist on load calc both heating and cooling. Get it in writing. Assuming your home will have excellent building and insulation qualities, you definitely don't need 160 KBTUs of heating.

IMO


 o
RE: new build hvac advice

Thanks, tigerdunes. I started talking to the builder about a heat pump only after you mentioned it. So thank you. The house will be one-story but with a 40% finished basement, so 3400 1st floor, 1400 sq ft finished in the basement. We are planning 2 zones, but I'm don't understand your comment about zoning control for one system. We will get the load calculation you recommend, and the 160K BTU was for propane furnace, so we'll see what's needed with a new system.

I know in the past I'd heard heat pumps were not really recommended north of around North Carolina. We're mid-atlantic, and we're getting hammered by cold right now. Is a new generation heat pump really the best way to go for this climate? We won't ever have natural gas piped in to this community, so always propane as backup.

Thanks again.


 o
RE: new build hvac advice

Lots of negatives in the past about heat pumps. No longer true though and in your case with propane fuel, today's high eff heat pumps is your only choice to leverage electric versus more expensive propane fuel.

What is your electric cost? What is current cost of propane? You have been following the propane shortage story along with what has happened with pricing?

I would want a dealer with demonstrated experience in zoning and purchase just one system to handle the heating and cooling of your home.

If this was my home, I would be looking at geothermal or a Carrier Greenspeed system.

IMO


 o
RE: new build hvac advice

Thanks again, tigerdunes. Geothermal is out of the budget. The builder's hvac guy uses Lennox, so I guess that's what we get. I'll certainly ask about any other options. We're looking at an addional $4500 from furnace to heat pump--does that sound about right?


 o
RE: new build hvac advice

You want both. HP and furnace and zoning controls to handle your zones...sounds like 3 zones...

Not sure if we are on same page...

IMO


 o
RE: new build hvac advice

Thanks again, tigerdunes. Geothermal is out of the budget. The builder's hvac guy uses Lennox, so I guess that's what we get. I'll certainly ask about any other options. We're looking at an addional $4500 from furnace to heat pump--does that sound about right?


 o
RE: new build hvac advice

Sorry, don't know why that posted twice.

Trying to get on the same page, tigerdunes. To sum up my understanding, we're looking for a heat pump with propane back up, so separate (smaller?) furnace, and AC that's in the heat pump. Correct? What are the main differences between the Lennox units and the Carrier that you recommend? Or, what should I look for in any unit that we go with?

Thanks again.


 o
RE: new build hvac advice

Sorry, don't know why that posted twice.

Trying to get on the same page, tigerdunes. To sum up my understanding, we're looking for a heat pump with propane back up, so separate (smaller?) furnace, and AC that's in the heat pump. Correct? What are the main differences between the Lennox units and the Carrier that you recommend? Or, what should I look for in any unit that we go with?

Thanks again.


 o
RE: new build hvac advice

"Thanks again, tigerdunes. Geothermal is out of the budget. The builder's hvac guy uses Lennox, so I guess that's what we get. I'll certainly ask about any other options. We're looking at an addional $4500 from furnace to heat pump--does that sound about right?"

I can not help on the pricing because you never provided the baseline Mdl numbers your dealer initially quoted you. Nor have you provided the Mdl numbers to cover the extra $4500.

Carrier has a low temp heat pump called GreenSpeed. Suggest you go their site and read up on it. It is relatively new but anecdotally a successful introduction. Pricing would be up to 50% higher than a conventional high end DF furnace/HP system.

As far as Lennox, I was talking about one correctly sized system with zoning controls.

IMO


 o
RE: new build hvac advice

Tigerdunes, still trying to get questions answered by builder. He's very much a Lennox guy. What are the negatives for Lennox? What problems have you encountered? Thanks again.


 o
RE: new build hvac advice

It's not so much negative about Lennox but I think Carrier and Trane along with sister companies are better especially with their HPs. But I won't quibble over the models of Lennox furnace and HP that I gave you in older post.

If you go with zoning control off one system, you need to qualify builder/dealer in this area of expertise. Zoning is not for the inexperienced.

IMO


 o
RE: new build hvac advice

Tigerdunes and all pros

Builder set on Lennox heat pump, model 13HPX. Online reviews are mixed, at best; warranty looks to be minimal. Your input needed re other Lennox models, sort of least of evils option. Again house is 3400 main level, 1400 basement, 2 zones.

Thanks


 o
RE: new build hvac advice

13HPX is low end cheap POJ HP made South of the Border. Your dealer is looking out for himself, certainly not you. XP 17 minimum depending on propane Mdl furnace. What furnace does dealer plan on using?

IMO


 o
RE: new build hvac advice

I don't know furnace model yet, some other Lennox I'd assume. Anything I should request?


 o
RE: new build hvac advice

Yes, tell dealer to hit the road and get another one involved who is halfway interested in looking out for you. This dealer/builder is certainly not.

Go back and look at my original list. That is your starting point. At the very minimum, I would want a two stage var speed 95%+ eff furnace model.

IMO


 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