No problem and I appreciate you being ok with me bumping into your exchange here- I am following this with alot of interest. Just quickly, on my issue, the installer came back out. At first he said this was normal as shared earlier and had to be told (from a non-expert) that this was not normal at all. It seems that he made some type of wiring adjustments (unknown since my wife cant follow any of this when she was watching and asking) and then adjusted settings within the setup of the Edge Thermidisstat. We are currently running oil heated-water baseboard as the backup and then the Performance series HP system (EER 12.5, SEER 15.5 and HSPF 9) cant find the AHRI# handy. Temps have been consistently at between 28 and 34 degrees here in Viginia for the last 5-7 days. We are having to manually switch from HP to the oil heat system for right now since I dont want this installer messing with anyting else to connect a relay that allows both to be working from the one thermostat. I will do that later (hence reason for following this discussion closely) I am tracking kW useage off the meter. Here's what I am seeing: Set the HP Edge at 68 degrees and it holds house temp steady wihtout having to use AUX at all. Set the oil heat-boiler at 66 setpoint(manual) It seems that only infrequently will the boiler kick on to augment the HP (running simul right now) Energy useage has been between 3.12 and 3.77 kW per hour across last 5 days (taken in 24 hr periods). VaPOwer is at about .06 cents per kW right now I think, so I'm looking at what 744 hours per month at avg 3.44 kW (.20 cents) per hour= $153.00/month. This is for a brick ranch, 1820 sq ft house

woke up and my wife told me she smelled a strong oil smell and shut off the furnace. i'm so groggy and out of it in the morning i have no idea. she told me to "check it out", whatever that means. I go look at it. It's a furnace allright. half a tank of oil. i call emergency service and tell them and they tell me 6 hours. i noted some soot on the outside, but these things are so filthy that who knows when it got there and how long it's been there. my theory was it sooted up because that's what happened last time we had oil smell (turned out the cause then was the wrong size nozzle installed). It's been very cold here lately due to an arctic snow blast. single digits a few nites. teens in the days. well, today when the oil smell happened, it was a balmy 31 when we woke up. turning the furnace off all day waiting for the guy to show wasn't a big deal. strategically placed electric heaters and a roaring fire in the fireplace ensured that it never really got cold. he took the guts of the furnace apart and it all looked good. no significant soot or anything. he suggested that it could be a cracked heat exchanger but didn't check it per se. after he got the furnace back together he said there was one more thing he wanted to check. he started examining the run of pipe to the exhaust stack and discovered a 2-3 inch gap. i recalled a dead bird i found in the sealed off furnace room a month or so ago. couldn't figure out how it got in there and threw it in the trash. well i guess we know now. so he squished the pipes back together and secured with a sheet metal screw. no more gap. i have no idea if this fixed the problem. it may make sense. i've felt like $#!+ all day with a sore throat.. my wife complains that it's worse when she goes upstairs. i have a few windows open, downstairs and up. With a huge roaring fire trying to suck everything out through the chimney. oh and i ran out and bought a second CO detector, just in case the one i have is broken. i just hope it fixes the problem. if it doesn't, do i just keep calling techs back until i find someone who can figure it out? how do you check a heat exchanger? (all he said was it was hard to see into my unit 'cos it's so small) is there a reason why we haven't noticed "oil smell" until the first normal temperature day following an unprecedented coldspell? i'm a couple hours from easton, pa, how much does our forum moderator charge? ;)

There are two balance points, temperature and economic. A lot of these calculations depend first on an accurate Man J calculation which is rare and the software necessary to produce each of these reports. Of course you must have accurate rates and efficiency. Most dealers don't know how to do this or have the software and time to produce these calculations. But it is available. Frankly I think good dealers should be able to provide this at a reasonable cost with the amount deducted from the cost of an installed system. All these manufacterer residential experts on staff at the respective distributors can do these reports. This is both a knowledge and time issue. Of course you and I know that the COP is reduced as the temp drops and these intersecting lines will vary from home to home. But you have to go on what you do know. I would never be concerned about the economic balance point when oil and propane are the backups. You just run the heat pump as low as it can go and/or comfort issues come into play. Nat gas though is where knowing the economic balance point could prove to be handy if you want to be operationally efficient as possible with fuel choice. Not my strong suit and I don't have the time to waste on this without being reimbursed. And that's always an issue in the HVAC business. Keep in mind most of the people who contribute to this forum do have an outside life. Sometimes these posters forget that. Everyone wanting your knowledge for nothing. It is generally accepted that COP begins to really take a hit around freezing. Of course lower for the GreenSpeeds and higher for low end junk that unfortunately there is plenty of supply. "The COP that you used in your fuel cost comparison - 2.47 - would suggest an outside temp in the 40s or 50s I would have thought. A COP around 30 degrees anbient temp would seemingly be down in the 1-1.25 range for many regular HPs." As I said I used 2.75 COP in this thread which may be conservative but I believe is fair. And you are correct that this COP is based on mid 40s outside temp. But as I have said previously, you must go on what you know. And I always preface these results to be used as a guide only. I would not agree with you that at freezing COP would be in the range of 1-1.25 for a high quality HP system. TD

You'll probably require a new outdoor unit (heat pump) and indoor coil whichever brand you go with since your indoor coil is likely incompatible with anything newer today. The furnace should be fine, as long as it is in good shape and can support (provide adequate airflow for) what you pair it with. The model number on the furnace will be inside the access panels. Amana's ASZ14 heat pump with matching coil would be a nice option with a lower upfront cost, but Trane (American Standard), Carrier (Bryant), Lennox, and Rheem (Ruud) are worth looking into as well. Call local reputable firms to get a couple estimates based on your needs, and post back if you can. I would also suggest having your ductwork looked at. Inadequate ductwork will raise utility costs and decrease the performance of any system.