Central Ac

[jross]

We are deciding to install central air and get rid of the window units. Our local contractor says he can install the most efficient system available for around $8000. We have hydroponic heating so that includes ductwork and electrical work. How much in value would this add to our little 1250 ft sq, house if we were to sell it? Keep in mind we are in New Jersey with terrible humidity, on 40 acres, and open space in NJ is at premium prices which our tax bill reflects. Funding it is not a problem.

[agmantoo]

Are you stating that you have in floor Hydronic heat now? If so, what is the source of the heat? I would not just install a central AC system if I were installing new. For just a little money extra you could have a complete heatpump. Based on the prices of the various sources of heat you may find the high efficiency heatpump more affordable to operate in the future and at the same time have a full back up heating system. A geothermal heatpump would be my choice provided I had an existing source for the water.

[RosewoodfarmVA]

I second the heatpump as it only costs a few hundred more for the unit and you'll then have 2 options when heating costs vary so much in a season.

[GREENCOUNTYPETE]

look into a split system a lot less money no duct work we have them in our church and they do a great job you still have a outsdie unit like a central ac but then have a fairly centraly located evaps in boxes mounted on the wall this is like the part that would mount in the duct work abouve a furnace and make the air cold but it is usualy 2 of them mounted say in the main living area or at the top of the stairs in the between the bedrooms and one in the masster bed room they mount at the top of a wall near the celing and cool the hot air they have a small blower in them and cool a lot of air but need no ducts a system like this should be at least half as much as a fully installed system with ducts and like you siad your house insn't that big

we have 4 that cool our 100 year old church with 40 foot ceilings

you need the high preasure lin the low preasure line and a drip tube all the same things that would run to a unit mounted in a furnace these can offten be run easily thru walls where you could never get a duct besides your not trying to push cold air your moving coolant and the hot air comes to the unit thru normal convection

[cfabe]

Your house does sound like a good candidate for one of the new mini-split systems with one compressor outside and refrigerant lines running to a small air handler in each area. I think you could get a good system like this for much less than $8000 with much less disturbance to the house. Running ductwork is going to mean a lot of drywall work and that's messy.

Remember that there is a tax credit available for central air systems this year and next year I believe.

[jross]

Originally Posted by cfabe

Your house does sound like a good candidate for one of the new mini-split systems with one compressor outside and refrigerant lines running to a small air handler in each area. I think you could get a good system like this for much less than $8000 with much less disturbance to the house. Running ductwork is going to mean a lot of drywall work and that's messy.

Remember that there is a tax credit available for central air systems this year and next year I believe.

I have investigated mini splits and that is what I told the contractor. They stated a mini split system of two units, one for two zones and one for three zones would actually ending up costing more than a conventional system even though installation was easier and faster. He is working up an estimate for each system. Me being suspicious by nature am thinking they have conventional units they want to get rid of. The system they are presenting has the air handler and all the ducting in the attic which only means one hole in each ceiling and the return under the air handler in the central hallway. Plus he is doing electrical work which I could do, but he would be responsible for all the work if there is problem in the future.

[tyusclan]

I would not put mini-splits in a home. They are very expensive for what you get. They are fine for limited applications such a server room, but they are impractical for homes IMO.

I also would NOT let him put the air handler in the attic. The coils need to be cleaned at least once a year and it's a major nightmare to do any service to the unit when it's in the attic. You can install the air handler in a closet, and you still would only have to go through the ceiling once, and run the supply duct in the attic.

I also don't recommend heat pumps that far north. I know they're putting them in now, but I just don't think it's a good idea. They're going to stay in defrost A LOT when the weather is that cold, and when they go in defrost your heat strips come on. You lose your efficiency when that happens.

[cfabe]

I think installing a heat pump instead of a standard central air is a good idea even in the cold areas of the country, just not as a sole heat source. Heat pumps can also be installed on a gas forced air furnace like is normally used in the north rather than on an air handler with heat strips. Then you install a thermostat with an outside temp sensor and the system will use the heat pump to heat when temps are mild, and use gas when temps fall. Best of both worlds. If I ever get around to installing central air it's what I'm going to do.

[Joshie]

I don't think a heat pump would do the job for high humidity area. I would look into other options. Have you gotten estimates from several contractors? Personally, I'd want to live with central air, not without it. I would do this for my own comfort, not for resale value.

[tyusclan]

Originally Posted by Joshie

I don't think a heat pump would do the job for high humidity area. I would look into other options. Have you gotten estimates from several contractors? Personally, I'd want to live with central air, not without it. I would do this for my own comfort, not for resale value.

You can't get any worse humidity than where I live, and heat pumps do great here. A heat pump is simply an air conditioner in cooling mode. It reverses in heat, pulls heat out of the outside air and puts it in the house. When the ambient temp drops too low the condensing coils freeze up, and the unit reverses, goes into defrost, and the heat strips (or gas furnace as cfabe pointed out) comes on to heat the house until the coils defrost. It then reverses back and starts the cycle over.

[mtman]

Originally Posted by agmantoo

Are you stating that you have in floor Hydronic heat now? If so, what is the source of the heat? I would not just install a central AC system if I were installing new. For just a little money extra you could have a complete heatpump. Based on the prices of the various sources of heat you may find the high efficiency heatpump more affordable to operate in the future and at the same time have a full back up heating system. A geothermal heatpump would be my choice provided I had an existing source for the water.

heatpump is not a good idea in nj it gets to cold there

[agmantoo]

mtman, as cfabe stated above, until it gets real cold the heat from the heatpump portion of the central conditioning would be the cheaper heat. Once the temps drop and stay down they can switch to the hydronic system already installed. The difference between the AC only that is being discussed and a complete heatpump is minimal.

[artificer]

Split systems not economical: For new construction, they don't make sense. If you don't have to do much ducting, they don't make sense. If you have a long house with no attic or basement, ducting is going to cost a lot. The split system may make more sense. Its a case of get the costs, and see which is better/cheaper.

Heat pump and humidity: A heat pump is an AC system that can work in reverse. So... why will an AC system not work in high humidity? Thats where they have to be used when you can't use evaprative cooling. Heat pump function only makes it more versatile.

Redundant Heating: You already have hydronic heating. Since a heat pump only adds a couple hundred dollars, it might make sense to get it. Yes, when it gets very cold you can't use it. Up until that point, however, you get cheaper heat. Normally you don't have heat pumps in cold areas, but if you're already spending the money, a little bit more gets more options. Yet another option is to tie the heat pump into the hydronic system. When you call for heat, it acts like a boiler. What is the hydronic heated with? If electric (probably not) then the heat pump makes the most sense. Propane/NG needs to priced out to see what give the cheapest heat.

Cost of a split system: Take a look at this site for some prices. Rough guess for AC would be $2,000 for the 19,100BTU unit. $450 per room. So base price for 5 rooms would be $4,250. That gives you $3,750 for installation. If the quote comes in for a lot more, I would find someone that speciallizes in split systems to give a quote as well.

hydroponic heating: how does this work? Is this more than the standard hydronic heating? Hydronic plants with heated water? Solar heated plant tanks?

I guess it comes down to what the quotes are, and how extensive the modifications to the home need to be. I would suggest getting another quote anyway, just so you have a comparison.

Michael