Where’s the A/C?

[Editor’s Note: The following letters are in response to John R. Hall’s Feb. 19 editorial, “Will Consumers Turn to Hydronics Because of High Fuel Costs?” which dealt with the cost of hydronic systems vs. forced air systems.]

I read Mr. Hall’s column in the Feb. 19 News with great interest. The biggest problem with your proposed residential comparison is that you ignore air conditioning. Since over 80% of new construction in the U.S. has central air conditioning, this must be included in the system cost comparisons. Since the cheapest way to add central air conditioning to a hydronic system is to add a forced-air system to it, hydronic can hardly be cost competitive to forced air for heating and cooling, in terms of first cost and life-cycle costs. I do believe that going to a hybrid system which circulates hot or cold water to multiple small fancoils located throughout a house or light commercial building could be cost effective if the necessary fancoils were developed. This system could really have an economic advantage with electrical utility deregulation since it would be much easier to incorporate thermal storage (ice or water).

Roy Crawford Honeywell International

Choose Fuel Type First

I read John Hall’s Feb. 19 editorial, and those are some good questions. I, too, would like to see which type of system would have the best payback. I would think from what I have read that hydronic systems have higher first cost but longer life expectancies. Therefore, if the right fuel is chosen, then payback of hydronic systems could be lowered.

Down here in North Carolina, a lot of fuel switching is going on now because of the high cost of fossil fuels. Right now a 7-HSPF heat pump is the most economical way to heat a home, although this is not typical. Some folks don’t like heat pumps because they feel cold all the time. For people who don’t like heat pumps, fuel oil No. 2 is the cheapest and you can actually feel warm with 130°F supply temps.

Techs feel that the oil burners require more maintenance than gas or LP. I would stress that regardless of which equipment you install, yearly maintenance is a must. The first cost of oil-fired equipment can be as much as 10 to 15% higher than gas/LP. This cost differential, regardless if warm air or hydronic systems, can be paid back in less than 3 to 5 years.

The real first decision is which fuel to use in your area. U.S. DOE predicts the price increases for gas and LP to go beyond fuel oil increases. The secondary decision would be which type of system to purchase.

We tend to ask for the lowest first- cost system, forgetting yearly operational cost and maintenance. Pay me now or the utilities later. We preach to buy quality and efficiency, but we rarely practice what we preach.

Our forefathers decided one day that if we spend time and money on the initial installation, then the equipment would last much longer. They decided to cover bridges and protect them from the weather, therefore increasing life expectancy a great deal. This was a huge decision, because there was no Home Depot, nor were there any local, state or federal government help. They were farmers-craftsmen who decided to take the time and effort to do it right, forgoing the first cost.

When they build engineering projects today, they do an engineer’s cost analysis, based on first cost, salvage valve, life expectancy, and operational-maintenance cost. Do you build the bridge out of concrete or steel?

From the parameters given, a good contractor should be able to work up the pricing. I hope gas and oil don’t increase 25% per year.

Tim Laughlin, P.E. North Carolina Petroleum Marketers Association Raleigh, NC

A Few Choices Left Out

John R. Hall’s recent request to cost different heating systems and compare their operating expenses leaves open other questions. He left out air-to-air heat pumps and straight electric systems. We are a wholesale distributor that supports forced air, geothermal, and hydronic systems. All forced-air systems would have essentially the same costs for the duct systems. The cost of the heat source — oil, gas, heat pump, or geothermal — is the variance. What is the efficiency of the heat source? The gas system can vary from 78% to 96%, and the oil has similar ranges.

Air-to-air heat pumps and geothermal systems have a broad range of efficiency as well. The air-to-air heat pumps and geothermal systems have air conditioning as part of their systems and it is easy to add air conditioning to the forced-air gas and oil systems.

When referring to hydronic systems you would have to separate in-floor from baseboard, as there are some baseboard systems that are radiant. Both these systems are heating only and adding air conditioning would be a major increase in cost. You would also have to factor in the fuel type and efficiency of the boiler as well.

After you bring all the systems to the same level of efficiency and add air conditioning, you will probably find the following:

  • On initial installed cost, the forced- air systems, other than geothermal, would have the lowest cost with the order being gas, oil, air-to-air heat pump. Baseboard radiant is next, then geothermal and finally in-floor hydronic. Operating costs would vary with the cost of the utility and that also assumes that all three fuel types are available. Obviously, if the cost of delivered Btu were the same, operating costs would be almost the same. In-floor hydronic systems can offer slightly lower operating costs by their design, but not dramatically so. Utility costs will not allow the price of delivered Btu to be the same so your mileage may vary.

  • Other points of consideration are life expectancies and comfort. In-floor hydronic systems would last the longest with the boiler having a life expectancy of over 30 years. The baseboard radiant system would depend on abuse of the panels and the boiler having a similar life. The geothermal system would be about the same.

  • Geothermal systems do not experience the tortures of air-to-air heat pumps and, therefore, enjoy a long life. Forced-air gas and oil furnaces last about 18 years residentially and the air-to-air heat pump is around 13 to 15 years. The quality of the manufacturer has a great deal to do with life cycles as well as the installing and servicing contractor.

  • Comfort is dependent on the user. In-floor hydronic heating is the most comfortable without question. Base-board systems can do quite well also. The placement of ductwork for air con-ditioning with these systems does not mandate a compromise, as with forced-air systems so, theoretically, the cooling comfort should be greater as well.

  • All the forced-air systems, assuming no construction limitations, must have some compromise in register location. Typically, these systems will have either floor or low-sidewall locations or high-sidewall or ceiling registers. Low favors heating and high favors cooling. The gas and oil systems have high discharge air temperatures with geothermal not far behind. Air-to-air systems have the lowest air temperatures and varies with outdoor temperatures and mode of operation. Air-to-air pumps require more skill in register location and still may not be comfortable to older people.

  • Another point of consideration is ease of finding a good service contractor. This will vary by market. Forced air is more prevalent and as a result, hydronic contractors are harder to find.

  • Geothermal is part of our business as well. In Georgia, open-loop systems are not really allowed and loop contractors are few and those willing and able to provide service for loop problems even fewer. The refrigeration side of geothermal is not a problem, but the water side is something air-side contractors have difficulty with.

    • A small consideration for geothermal systems is the ease of free or low-cost domestic water heating with factory- installed desuperheaters.

  • Commercially, things can really change. In-floor hydronic may not be a big difference in a retail business but warehouse heating is another matter. Thermal inversion offered by in-floor hydronic, as opposed to conventional unit heaters, can create a big difference in operating costs — enough so to make a payback in a reasonable amount of time.

  • Residentially, it is not a simple answer. My real advice would be to find a contractor you like and trust and follow his advice. If he knows his business, he will know the best answer for your market. I have been in this business almost 30 years and a real truth is fancy products that may look good on paper are not worth a hoot if you can’t find a good company to service it.

    • John Ladd Commercial Hvac Sales Manager Apex Supply Company Lawrenceville, GA

    Publication date: 04/02/2001

    Study Heating and Cooling Model

    I work with many contractors who have managed to merge the “trades” of geothermal, forced air, and radiant heating (and occasional cooling). I might add that they’ve figured out how to offer and sell these hybrid systems in a very profitable manner!

    Yes, there are those from what some might call the “old school” who figure it’s “us-uns against you-uns” (to use a Southern expression). It obviously doesn’t have to be the wet heads against the tin knockers. This isn’t really “pushing the envelope.” It’s called “Find out what the customer wants and sell it to them” (at 30% to 40%-plus gross profit). Many successful contractors have been doing this for years.

    In regard to the “hypothetical models” as proposed in John Hall’s Feb. 19 editorial: Let’s look at a 2,000-sq-ft new home first. The first question to ask might be: “Are we wanting to compare life-cycle costs of different heating (and cooling) technologies or different heating sources?” It would be very easy to, say, take a heating-only model and compare forced-air heating with natural gas, propane, and fuel oil furnaces vs. radiant heating with any or all of these fuel types and a geothermal heat pump with forced air and/or radiant heating.

    I believe a more interesting application than a “heating only” model would be a Midwest environment with need for heating and cooling (say like maybe Kansas or Nebraska). You could assume a peak heating load of say 58,000 Btuh and a sensible cooling load of 41,000 Btuh or ask a contractor in this region for numbers from a similarly laid out home.

    The next “$64,000 question” would be what fuel costs to use. I’ve heard of natural gas going for $1.20 to $2-plus per ccf and propane going for anywhere from $1.50 to $2.60 per gallon. Fuel oil is not nearly as prominently used as the above or heat pumps of air source of geothermal varieties.

    I’ve heard from contractors and consumers from each area of the country with their twist on the “energy crisis” in their area. A pretty severe winter combined with skyrocketing fuel costs has created a phenomenal interest in geothermal heating and cooling. It only took a few $300 to $900 a month heating bills to get their fingers walking through the various Internet search engines to find us.

    Another statement Hall made was to “…then calculate costs to maintain the system…” Since he followed this sentence with comments about future utility cost increases, I assume he meant costs to operate the systems versus maintain them over the ensuing years. In truth, any complete “life-cycle” analysis should include projected maintenance and service costs. There are many varied opinions about the virtues of one technology or fuel source over another.

    Again, I believe a meaningful example would involve a home with both a heating and a cooling load. The 10,000-sq-ft retail store example will certainly involve a heating and a cooling load with lighting, people, and solar (window) load adding substan-tially to cooling requirements. Again, we could ask contractors or engineers to donate figures from a comparable commercial project and use the heat gain/loss figures, which they provide.

    I’m pretty confident that from a perspective of cost to operate, service, and maintain, The News will get feedback that rates the technologies as follows: geothermal, radiant, natural gas, propane, then fuel oil (from least costly to most). Again, advocates of certain technologies will probably sing the praises of their favorite and possibly site horror stories of their least favorite technology.

    With up-front costs to install being the highest for geothermal, the life cycle or “return on investment” analysis gets pretty interesting (and certainly subject to opinion). Using inflation figures of 25% per year for natural gas (propane) and fuel oil and 5% for water and electricity are as good as any. I haven’t seen any 10-year projections for these various fuels, but it would be easy to contact some utilities and get some projections and, hopefully, some sort of consensus.

    Chris Pamplin American GeoThermal DX Murfreesboro, TN

    The Wave of the Future

    Regardless of the fuel it is compared to, geothermal heating and cooling is the wave of the future. The reason, simply, is that it takes much less energy to move heat than to produce it. When combined with radiant heating, geothermal has a COP of 4 or greater. No fossil-fueled heating source can come close to that efficiency. Combine that advantage with cheaper air conditioning and hot water and it’s win, win, win. With higher fuel costs, the higher initial cost of geothermal is starting to look like a great investment.

    By the way, the price of water has little to do with heating systems. All the hydronic systems I am aware of are closed loop and consume very little water (unless they spring a leak).

    James K. Rogers, P.E. Energy Consultant Chelmsford, MA

    Publication date: 04/02/2001