Great question. I think you may be confused on some things, so I am going to lay out some detailed info. First some background. Adding a gas furnace sounds like a given. Be sure to have your ductwork evaluated and make any changes to size or do any sealing of any leaky ducts. That is "step one" and with a minimal investment will get you heat in colder months, and also the possibility of "fan only" mode in warmer months to at least assist in circulating the air. This would be your most affordable option right now. The furnace would be in the basement. With your preferences for having the system on/off per your schedule, please add a programable thermostat. If you are into tech, look at the ecobee wi fi stat that you can operate from your phone or any web connection. This gives not only the ability to use your phone as a remote control for your system (why get out of bed if you get chilly in the middle of the night...just grab your phone and adjust), you can also be on your way home and adjust the temperature to be as you want it when you arrive home. If you would never use these features, then a standard programmable stat would allow a 7 day schedule to have the pre-set temperatures you wish to be programmed to occur automatically. Now, to add cooling to the home is a second step. You very well could do step one first, and do step 2 later if budget dictates this. To add cooling to an older home such as yours, a couple of things will need to be addressed. First, is your ductwork set up for enough return air for cooling? If not, then things like undercutting the bottom of the doors by 1/2 to and inch can be done to increase air circulation. If your current heat system is forced air then your home is most likely already configured properly for adding air conditioning. The second and more expensive question is do you have enough electrical power available for running AC? Depending on your electrical system, and how much renovations have been done on your home, you may need to upgrade your panel. You should have this evaluated if you are doing renovations, even if you decide to add the AC later, or want to be able to add it later. This would be a good selling feature even if you yourself don't ever add the AC. Then the third consideration on adding cooling is should you do straight AC for the outdoor unit, or an outdoor unit that is a heat pump. A standard direct expansion air to air heat pump is no different than straight AC in how it cools. (I am not discussing ground source heat pump systems, only basic DX, or direct expansion systems that use refrigerant. A ground source system would cost 3-4 times as much as a DX system, and is very extensive requiring wells or a water loop in a pond or well.) Based on cost of the equipment alone, a heat pump will be only slightly more costly than AC-- likely around $800 more would be a good estimate. What is the difference? An AC only condensing unit with the compressor is the outdoor part of the system. It will be hooked up via pressurized"freon" lines (although it is now called R410A refrigerant, not technically freon which is also known as R-22) to a evaporator coil that sits on top of the furnace in your basement. The fan from your furnace blows air from your home across the evaporator coil with the cold freon circulating in its tubes, and the heat from your home warms the freon, the freon circulates back outside in its piping system (the line set), and the fan out side blow the heat into the outside atmosphere. Then the compressor starts the process over. This is basically how AC works. So to add in AC you will need to add a coil on the furnace, the line sets between the indoor furnace and coil and the outdoor unit, and add the outdoor condensing unit. A heat pump is basically a AC condensing unit that has a reversing valve to switch the direction of the refrigerant flow. In cooling mode, it cools exactly the same way as the AC system. When the system is operating in HP mode, that is for heating the home. It is actually warming the refrigerant from the heat in the outside air and then the refrigerant flows to your home, and the coil and fan on the furnace are transferring the heat into your home's inside atmosphere. Remember the refrigerant is compressed, so it is pressurized and really cold, so 45 degree outside air really offers a good amount of heat to be transferred to the system. The advantage of a HP is that the amount of heat you get out for the amount of KW used is efficient. So that is the "big deal" But this is only important if your electric rates are very low compared to your natural gas rates, OR if you cannot do a gas furnace and your only other heat option would be electric heat. If you compare HP energy use to other all electric heat -either electric baseboard heat, or a heat strip in an air handler (sometimes called an electric furnace), then the HP may be the better buy. If you will primarily heat with natural gas, and have a mild climate (as you do), then it will most likely not be the best use of your money. Additionally, a mechanically simper AC only system would be preferred over the more complex piping and valves on a HP would require. So, I suggest checking out the duct work and adding in gas furnace. Get a good programmable stat. At the time of your remodel add in the electric to add in AC. Put in the AC if you would use it. Probably not worth the extra money to get the heat pump. Hope this has helped you with this. Here is a link that might be useful: Ecobee Home Model Smart SI

Just about the only thing that makes that happen is a very good and recent sale in the "neighborhood" of a house comparable to the one being appraised. Sometimes you'll have a buyer come in with cash (as from an inheritance or divorce settlement) who doesn't bother to get an appraisal. That sale can set a new high---although it is usually used as a fourth comparable since that doesn't represent the "typical" buyer. Strictly defined, a "neighborhood" is the either in the same subdivision or within one mile of the subject. Ideally the sale should have occurred within the previous six months. However, in rapidly changing market conditions some lenders ask for comps within three months. There are all kinds of exceptions to this guidline; for example, when you are in a subdivision that covers several miles and the only comps are within the s/d but beyond a mile. And a comp in the same s/d is better even if it is a mile or two away than a house just outside the s/d boundaries that is only a half-mile away. Things like s/d amenities that would attach to the subject but not the comp "outside the gates" so to speak, even if those gates are only metaphorical. When you have semi-rural properties or areas with no subdivisions it is permissible to go further away and farther back in time for comparable sales. It's very possible that someone bought a house a few miles from you that was in some way very like your house---and bought it within a few months of your own purchase. It's all about group behavior and not individual actions... you look at trends in sales and what other people have bought recently in the same area, try to find sales that match your subject best. When you have no subdivision, or you're in a rural area or dealing with unique properties, often the most difficult task is to identify the most important feature of a home---the number of bedrooms? the tennis court? the five-car garage? the finished basement media room? That's why Realtors are such wonderful resources for appraisers---if they will use their knowledge. They know what is selling houses in their area. Sometimes it is a school district---I've seen people pay $300K for a two-two in a highly desirable elementary school district. That's what makes the business interesting, there is something different with every assignment.

Boomer, you've tolerated what most would consider a hijack of your thread with good humor. There will be more to sift through, for relevant stuff, but learning will happen. There are a lot of dedicated posters in this site and it is a remarkably good site for little nonsense and good judgement in staying between the lines and with little flaming and insults. There are other sites for boilers and hydronic heat, however, if you really need to get into the nitty gritty. I suggest two places that I found very useful. The HVAC and boiler areas within the DIY area at terrylove.com are good. For example, right now there is a recently-active thread there about a monoflow system. That is type of system that shunts part of the water flow in a loop through radiators in sub loops using special "monoflow Ts" I doubt any significant number of systems based on that elegant principle have been installed for 50 years. It enables you to have single pipe circulation and install valves on individual radiators (thermostatic or not). Messing with the pump rate or other parameters might cause huge problems for the unwary or careless. If I had one and felt the need for some modification, I'd plan on hiring someone that knows what they are doing or spending a few hours learning about how it works. For the curious, looking at how monoflow systems work might be fun and I greatly appreciate the genius of the person that came up with the idea to begin with and the one that applied it to hydronic heat. Another site as good or better iis "the wall" at heating help.com. It is a well run site with lots of knowledgeable posters https://forum.heatinghelp.com. Right now there is a thread over there about steam vs. hydronic heat in a new build. That argument will never, never end even though the answer to me is clear.. terrylove.com the wall

Re: mike­_home I see a previous post by you has been deleted or taken down. Please don’t be ‘P.C’; there was nothing wrong or hostile about your post. We’re all ‘Long Distance’ friends here. Your question was fair and I’d like to answer it. I hope the reason for it no longer appearing is that you have answered it for yourself. So… “mike­_home Fsq4cw, You said: the average cost to run a 5-ton Waterfurnace Series 7 in all but the most brutal conditions would probably be ~51¢/hr. Can you show how you calculate this operating cost?” Sure Mike, I’d be glad to help. OP says he lives in Boston Mass. So from, ‘Ground Source Heat Pumps’, ‘Appendix 1 – Ground Temperatures’ (Kavanaugh & Rafferty 1997), ground water temperature in Boston is 50˚F. Makes sense to me, I’m in Montreal Canada and our GWT is ~46˚F. I think it’s actually a little colder but these guys literally wrote the book on this subject. This GWT is easily found on the web for any North American city. Next, if you download the specs for the Waterfurnace Series 7 HP and ‘Drill Down’ through the specs (there’s a lot of them), on page 38 you will find the specs for the 5-ton HP (060). OP’s contractor says a 3-ton Mitsubishi air source HP would do most of the job, so why not for argument’s sake say a 5-ton would also do most of the job too. Water furnace Series 7 (060) Ground temperature in Boston is 50˚F. So let’s say after running for a long, long time the EWT (Entering Water Temperature) returning from the ground is really cold, say, 30˚F, 2-degrees below freezing (no problem, fluids contains glycol and should easily be able to go down into the lower 20’s˚ F). The performance data (page 38) on the ‘060’, a 5-ton HP on ‘Part Load’ 50%, these things like long run times and will scroll down once the set point is met. So EWT 30˚F, 6.3 GPM flow rate from the boreholes, 850-cfm from the blower, LAT (Leaving Air Temperature) from the HP to the main plenum would be 98.6˚F, Power kW (i.e. TOTAL HEAT PUMP POWER) 2.17kW. OP pays 23.6¢/kW x 2.17kW = ~51.21¢/hr. The only thing that matters is the heat loss of the envelope, outdoor temperature can go down to -60˚F, as long as the ground temperature is stable, nothing changes for the heat pump, COP remains constant. Minor changes in ground temperatures near the surface generally lag by at least 1-season, unlike the air temperature that can change hour to hour. Below about 12-feet there is much less change. Below 200-feet the ground temperature actually starts to rise, boreholes can be 450-feet deep for residential. Hope that helps, SR