Hydronic Heating

Boilers, Hydronic heat, Floor Radiation are new concepts to some people and old concepts to others. However the new technology with baseboard and floor radiant heat has changed tremendously from it's predecessor of years ago. Today you can have a floor radiation system that heats each room individually with the maximum energy efficiency. Imagine a heating system with no drafts, no cold feet, no noisy blower. Imagine a heating system where each room is exactly the temperature setting you desire with it's own thermostat control. Also think of the energy savings that can be achieved when each room that is not occupied can be reduced in temperature without affecting the other areas of your house. That's what a hot water radiant heating system can do for you.

DESCO will size a complete hot water baseboard and/or Floor Radiation system for you. Simply fill out our online sizing form and submit the information requested about your house. If you are building a new house or would like to renovate an existing house also send us a copy of the plans. The plans should include an elevated view, one direction either North, East, West Or South and the size of the windows. The drawing or plan does not need to be to scale as long as the dimensions are listed. To go to our online sizing form, Click Here. You can email plans to us at info@descoenergy.com or fax your plans to us at 717-846-3880.

Boilers

There are two basic types of boilers, those that produce steam and those that produce hot water.

Steam boilers are vapor or low pressure systems for residential applications. A vapor steam boiler produces steam at very low pressure measured in ounces of pressure and a low pressure steam boiler produces steam in pounds per square inch and usually operates at 2 to 8 pounds of pressure. There are one pipe and two pipe steam systems. Vapor systems are one pipe systems and low pressure steam systems are two pipe systems. Two pipe systems have steam traps at the radiators which Steam boilers and their systems are one of the most inefficient types of heating today resulting in significant heat losses due to the very nature of their design and operation. Although considered very comfortable steam heat can be noisy and is somewhat difficult to keep the heat in balance. This unbalanced effect results in hot spots and thermal losses through walls where the steam pipes travel. The best maintained steam system results in a 55% efficiency using an 80% efficient boiler. Remember the boiler is only one part of the system and the efficiency of the boiler relates only to the combustion efficiency. Other major factors play a significant role in the efficiency of a steam heating system and that includes the proper operation of steam traps if used, the insulation of the steam pipes, the location of the piping and radiators and the efficiency of the condensate returning to the boiler. There really is no such "Beast" as an efficient steam heating system. Our best advice is to remove the steam system and replace it with a more efficient hot water system. Sometimes the steam radiators are of sufficient size that a steam system can be converted to a hot water system using the existing steam radiators.  If you plan on keeping a steam system check the steam traps for proper operation, make certain bleed vents are working correctly and replace as required, have the boiler tuned up for maximum efficiency and make certain all steam pipes are properly insulated. Steam systems are very old and have been installed many years ago. Be extremely careful if you are performing any maintenance to the boiler and the steam pipes. Many of these systems were covered with asbestos insulation. Boilers and piping were wrapped in asbestos and asbestos is very dangerous to your lungs if it is inhaled. In fact asbestos that is inhaled stays in your lungs and has been responsible for many respiratory problems including cancer and death. Call in a professional to examine the insulation to determine if it is asbestos before you attempt to remove or disturb the insulation. Older hot water systems used asbestos insulation also. Asbestos insulation has a matted appearance and upon closer examination you will see the fibers of asbestos in the insulation. There are two methods of dealing with asbestos. The first method is to pay a specialty contractor to come in remove the asbestos. An asbestos abatement contractor is specially trained in removing or containing the asbestos using proper containment suits and ventilation. This can be a very expensive ordeal. Installing a protective covering over the insulation to prevent the asbestos fibers from entering the atmosphere and being inhaled is probably the least favorable method. In any event handling of asbestos should be left to a specialized trained professional asbestos abatement contractor who is properly educated and insured to handle removal or containment. If you were to hire a technician or moonlighter to remove asbestos from a boiler or piping who is not aware or properly trained and that person develops any lung or respiratory problems as a result, you could be held personally responsible. So if you have any question whatsoever that your boiler or piping has possible asbestos it is better to hire a trained contractor before proceeding any further.

Hot Water Systems

There are three basic types of hot water systems. The oldest is hot water heat using cast iron radiators as the heat source. Then there is the traditional baseboard radiation which is a copper tune with fins covered by a sheet metal shell. Baseboard heat has not changed much over the years. There are high output baseboard heat sections that also have two or more sets of copper tubing with aluminum fins that provide higher output. The third type of hot water heat is the newer in floor radiation heat that uses plastic tubing as the heat source. Before plastic tubing there was floor radiant heat that used steel pipe or copper tubing in the floor. Today's modern heating systems use a combination of baseboard and in floor radiant heat to provide the best heating system available. To learn more about in floor radiant heating Click Here to watch the video.

Boiler Types

The most important ingredient to any hot water heating system is the boiler which produces the hot water. Many years ago coal was the main source of heat for many homes throughout the northern parts of the United States. Built like an Army Tank these boilers were extremely thick and big. They used cast iron and had to be able to withstand the high temperatures of coal. Efficiency was never considered as coal was rather inexpensive and ventilation was the main consideration. If a boiler leaked or cracked the coal produced very high amounts of carbon monoxide and could quickly cause death if not attended to immediately. So coal furnaces had to be built like tanks. Coal was dirty and required manual labor to fire the boilers. As natural gas and fuel oil became more readily available these boilers were converted to use the newer fuels. By installing an oil or gas power burner the old dinosaur boilers were still kept intact to use natural gas and fuel oil. In fact many are still in use today. Operating at efficiencies of 50% or less these energy hogs consume high amounts of energy. Although some homeowners believed then and still believe today their boiler is efficient because a combustion test was performed. The combustion test read 70% or even as high as 80% efficiencies. What the homeowner doesn't realize is when that old coal converted beast isn't firing the boiler takes large amounts of heated air from the house on a continuous basis and funnels it up the chimney when the boiler is shut off. This effect is from the natural draft of the boiler. A boiler needs to have proper draft in order to ventilate and exhaust the byproducts of combustion. When the boiler isn't firing however that draft continues to exhaust warm conditioned air form the house. The tremendous continuous draft during the off cycles removes not only conditioned heated air but removes the heat form the heat exchanger and hot water in the boiler. When these losses are taken into consideration it quickly becomes apparent how the inefficiencies and losses add up and result in an overall heating efficiency of 50% or less. Today's newer boilers are much smaller and use less draft volume and as a result have a total operating efficiency of 80% or more. Also stack dampers can be used which stop the draft of the boiler in the off cycles. Today's boilers are rated as AFUE or Annual Fuel Utilization Efficiency which takes the total performance of the boiler both during firing and the losses of the off cycles into consideration for the rating, not just the firing rating.

Boilers come in different styles and configurations. The most common boiler is the standard cast iron boiler. Compared to their predecessors the cast iron boilers of today are miniaturized due to the increased efficiency requirements. No boiler or furnace can be manufactured today with less than a 78% AFUE.  There are also steel boilers which are very similar to the cast iron but use steel instead of cast iron. Cast iron is more durable and has better heat transfer than steel. The newest boilers are the new Ultra Wall Hung Trinity boilers. Using all the latest in technology and performance, the Trinity Wall Hung Boilers are the most energy efficient with 95% AFUE. Weighing in at only 80 pounds the Trinity boiler is mounted on a wall and takes up no floor space. At 95% efficiency and using PVC as venting the Trinity incorporates hot water reset among it's many features. Hot water reset changes the hot water temperature in accordance with the outside air temperature resulting in an additional 16% energy reduction.  The Trinity boilers also use modulation for firing which means the Trinity gas valve has a throttle similar to a car. Standard boilers use one or two stage firing and this is similar to operating your car at full throttle to maintain speed. When you reach the desired speed you would shut off your car to let it drift down to a lower speed and then restart the car again at full throttle to maintain speed again. Can you imagine how difficult it would be to maintain speed operating your car under these conditions? The Trinity boiler's technology is the same as adding a throttle to the car. The Trinity boiler is the same as 10 models of another manufacturer's cast iron boilers. The Trinity modulates the firing rate from 25% of the full capacity on up to the maximum output. The Trinity T150 boiler is the same as a 40k btu, 60k btu, 80k btu, 100k btu, 120k btu or even a 140k btu cast iron boiler. Unlike cast iron boilers, you can't oversize a Trinity boiler because the performance and output capacity of the boiler modulate to the heating requirements of the house resulting in longer on periods and extremely low off cycle losses. The Trinity saves space and energy and does not require expensive B venting or a chimney. A hot water domestic coil can also be added to the Trinity to provide domestic water. The Model is then a T150C. All instantaneous domestic hot water heater heaters have a limited output capacity. When using more than one hot water outlet such as 2 showers at a time or a shower as well as a washing machine, etc. all instantaneous domestic heaters have a tendency to spike. This spiking results in a discharge hot water temperature that will vary from 80 degrees to the limit setting of 115 or 120 degrees. To remedy this problem a regular hot water heater should be installed as a storage tank with a small recirculatory pump. The pump would then be piped from the domestic water heater to the hot water heater storage tank and to a return loop from all the hot water fixtures in the house. This set up then provides instant abundant efficient hot water at every fixture in the house and eliminates the spiking when two or more fixtures are in use at the same time. 

The Trinity has 2 models to choose from which is the T-150 and the T200. The T150 boiler has a capacity of 50k btus to 145k btus input at 95% efficiency. The T200 has a capacity of 75k to 200k btus. There is a new T200 series unit coming in the near future with a broader turn down range and even more technology.

Cast iron boilers are rated at an average of 80 to 86% efficiency. Cast iron boilers can come with standing pilot or electronic ignition for natural gas and propane applications. At DESCO we stock the New Yorker (Division of Burnham, Peerless and Utica boilers. To view the New Yorker Boiler specifications and installation information Click Here. To view the Peerless boilers and specifications, Click Here. To view the Utica boilers and specifications, Click Here. Cast iron boilers are less expensive than the Trinity Ultra Technology Wall Hung Boilers however when taken into consideration the requirement of a chimney and "B" Vent for the cast iron boilers, the Trinity installed actually costs the same or less than a cast iron boiler. To learn more about the Trinity boilers and to view the full specifications, Click Here.

Boiler Efficiencies and Hot Water Reset

An important note to remember on all boilers and their rated efficiencies is a standard baseboard heating system where the water temperature is set at 180 degrees, the boiler will never achieve more than 84% efficiency regardless of the AFUE rating. It is beneficial to add hot water reset to any hot water boiler. Hot water rest lowers and increases the hot water temperature on a set ration based on the outside temperature.  For example you don't need 180 degree water to heat your house when the outside air temperature is 50 degrees. But a boiler that maintains a constant temperature produces the same hot water regardless of the heating requirements on the house resulting in wasted energy and excess heat loss and boiler operation. By using hot water reset you could establish a schedule where the hot water temperature is 180 degrees at 0 degrees outside temperature and 90 degrees when the outside temperature is 60 degrees. So for each degree the outside temperature changes the hot water temperature changes 1.5 degrees. Hot water reset can be added to any boiler and will generally result in a 16% reduction in energy consumption. For a more detailed explanation and energy savings achieved through hot water reset Click Here.

On a standard efficiency boiler (80-86%) that is gas fired for residential applications we recommend a standard atmospheric type of burner. An atmospheric burner is a ribbon type of burner that a series in a ribbon pattern to allow the gas to burn using natural draft caused by the combustion process. The second method is a gun type burner which has one gas orifice and uses a draft fan to assist the combustion process. This type of burner is used on larger commercial and industrial boilers and old boilers that have been converted form coal to gas.

The basic natural draft cast iron boiler has a gas valve, electronic ignition, circulation pump, temperature controller and safety limits. Very simple to install and troubleshoot.

We do not recommend the use of propane unless the purchase price is less that $1.25 per gallon on a consistent basis. At $1.35 per gallon propane is more than the price of pure electric heat in most parts of the country. An oil fired boiler should be considered in lieu of propane. We stock oil fired boilers in efficiencies up to 86%.

How a hot water heating system is designed beyond the boiler is as important as the boiler itself both for energy savings and comfort. The main system should be piped as a primary and secondary loop. With primary and secondary looping the boiler's circulation pump simply circulates the water through the boiler. The secondary loop is the loop with one or more circulation pumps that provide heat to the zones. The more zones in a hot water system the better control and efficiency you will have. Rather than use zone valves we recommend using pumps. Using one pump and several zone valves results in inconsistent flow rates. Further zone valves have short life spans and do not provide the equal reliability of pumps. Today's technology has provided a wealth of opportunities to save energy as well as proved perfect temperature control. At DESCO we handle the complete line of TACO products including control boards, circulation pumps, zone valves, etc. For more information on Taco products please Click Here. For hydronic systems that incorporate both baseboard and in floor radiation heat where two different temperature requirements exist the TACO variable speed injection pumps can be used. Hot water reset can even be incorporated into the pumps and zone valves with the TACO technology.

In trying to understand what goes into making a hot water radiant heating system first learn the basics by watching this video, Click Here. For information about baseboard heat and a great source for basic information form Slant Fin, Click Here. Although a hydronic heating system may seem overwhelming at first, once you learn the basics, you can begin to envision what will be required to do a complete job. The boiler is only one part of many parts required. The boiler needs to have a water feed system and an expansion tack. The water feed valve maintains a constant static water pressure in the system based on the height above the boiler. The expansion tank absorbs the expansion caused by the water density increase due to heating. The expansion tank is sized by the capacity of the boiler and the amount of water calculated to be in the system. Without the expansion tank the system pressure would increase and the relief valve on the boiler would lift every time the boiler would fire. So to maintain constant system pressure an expansion tank is installed. Other components necessary are air scoops and air bleed offs. An air scoop is placed on the discharge of the boiler to remove and separate air that may be in the system and relive this to the atmosphere via an automatic air vent. If air is allowed to be in the system, this will create pockets where the water will not circulate resulting in little or no heat. Air vents should also be strategically located throughout the system at the highest points to provide air removal and at loops where the air cold be entrapped such as basement floor loops. There are also non automatic air vents which require the use of a wrench or screwdriver to manually open the vent and purge any air from the system. Manual air vents won't leak like automatic air vents but they also won't automatically purge the air either when there is an accumulation. In each loop that uses circulation pumps on each zone there also needs to be a flow check valve. The purpose of the flow check valve is to prevent convective circulation of the hot water when the pump isn't on. In older hot water systems many times circulation pumps were not used. The water circulated through the system just by the flow created by the temperature difference of the water or convective flow. So if a zone or system doesn't have a flow check valve then the water will continue to circulate causing overheating. Also in the event of a pump failure in the middle of winter, the flow check valve can be manually opened allowing the house to continue to heat until the pump can be serviced. To see all the components and a detailed description take a House Tour at Bell and Gossett, Click Here

For floor radiant heating systems the component materials are the plastic tubing usually called PEX tubing. Not all Pex tubing is the same and not all tubing has the same properties. At DESCO we stock and distribute Zurn tubing products with oxygen inhibitor. No matter where you purchase your tubing only use oxygen inhibited tubing which prevents oxygen accumulation in the water to attack the tubing causing tubing failure years form now. The last thing any homeowner wants is to have a tubing failure in a floor which will result in extensive damage to the house and a lot of money to replace the tubing. In the instance of tubing that is installed in concrete floors, this is the ultimate disaster which will necessitate abandonment of the system. Each tubing run should be made with 1/2" tubing and be no more than 300 feet in total length. Each loop will then return to a common header point next to the boiler and be piped into a manifold. In the case of areas where there is large glass exposure or high vaulted ceilings requiring more heat per square foot then the tubing should be double run. For the complete installation guide to installing radiant heat, Click Here. To watch the video on floor radiant installation systems, Click Here. At DESCO we will design your hydronic system complete with details of the tubing runs required when you make a commitment to purchase a boiler and associated components. To learn more about PEX tubing, manifolds, etc. please Click Here to go to Zurn's web site.

If you are building a new house, send us a copy of the plans and fill out our online sizing form at http://www.descoenergy.com for a complete sizing requirement. We do not provide a complete design until there has been a financial commitment to the purchase of a system.

Also one note to any new construction or additions. One of the biggest problems we find in new construction is houses that have concrete slabs only have insulation installed in the base of the slab. Remember it is just as important to have insulation installed on the edges of the slab as well. With no insulation on the edges of the slab the heat is allowed to transmit directly to the ground in contact with the slab and at a higher rate than under the slab. In over 80% of the plans we review there is no insulation on the edges of the slab. For whatever reason this important insulation is overlooked resulting in major heat loss. Make certain if you are building a new house or addition the contractor installs at least 2" of foam insulation on the edges of the slab.

A major side benefit to hydronic heating is for allergy sufferers. If you or a member of your household suffers from allergies then a hydronic heating system is perfect for you. There is a lot of attention given today on indoor air quality products such as electrostatic filters, hepa filters and whole house heat exchangers. These products are strictly for forced air systems and are marketed as remedies for allergy sufferers. Some products such as ultra violet lighting are useless and have no proven scientific benefit. The best way to combat allergies is to eliminate the movement of air in the house. Forced air systems are perfect breeding grounds for dust mites and other dust and pollen particles. Hydronic heat simply creates no breeding grounds and has the minimum air movement required. As a result homes that are heated with in floor radiation or baseboard heat have the lowest airborne particles and the least effect on allergy sufferers. So if your need is better indoor air quality, hydronic heat is the perfect choice.

DESCO will select and assist you in the selection of all components to put together a complete hydronic heating system including the design. For more information visit http://www.descoenergy.com