Is this a drastic solution? What would you do..?

Discussion in 'HVAC Heating & Cooling' started by lithnights, May 25, 2009.

  1. lithnights

    lithnights New Member

    Messages:
    143
    Location:
    PA
    I have a two story house in PA, forced hot air and A/C supplied by gas.

    Due to numerous renovations and rerouting of supply ducts and returns, I have a lot of inefficiencies in the system. The 1st floor is fine but the ducts to the 2nd floor now go through a a myriad of twists, turns, then up a wall then another turn, then up into the attic, then across the attic then down into the rooms via each ceiling.

    One bedroom no longer has a return. One bedroom has no ductwork at all due to it being an addition. Two bedrooms rely on space heaters during the winter since they don't get enough forced hot air. The 2nd floor is actually cooler during the winter, not what I'd expect with hot air rising.

    Also, I have a lot of ductwork rerouted throughout the unfinished basement, a basement I want to finish but will lose much headspace due to the multiple pieces of ductwork.

    THUS... it has been suggested that I install a heat pump in the attic that would supply heat and cooling to the 2nd floor. The existing furnace and compressor would supply the 1st floor. This would allow me to get rid of the maze of rerouted ductwork and returns and return efficiencies. It would also give me a two zone system.

    QUESTIONS:

    Is this a good solution?
    Is it worth the money that it would cost?
    What other options would you suggest?


    Thanks in advance!
  2. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    27,267
    Location:
    Cave Creek, Arizona
    heat pump

    It is about the least expensive way to get both heating and cooling to the area. However, heat pumps are not always the most efficient way to do it, depending on where you live and the expected low temperatures in the wintertime.
  3. jimbo

    jimbo Plumber

    Messages:
    8,997
    Location:
    San Diego
    In your climate, you would have to have backup electric heat for the winter months.

    What about a boiler in the basement and hot water heat for the second floor?
  4. lithnights

    lithnights New Member

    Messages:
    143
    Location:
    PA
    So when you say least expensive way do you mean the actual install of it? Thus, actually running it is not the most cost effective (I assume b/c I need to use electric to run it instead of gas), but install is not expensive?

    I am in the Philadelphia area where the average low (I just looked it up!) for the coldest three months are.. January 25 degrees, Feb 27, Dec 30. Of course we get a night or two where it dips into the teens or single digits but that is few and far between.
    Last edited: May 26, 2009
  5. lithnights

    lithnights New Member

    Messages:
    143
    Location:
    PA
    Can you explain why one would need backup electric heat and how I'd have to go about doing that? Do you mean a separate system as a backup or just using electric space heaters as needed?

    As far as the idea of a boiler in the basement and hot water heat for the 2nd floor, are you saying hot water heat in lieu of a heat pump? If so, what do I do for cooling the 2nd floor?
  6. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    22,325
    Location:
    New England
    An air source heat pump becomes inefficient when the air temp gets around 40-degrees or so. Below that, most need supplemental heat, and that usually comes from (optional) electric resistance heating units in the air handler. Also note that the air outlet temperature of a heat pump in heat mode is often fairly cool, nowhere near as hot as from a typical furnace. It takes careful positioning and sizing of the ducts so that the air flow doesn't feel like a cool breeze (fine in the summer when you need cooling, not so great in the winter when you need heat). Auxilliary heat is like a big electric heater...it adds heat when the heat pump can no longer extract enough from the cold outside air.

    Depending on your electrical costs, it can be quite expensive to provide heat on those cold days.

    With a boiler, you'd have several choices. You could put in baseboard heaters, or you could revamp the duct system and do a hydro-air system. Basically, run the hot water up to a properly sized radiator in the air handler or ductwork then blow that hot air to the ducts. You could place that part in the attic or somewhere closer to the destination. That same air handler could hold the a-coil for an a/c unit. Maybe all in a closet upstairs, and tap into the ductwork going from the attic for each room. If you run the air handler in the attic, you'd want to run an antifreeze solution in the boiler. A good boiler can run in the mid-90% efficiency and could be a good source to replace your existing WH with an indirect when your existing one dies. then, your WH costs would go down, since you'd be using mid- 90% efficiency burner verses one probably in the 50-60% range, and get faster recovery.
    Last edited: May 26, 2009
  7. lithnights

    lithnights New Member

    Messages:
    143
    Location:
    PA
    The more I read these replies, the less I think I want to use a heat pump. So if I decide a heat pump is too inefficient, but I want to utilize the existing good ductwork upstairs, yet still want to eliminate the ductwork config problems (between basement and upstairs) and still get heat and cooling to the 2nd floor, what are my options?

    Do I just use a 2nd boiler in the attic to supply the heat, then run the refrig lines to the attic and hook into the existing compressor/condesor, to supply the cool? Basically mimick the setup I have in the basement?

    If so, are the install costs much higher for this type of config? I assume running a gasline to the attic is not too easy.

    I don't really have a closet or other area to put the stuff so it would have to be in the attic.

    Also, by putting the setup in an uninsulated attic area, don't I sort of lose a bit of efficiency since the unit that is trying to heat or cool air is located in an environment that could be as low as 40 degrees in the winter (when trying to heat) and as high as 105 in the summer (when trying to cool).

    I'm trying not to get too confused here... bear with me. ;)
  8. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    22,325
    Location:
    New England
    FOr the a/c, you'd need a second outdoor compressor unit...you can't tap off the existing one...just doesn't work that way.

    You could also just put in a second furnace which probably would be cheaper than hydro-air. Radiators, if you go that way work, but can make placement of furniture more difficult. Hydro-air is about the same as a hot-air furnace, you're just replacing the heat medium. If you were willing to tear more up, you could do radiant floor heat - this would be the most expensive, though - very comfortable.

    Yet another option would be a split unit compressor unit. These can have multiple room heating/cooling units from one outside unit with individual room outlets (look sort of like a window a/c unit, but only maybe 3-4" thick). You can mount them anywhere on a wall, and get individual room a/c or heat. It would make individual room zoning very simple and built-in.

    Depends on what you want to do. If there's any way to maybe take part of a closet and run a more direct duct run, you might be able to balance and heat/cool with what you have.
  9. jimbo

    jimbo Plumber

    Messages:
    8,997
    Location:
    San Diego

    At some point....as the temp falls into the 30's , heat pumps lose their effectiveness, and stop heating altogether. That is when you have to have backup electric heat. Also, heat pumps put out a "gentle" heat. So when it is quite cold, you usually use 2nd stage electric heat to give you an initial boost.

    If you put in a boiler, you could use a multizone minisplit A/C for cooling.

    Now, all this stuff adds up to $$$$ so I would recommend getting some input from a contractor in your local area who is intimately familiar with the building construction and climates in your area, as well as utility rates since we are talking gas, oil,electric, etc.
  10. lithnights

    lithnights New Member

    Messages:
    143
    Location:
    PA
    Agree. The plan is to talk to a couple contractors and get their ideas. I just wanted to run the ideas by you all first since this forum is so great. I spoke to a plumber/HVAC guy already (sort of a friend of a friend) and he suggested the heat pump idea. He failed to mention much of the stuff that you guys mention, thus the reason I want to get as many opinions as possible.

    I'll get with some contractors and post an update when I get some suggestions from them.

    Thanks all!!
Similar Threads: drastic solution
Forum Title Date
HVAC Heating & Cooling what will be the best solution for heating and cooling? Mar 13, 2013
HVAC Heating & Cooling WIFI thermostat - inexpensive solution for remote control Apr 3, 2012
HVAC Heating & Cooling baseboard solution Nov 29, 2010

Share This Page