A few points: I think, as others have pointed out, that bringing your home up to the basic standard will not earn you a premium, but having electric baseboard heat will be used against you. What can help you is if you do a high-efficiency furnace and A/C. Since you own the home, you may qualify for utility rebates on an energy star rated A/C unit. People are hip to the fact that an older home isn't as energy efficient -- so they appreciate an efficient furnace and A/C. What's also attractive to a new buyer is that the system is NEW and if they can get a transferable warranty on it. (I have a 10 year transferable parts and labor warranty on my HVAC and that's a selling point) Also, check on state tax credits for all of the work you are doing because it's in a historic district. I get a 20% state tax credit. A side note: if it's in a historic district don't mess it up doing things that you THINK are historic. I can't tell you how many house flippers have ruined homes in my neighborhood doing exactly that (replacing or moving doors or windows, for example). Don't guess - find out. Or they do things to "fix up" an old house that are going to have to immediately be undone by anyone buying the house such as vinyl siding. Or they do things like fix up the interior without doing mechanicals, so the new owner is going to have to open the walls that were just all skim coated and painted to add insulation, outlets and plumbing.

First off, I think you must ask dealer what upgrades you need to make to your attic where dealer will guarantee against freeze ups. That's if you are serious about placing a high eff condensing furnace in attic. Then get pricing from an insulation contractor and/or dealer if he provides that type of work. Weigh the cost of the upgrade and decide if it's worth it. I think quote #1 is ridiculously high. Good comprehensive list though for scope of work. Compare to the other quotes for apples to apples. On quote #2, I want R8 insulation up and down. I don't believe you require a 90 KBTU furnace for upstairs area. I would want to see the load calc to support that size. Drop down to 70 K model. I assume Infinity controllers for both systems. How many returns on each floor? I would want two returns on each floor, properly sized and strategically located. Filter cabinets on both systems? I think a 3 ton condenser for upstairs is oversized and would suggest going down to a 2 1/2 ton Sgl stage high eff model. Don't like that condenser on the Trane quote. I would like to see evap coil model numbers. What about filter cabinets? What model thermostats? Is this rental property? Who will remove old radiators and old pipes and make necessary repairs including flooring? These are just some general observations. IMO This post was edited by tigerdunes on Tue, Aug 20, 13 at 13:02

Tigerdunes brought up demand defrost versus timed defrost. For the past 18 years, I have dealt with my Lennox defrost scheme. The only times I heard it go into defrost mode were when the unit was first running in heat mode. The unit would switch over from heat to defrost, the defrost cycle would complete and everything would turn off. I never heard it run a defrost cycle when it was not first heating. I rarely heard it go into defrost. I never heard it defrost on a fixed cycle such as every 90 minutes. Am I to understand that a Carrier will just go into defrost mode every X minutes whether it needs it or not and is not in a heating cycle; just turn on and defrost itself? I found this information in the Carrier 25HNB6 heat pump installation instructions: AUTO defrost adjusts the defrost interval time based on the last defrost time as follows: When defrost time When defrost time 3-5 minutes, the next defrost interval=90 minutes. When defrost time 5-7 minutes, the next defrost interval=60 minutes. When defrost time >7 minutes, the next defrost interval=30 minutes. The control board accumulates compressor run time. As the accumulated run time approaches the selected defrost interval time, the control board monitors the coil temperature sensor for a defrost demand. If a defrost demand exists, a defrost cycle will be initiated at the end of the selected time interval. A defrost demand exists when the coil temperature is at or below 32_F (0_C) for 4 minutes during the interval. From that description, if the time interval elapses and the coil is not at 32 degress, then no defrost will take place. That, to me, sounds like a form of demand defrost. Is Baldloonie saying that the coil could be at 32 degrees or less without frost and, therefore, a defrost cycle would be unnecessary? What kind of ambient sensor detects presence or absence of frost? Neohioheatpump asked, "When your old A/C would run, was it producing water?" It was producing water and I saw it dripping from the condensate drain. One weekend I went out of town and came back to find water on the floor around the return box that the fan coil sits on. I opened up the access and found the interior insulation of that box soaked. Turns out the condensate line was plugged. Took awhile for that to dry out. On the other hand, this past summer I did not see water dripping from the condensate drain. The drain line was not plugged and the drip pan seemed dry. I thought it was because I had dried out the air so much with the two dehumidifiers that there wasn't enough remaining for the A/C to remove. Cooling was normal. Running the fan on manual started with the installation of the Lennox and an associated Honeywell Electronic Air Cleaner. The house suddenly became dusty and I blamed the EAC for not doing its job. The Honeywell zone representative came to my house, sized up the situation, and told me to run the fan on manual so that the dust would remain suspended in the air and available to be captured by the EAC. I did that and it was of no help for the dust situation but it did help reduce the temperature differential between the first and second floors during cooling so I kept doing it as a matter of routine. Thus, I cannot say that not running the fan reduced the humidity. Though I complained about humidity, the heat pump contractor never told me that I was humidifying the house by running the fan (on orders from the Honeywell rep). I will continue to run at least one dehumidifier in the completely below grade basement during the summer because I want that area to be warm and dry to avoid mold and mildew. I've been in the basements of other houses in the area that don't use dehumidifiers and they stink. Mike Home said, "You stated in an earlier post that you run the fan in the summer because the upper floor is 2-3 degrees hotter than the lower floor. I think adding the attic insulation will help this." I agree that adding attic insulation could help. But, having a Dutch Colonial house with a barn-like roof that is covered in dark shingles on the east and west sides causes a lot of heat gain through the second floor walls. I'm not keen on opening the walls to determine the amount of insulation or add to it. Changing to a light-colored roof would make the house look out of character with the neighborhood. There are newer shingles that reject heat gain that I will investigate. Mike Home also said, "You could also zone the first and second floors, but this is expensive and probably not feasible with your current duct work." There is but one main feed duct and it runs through the basement. There is no way to segregate the room feeds in this scheme without doing each one individually. I'll leave that expense to the next owner.

Hydro air systems are not very common. I have no experience with them and they are rarely discussed on this forum. How much do you spend annually on fuel oil for heating and domestic hot water? I imagine it is a lot of money. Have you considered abandoning the hydro air and installing a heat pump in it's place? The installation costs should be comparable in either case, but I would think you would save money on heating costs and you could get a matched system with a 10 year parts warranty. It think a 2 ton AC for 1500 sq feet on the third floor seems a bit undersized. Was the old AC able to keep up on a hot day? SEER ratings are for a matched system of condenser, coil, and air handler. If go with the First Company hydro air handler and the Carrier condenser, you will have a mismatched system. That means the SEER rating is unknown. If you spend the extra money on the 2-stage condenser it will be more efficient but you won't know by how much. The 2-stage condenser is great for controlling humidity. But be aware that in a 2-ton condenser, the low and high stages are about 1.3 and 2 tons. It is not until you get to the 3 and 4 ton sizes that the differences are more noticeable. It is something to think about.