Random problems that can cause a no-start can be a real PITA. They can ONLY be diagnosed while the problem is actually happening. In all likelihood, there is only one possible correlation to the initial service, and its a significant stretch to make that call. If the Idle Air Control motor is sticking, and nor opening wide enough for the cold start the engine could flood. That easily could result in the diagnosis for the spark plus, and you really cannot do them without the rest of the secondary ignition parts. All you can really do at this point is pick the car back up. What I do for my customers is make myself available so that the next time that it happens, IF they are close enough, I go to the car and begin the diagnostics right there where the car is. Hopefully even if I can't complete the routine, I can definitely narrow down the problem as much as possible. Question. When this is hard to start, do you begin to touch the throttle and try and help it fire up? An issue with the idle air control could be worked around by doing just that. As a tech, I first know to do this, and usually react naturally with that step and start the car, occasionally wondering if this is the actual vehicle problem that has caused the repair visit. That potentially could explain why it starts all the time for them, but don't jump to conclusions here. That's only one possibility among many. The tune up work as done, very likely was maintenance that had been overdue, but not the cause of the no-start. At the same time, there is no way to know if they weren't right on with the diagnosis at that exact moment, and cars doing what they do, the thing has simply developed another issue. Timing of the failure aside, there is more than a good chance, the shop has performed exactly the way they should have, and actually may have done nothing wrong.

As far as your ductwork, is it metal or fiberglass? You can't clean fiberglass. Trane and American standard are good units but for the extra price and the fact that you are looking to save money, it might be a great Idea to check with a Local NuTone, Tappan, or Westinghouse Dealer. These are Nordyne produts. You just might be able to get yourself a 16 seer Split heat pump with a Var speed blower motor on the indoor unit, and a 2 stage compressor on the outdoor heatpump. Since this system would qualify for the tax credit you would get $1500.00 off, or look at it like this. You would get free ductwork. All this for what you will most likely pay just for the Trane system. As far as warranty, Trane nor Carrier can touch the Nordyne products warranty If you go with the Nordyne you will get 10 years all parts and 10 year quality Pledge. If the compressor fails for any reason within 10 years, you don't just get a new compressor you get the entire outdoor unit along with labor allowance to replace it. Also the outdoor fan motor on the nordyne never has to be oiled. Trane just gives you a new compressor. Better warranty, more for your money, less maintenance. One more thing you don't need a seacoast kit for the Nordyne product. www.nutonehvac.com check out that website and you can see pics of the units.

marzhere have no idea what Equinox is and would never recommend Goodman unless it was a case of budget consideration. obviously, you are grossly oversized with current furnace. I like the Lennox quote better with their modulating furnace. what stat was quoted? one thing though with the Lennox G71 is I don't believe it modulates up and down as demand changes. They may have worked this perculiarity out. ask dealer about this. don't think your load calc would be reliable. however, living area below grade usually calls for only small amount of heating and cooling. you would want a damper at the very least to help control the supply line airflow to this zone. Insist on a written load calc on software letterhead and review very carefully. you will need some type of air filter cabinet. was one quoted? and I would recommend new and correctly sized refrigerant lineset especially since you are going down in size on AC by 1/2 ton. post evap coil mdl number quoted. IMO

Good for you for doing the math. Let me throw a few issues into your calculations either for you or others that might be reading: 1. Depending on your climate and other factors, such as hot water use, the cost to heat your house is a significant portion of your bill but not the entire gas bill. Be sure you try to isolate the heating portion of the bill. 2. Your gas bill may include a "Delivery and services" charge that is constant, regardless of the amount of gas you use. If that's the case, remove that from your calculation. 3. Although there is some fluctuation now, the trend in energy prices will be up over the life of the furnace. 4. Take into account financing costs and opportunity costs. The money that you are talking about may have better payback if it was used to insulate or seal the duct work, for example. 5. In your case, the insulation in the attic will reduce your total gas bill and the break even will be lower than the $1200 that you estimate. Bottom line is that it usually doesn't make sense to go from 92% to 95% unless you can capture the tax credits. There can be a comfort benefit with multi-stage furnaces and variable speed blowers.