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Need Help on choosing NEW HVAC system!!!

6 years ago

I need some help and advice as I'm a new homeowner with very little knowledge about furnaces. Our furnace has been turning off in the last month but goes back on when we reset it. The unit is approximately 20 years old and the sellers gave a year home warranty as part of our sales contract. We called the warranty company (bad customer service btw), and they sent out their technician who diagnosed a bad circuit board. The warranty company has authorized to replace the furnace with a comparable unit but we would have to pay for non covered items and gave us these 2 choices:

Non-covered breakdown with Total: sheet metal mods $250.00 + flue pipe mods $150.00 + gas shut off valve mods $150.00 + gas pipe mods $125.00 + electrical mods $125.00 + disposal $60.00 = $860.00

SPECS ON NEW UNIT: Carrier 80% efficiency, 70k BTU, 3 ton Furnace: PG8MAA036070

You also have an option to take a cash out in lieu of your repair or replacement.

Cashout Option: $1500

We are also thinking of replacing the AC at the same time since it also 20+ years old. Here are details of what we currently have and 2 quotes from other contractors:

Home: 1450 square foot one level ranch with crawlspace, located in Chicagoland area

Current Furnace: Carrier 58RAV115-16, 80% AFUE, 115,000 BTU

Current AC: Carrier 3 Ton (don't have model #)

Quote#1:

Bryant Preferred series 2 stage gas valve w/ Ecm motor: $4900.00

  • 95% two stage gas valve, ecm speed blower, 80,000 btu furnace.
  • Remove old unit and discard. Run 2 in PVC exhaust pipe to vent of the house.
  • Connect electrical, The unit has a ten year parts warranty with a lifetime heat exchanger. 1 year labor warranty.

Bryant Preferred series 13 seer 3 Ton Air Conditioner: $3700.00

  • Indoor matching coil Installation to Include: new Bryant 14 seer ac condenser new matching coil new condensation drain to existing new electrical whip new condenser pad with UV protection new insulation on refrigerant lines from new to existing.
  • 10 year warranty on parts 5 year labor. Must service ac system every year.

TOTAL $8,600.00

Quote #2:

Carrier Comfort Series Single Stage Chimney Vented Furnaces with ECM Blower Motor

  • Model#: 58SC0A090E17-14
  • 80 % AFUE 88,000 Input Btu’s 71,000 Output Btu’s
  • 20 Year Warranty on Heat Exchanger

Carrier Performance Puron Air Conditioners

  • Model # 24ACB336
  • 3 ton 13 SEER 36,000 btu 10 year warranty on compressor 20 ft 3/8 and 3/4 Copper
  • Includes new custom made sheet metal return transition
  • Uncased 3 Ton Puron Evaporator Coil installed in crawlspace Outside Whip & Disconnect

TOTAL SUM: $5, 175.00

OR, For the higher efficiency furnace model from same contractor

2–Carrier Comfort Series Single Stage PVC Furnaces with ECM Blower Motor

  • Model #59SC5B060E14-12
  • 96.5% AFUE 60,000 Input btu’s 58,000Output btu’s
  • Lifetime Warranty on Heat Exchanger
  • NOTE: THIS FURNACE IS ELIGIBLE FOR GAS CO. REBATE OF $200.00

TOTAL SUM: $6160.00 (Furnace & AC)

This price includes: Complete installation of the equipment according to manufacturer’s specifications Complete removal of old equipment & debris from premises Reconnect electrical, water, drain, gas pipe & copper Complete start up and test of equipment operation 5 Year Warranty on Labor (To obtain 10 Year Warranty on Labor customer must purchase a yearly Maintenance Agreement) 10 Year Warranty on Parts


Any advice on making a decision would be greatly appreciated!

Comments (24)

  • 6 years ago

    80% efficiency on the gas furnace is pretty pathetic by modern standards. You should be able to get something that works better. While you are at it, have the HVAC contractor calculate the correct size of the unit. Both under- and oversized units are bad news.


    We have had a central AC solution with a cooling coil in the furnace's duct work. I find that it is not very effective overall. Personally, I wouldn't recommend going this route, if you are changing out things anyway.


    We now have several point-of-use minisplit units, and they work so much better. It's like night and day. Also, our minisplit can operate as a heat pump. That's often a better heating solution, until it gets really cold outside. But then, we live in a very temperate climate. So, that makes sense for us, but might not be as useful in your case.

  • 6 years ago

    You current furnace is about twice the size it needs to be and 20 years old. If you plan to live in this house at least 5 years, then it does not make sense to invest any more money into it. The Home Warranty company wants to replace it with the cheapest furnace and will likely do a poor installation. My advice is to take the $1500 and hire an experienced HVAC company to do the installation.


    The Bryant Preferred and Carrier Performance series of equipment are good options. For your climate a 95%+ efficiency furnace would be best. I think 60K BTU should be sufficient, 2.5 or 3 tons of cooling. I would be great if you can find a HVAC contractor who will do a load calculation. I think spending the extra money on a 2-stage or variable speed furnace is worth it especially if it qualifies for a utility rebate.

    Be careful of labor warranties which force you to sign up for an annual maintenance. It might not be worth it. The parts warranty from the manufacturer does not require a maintenance contract.

  • 6 years ago

    From the service sticker on the furnace, it looked like the circuit board was replaced 5 years ago, would it still be safe to replace again to get more life out it?

  • 6 years ago
    last modified: 6 years ago

    t bird, we played that game for a few years with 2 old furnaces and AC units. 1 year pay to fix this one, the next year fix the other one. About 4 years ago we got all new Trane variable systems...furnaces and AC units. I can't tell you how much more comfortable the house is! No hot spots, no cold spots. Not hearing the constant heating which was either all on, or all off. This one just hums on the back ground and I barely notice it. Very much worth the $$$$. I would take the money and get a new system...many HVAC companies offer payment plans.

  • 6 years ago
    last modified: 6 years ago

    Thanks for the input, I was thinking about going that route with the cashout and using our local HVAC in our same town. And yes, I was told the current unit is too big for our house. We do plan on stay here for 10+ years or do.

    I asked about the 2 stage and why he didn’t recommend it as an option and was told that we really don’t need it because of the size our house and being on one level. He also said many clients found the 2 stage to be louder and asked to switch it out in many homes in our area.

    Our local HVAC did not push any maintenance warranty and infomed us of all the rebates for the energy efficient model. He also offers 12 month 0% financing through his own without using a bank.

  • 6 years ago
    last modified: 6 years ago

    Did you ask about variable speed...it's not the same as 2 stage? Ours is incredibly quiet.

  • 6 years ago

    Both carrier models have variable speed blowers which he states makes it quieter.

    What is everyone’s experience with adding a humidifier since it’s very dry in winter?

  • 6 years ago

    It may be that the 80% was recommended because the furnace is in a crawlspace that might get below freezing (thus freezing a condensate line).

    M, it might be that your AC wasn't functioning to your satisfaction because it was poorly chosen, the equipment was mismatched, it was poorly installed, or had operating problems. A huge number of homes have gas forced air furnaces with a "coil in the airpath" setup for AC and it works just fine.


  • 6 years ago

    Replacing the board isn't a problem. It may now be aftermarket and have a 5 year lifespan.

  • 6 years ago
    last modified: 6 years ago

    Elmer, the furnace is not in the crawl space, it’s on the main floor in a closed in room/closet with a vented door between the bathroom and kitchens area.

    I was told if we went with the 96 efficiency, we could put a solid door in front of the unit because it will now be vented out through the roof instead of chimney, which is an added way to make it quieter.

    I‘lol admit our unit now makes the biggest SWOOSH noise when it fires up and it can be quite annoying.

  • 6 years ago

    Both carrier models have variable speed blowers which he states makes it quieter.


    This can make it difficult (impossible?) to use third-party thermostats such as Nest. This might be a non-issue for you. But it is something you should inquire about, if you plan on using one of the many third-party thermostats that are integrated with home-automation systems.


    Other than that, yes, variable speed blowers are nice.

  • 6 years ago

    They told me that they recommend the Ecobee instead of Nest because it has a 4 wire system instead of 5 wire which may not be compatible with many home systems. Other than that, they said they could install the Ecobee with the Carrier 96 option.

  • 6 years ago

    If they are talking about 4 wire vs 5 wire, then that probably means that they are not sure whether you have a common wire that runs all the way to the thermostat. There are all sorts of work-arounds for not having a common wire, and some smart thermostats work better than others in this configuration. But at the end of the end, it's something you should just fix.


    In many situations, there are enough wires in the wall, and you simply have to connect the common wire at the furnace. In some older houses, that might not be the case. But this is literally the easiest new wiring job to do. Installing low-voltage wire is generally pretty straight-forward. Ask an electrician to run a new thermostat wire and forget all the headache of dealing with thermostats that almost but not quite work; or worrying about a furnace that burns out after a year, because it isn't quite compatible with the "power stealing" scheme that the thermostat implements.

    t bird thanked M
  • 6 years ago

    You need a load calculation done, not a rule of thumb guess.


    The home warranty company wants out for the least money possible, so it’s not worth having them do the work, IMHO, take the cash.


    Replace both heating and a/c, but beware that the ducts may be incorrectly oversized and need adjusting/replacing, an additional cost.

  • 6 years ago

    I asked my husband, who was there when the contractor came out, and the second quote company said Carrier has a satellite software program to do the load calculation by typing in your address. That’s how he came up with the 2 Carrier models he quoted us.

  • 6 years ago
    last modified: 6 years ago

    That's baloney. Carrier may have a program to do load calculations but to be done correctly, load calculations require lots of data inputs specific to the house- construction factors and details, square footage and floor layout, R value of wall, ceiling and subfloor insulation, the number type and size of windows, and lots of other stuff.

  • 6 years ago

    t bird, ask for the load calculation, and then ask them to show you the type of insulation they input, the type of windows, the size of overhang, the wall materials, etc...


    What they say they did is crap. They simply took the square footage and wagged (wild ass guess) the materials based upon property age, if that. A just slightly small system is infinitely preferable to a too large system.

  • 6 years ago
    last modified: 6 years ago

    I completely agree with Fudd (and would have used a stronger word than "baloney.") Any company that won't do a "Manual J" load calculation on your home should NOT be hired to install your new system! Here is a good explanation of why doing a load calculation is so important: https://www.pvhvac.com/blog/why-the-manual-j-load-calculation-is-key-to-hvac-design

    And a 96% efficient furnace is definitely preferable to the 80% offering (in which 20% of the gas you purchase to make it run -- is wasted.) In this day and age, please go with the furnace that only wastes 4% of the gas you purchase. Even your gas utility bill with thank you, with lower monthly costs to run your new furnace (than if you'd bought the 80% efficient version).

  • 6 years ago

    A 96% furnace is not a universal solution, but, if the OP is in Michigan, the climate is a good choice for a 96% unit. It’s a waste of money in most of the South.

  • 6 years ago

    The OP is in Chicago area. A 95%+ eff furnace is justified. I would take the settlement, find a reputable dealer and purchase a mid range 95% eff single stage furnace with a mid range 15-16 SEER AC, both properly sized. I would think a 60 KBTU furnace with high eff blower mtr would be adequate. Get a filter cabinet. Obviously your existing furnace is grossly oversized. Please no low end builder grade system.


    IMO



  • 6 years ago

    Thank you, Opinions really help since I never had to make a purchase this before and reading everything online can be overwhelming!

    I will be taking the cash and getting the higher efficiency model and having another contractor come for an estimate this week.

  • 6 years ago

    Tigerdunes has given you good guidance for the target specification for a new system. Let's see what is specified in the next quote. HVAC contractors who don't do load calculations are apprehensive about specifying a furnace half the size of the existing one. Be prepared for different furnace and AC sizes.

  • 6 years ago
    last modified: 6 years ago

    I would heed Elmer J Fudd's caution regarding freezing condensate lines. If they freeze, they will fill up with condensate and trip the furnace's safety float switch - NO HEAT! If the furnace condensate can't drain into a conditioned space drain, I wouldn't get a condensing furnace.

    The comment above about thermostats not working with variable speed blowers is incorrect.

    t bird thanked sktn77a