27 Nov How your heating system works
Being enveloped in warm, comfortable air can be an amazing feeling – especially on cold winter nights in Nashville, TN.
Conversely, suffering through a cold night because your heating system isn’t working properly can be very unpleasant. You may also notice your heating system just isn’t very efficient – which could be a sign of a problem or just mean it’s time for an upgrade. Here, we’ll tell you more about your heating system and how it works – just the basics, so you can understand what’s going on to create the warmth and comfort you crave.
Types of heating systems
There are several types of heating systems and it is important to know what type you have and how it works. Here are the basics.
Water is the ideal heat-transport vehicle. A small pipe filled with hot water carries as much heat as a large air-filled duct, and it fits far more easily between studs and joists. In most houses that use hot-water systems, the pipe carries water at 120 to 180 F to baseboard convectors that consist of a piece of copper tube running through a row of sheet metal fins. This sets up a convective heating loop as air is pulled in at the base and flows out the unit’s top. Newer radiant-heat systems use plastic tubing routed in a serpentine pattern. Usually this is installed under wood-frame floors, or it is encased in concrete.
A forced-air heating system is simple and versatile. By connecting a humidifier, air cleaner or evaporator cooling coil to the duct system, a homeowner can completely control the indoor air’s temperature, humidity and cleanliness. Air in these systems moves at about 700 ft per minute through the house in rectangular ducts, typically made from galvanized 30-gauge sheet steel. Some systems use round ducts connected to the main rectangular trunk, while other houses have flexible, round insulated ducts connected to an insulated trunk. In all cases, the joints in the duct system need to be meticulously sealed to prevent air leaks and energy loss.
About 7 percent of U.S. homes heat with oil, collectively consuming about 7 billion gal of fuel a year. Modern burners atomize the oil by pumping it at about 100 psi to a tiny brass or steel nozzle that turns it into a spinning, cone-shaped spray pattern consisting of about 55 billion droplets. The spray is ignited by a 20,000-volt arc produced by a pair of burner electrodes. The result: a clean-burning flame of 2200 to 2600 F.
A small but growing number of the nation’s homes have condensing boilers or furnaces–both more than 90 percent efficient. In these appliances, flue gas condenses in a secondary heat exchanger, releasing usable energy. The flue gas and condensate are routed to the outdoors via plastic pipe. The equipment gains further efficiency by using unheated outdoor air for combustion, rather than conditioned indoor air.
Shutting it Down
While keeping your heat on and running is very important, so is knowing how to shut it down in case of emergency or repair. You may suspect a gas leak or you may need to check out the system, and if so, you very likely will want to shut the system down. Here’s what to look for.
- Boiler Shutoff Valve: Stops water flow to the boiler and to valves or other devices downstream. (It is the first of several valves and devices on the boiler’s feed line.)
- Burner Emergency Switch: Cuts power to a gas- or oil-burner circuit.
- Main Shutoff Valve: Controls gas flow from the meter to the building for maintenance or emergencies. The valve is turned with an adjustable wrench.
- Propane Tank Service Valve: Controls gas flow from the tank to the building for maintenance or emergencies.
- Circuit Breaker: Provides a means to automatically or manually cut power to heating-equipment circuits.
Problems? Questions? Call Mid-State Air Conditioning, Heating & Plumbing in Nashville, TN.
We’re here to help keep your heating system running strong. We have technicians on call 7 days a week in Middle Tennessee for emergency repairs, or we can schedule a routine tune up as part of ongoing preventive maintenance services. Contact Mid-State in Nashville, TN to learn more about our repair and maintenance services.