Anyone with knowledge of furnaces?

is the new furnace high efficiency or standard (80% efficient is standard, 90-95% + is high).  Are you also adding cooling?

i don't know much about removing the oil system, but the furnace alone would be between $1100-$2k depending on efficiency and size. 

good idea getting multiple quotes.  However, remember that the quotes will likely not be apples to apples unless you have a detailed outline of what you want done.  The lowest cost contractor may not be the one to go with. 

Look very, very hard at Geothermal.

The new variable-speed units are unbelievably efficient. (41 EER and 5.8 COP!!!) Yes, the initial cost is going to be even more than switching to gas.   Payback is likely under 5 years, depending on the size of your house.

My total energy costs for my 3,500 sqft house for the past 3 years has been less than $1800/year.  There are about 3 months a year when my electric bill is less than $100.   I have no gas bill.  The new units are about 30% more efficient than mine!!

I'm never going back to "direct conversion" of fossil fuels for heat!

Depends on your *yard* ... of all things.  On a small lot, they will bring in a drilling machine and drill into your yard... 3 or 4 wells of about 150 feet deep. (unless you have a BIG house... more wells) and there will be a shallow trench between the wells and then back to the house.     On a large lot, they will dig a trench a couple hundred feet long (it  doesn't have to be straight, it can "bend" around your yard) and bury some pipes in it.   Our 4-ton system required a trench 250 feet long, 6 feet wide and 6 feet deep.  Yes, it's going to mess up your yard.  Ours was new construction so it wasn't an issue.

From inside the house, a new furnace drops in place of your old furnace.  To get the best efficiency, you also install a new water heater (or storage tank) next to your old water heater.  In the winter you take unlimited showers!!

There will also be a small "flow center" that circulates water between the wells and your furnace.

If you currently have central air, your outside compressor unit will go away.   If you don't have central air, you will gain it with geothermal!  In the summer, instead of pumping heat from the ground into your house, the system does the opposite.

stay away from heating oil.  Geothermal is sort of a waste of money, and if you enjoyed the heat you got from your previous system, a heat pump may not make you feel too warm and toasty at times.

My BIL has a large farmhouse that had 2 ancient oil furnaces that could no longer be repaired, and went with a propane system instead.  He got a Buderus system, slightly larger than the size of a suitcase mounted on the wall in the basement, instead of the dual oil systems the size of a small car.  He cut his yearly fuel bills from $5000/year down to $2000, so the savings for him were pretty significant.  Just my .02 to throw in there.

Have you checked with the local gas companies and your state/town about rebates for installing a more efficient heating system?  Typically there are lots of refunds to be had when doing this type of installation.  Whomever you are getting your quotes from should 100% know about this too.  It could be a couple hundred bucks between the heater, changeover, etc.  Also, the least expensive way to cut the bill (besides not use the heat) in an older house with forced air is to make sure your insulation is up to snuff (attic specifically as it's the easiest to replace/add to) around the house, ductwork insulation is in good shape, doors/windows are tight, programmable thermostats are always nice so you never have to remember to set it.  Whenever you're looking at insulation and those types of things there are always energy rebates associated with them. 

Radiant/hydronic heating is defintely cheaper in the long run as water can transer a lot more heat than air, but switching over to that system is insanely expensive and I would only recommend if you were already tearing up the floors or something for another project.

We got a quote for replacing our oil furnace at the end of the summer.  The cost was around 8k.  This was for an 86% efficient boiler, adding a pump to create another zone and removing the oil tank.  Our oil tank is located in the basement so the cost for removal is significantly less.  I haven't read the thread, so I do not know if anyone covered the "what if the oil tank is leaking".  I assume that if your UG tank is taking on water it probably has a leak and that remediation gets expensive, very expensive fast.  We had to deal with this for our community center this year and the cost was around $30k and it was a very small leak. 

HTH

edit to add we have baseboard heat and not forced air. 

Oil-fired hot water baseboard heat here near Philly.

It was about 6k I think; it was part of a larger project that included Solar-Thermal hot water.

Buderus boiler, with an outdoor sensor, so it adjusts hot water temp based on outside temperatures.  Cut my oil use IN HALF.

And my old boiler actually ran pretty well.  The Thermal Efficiency number isn't the whole story; all that does is show how well your burning fuel.  How it transfers heat into the water is the other part of the equation.

I would go to gas, but it isn't available on my street.  So it's oil or propane.  And electric is $$$ in this part of the country, in the winter. 

Looked into Geo as well, but at the time, it wasn't going to be cost-effective

This summer I repalced a 1950s gas boiler for a HE unit based on the recomendation of a home energy audit. Insulation in the attic is the next project but that is another story.

Get an energy audit, my $350 audit took 4 hrs to do and with rebates from the utility companies only cost me $50. It gave me great ideas to help my home.  The boiler I had was gas and ran at 50-60 % efficiency and the plumbing looked like a upside down octopus. I wanted efficiency and a clean install.  The company I went with charged me $10K to remove the old, replace with a HE unit and clean up a lot of the plumbing and install digital thermostats.  So far house feels more consistant on temp.  I am very happy with the end result and see it as a good investment into the home and great selling point should the future force a move.  I anticipate a 9 yr return on this investment and shorter once I finish the insulation and other energy leaks.

Good luck. 

It does not require the wells to reach water.  It's a 4 or 6" bore hole in which black polyethylene pipes will be inserted and then grouted.   wells only need to be separated by 10'.   It is possible to do one DEEP hole but several shallow holes are slightly more efficient.

They do this in Manhattan, btw.  pull right up on the sidewalk with the rig and drill down '1000 feet(or whatever)  Lot size can be challenging but not a problem... if that makes sense.

Geothermal is rarely a "waste of money" as another poster stated.

Total installed cost for my system was $16,000, compared to $8,000 for ASHP.   I'm saving about $1400 a year over the cost of ASHP, and about $2500 a year over propane.   NG is not available in my area. 

Payback in my case is just over 5 years.  for a system with a 5 year warranty and an estimated 20 year life.... I'll take it.

Your case may be different... I would find out.

Couldn't agree more, just moved from an old convent that had geo thermal, 3500 sq ft, not insulated very well (1940 house). Intial cost of install of GT was 20000, back in the mid 1990's. Hydro bill was never more than 200 in winter (-40c Canada) averaged about 60 in the summer. GT did heat, cool and hot water. Kept the house at 70F.

Now have forced air a new house and hydro bill is about the same, ALL YEAR round! When my furnace kacks will definitely be looking into GT, keep in mind though a new GT furnace is almost 10000 but they last about 15-20 yrs.

I switched over from Oil to Propane about 15 years ago.  I had the local farmer bring his truck over and pumped out the fuel oil.  They used it in the tractor, they got free oil and I got a empty tank.  I demoed the old heater and two of use hauled the tank out of the basement.  I ran the new gas line and built the stand to set the new furnace on to reach the duct work.  My wifes uncle had his contracotrs card and we bought the furnace wholesale.  I did not have my own slack tube so he set the regulator and did the leak check for me.

Overall I spent about $500 on it. 

Ask friends and neighbors for contractor recomendations.  Get 3-4 quotes and go with who seems the most reliable.  The installation quality is more important than the brand or price.  This is the most expensive time of the year to get a furnace installed.  Everyone has plenty of work...

Geothermal can make sense in some locations, mainly cold climates with no natural gas availble.  It would take a lot longer than 5 years to payback the cost in my area.

The super duper "instantaneous" water heaters that come with a rebate really dont save that much gas over an old standing pilot model.  Maybe five bucks a month in an average house.  They have a lot more expensive things that can/will break over time.  The only reason I would consider one of the instantaneous ones is for safety.  They do have more safetys to prevent a problem from dumping fumes (carbon monoxide) into the home.

I cant see the vent location being that big of a deal.  If part of the cost was relocating the vents I would see what the other contractors think.  Hard to give a good opinion without seeing it, but I wouldnt think the "worst" location you could put the vents would cause that much problem.

I'd love to know what you base this generalization on, as it's completely inaccurate.  Ground source heat pumps have been found to be one of the most energy efficient HVAC systems and the payback typically within 5-10 years.