Click here to schedule
an appointment

When a furnace blows cold air, it’s usually at the worst possible time, like the chilliest spell of the year or the night of an important family gathering. Furnaces are remarkably reliable and usually only an require an annual tune-up by an HVAC professional and regular filter changes by the homeowner. Normally, they'll provide a decade or more of trouble-free service before furnace replacement is required. When a furnace blows cold air, there may be a simple explanation or it may be a sign that something more serious has gone awry. That's when you need a service call from an HVAC professional to sort it out. Here are some of the possibilities:

  • Nothing’s wrong. The answer we all like to hear. In fact, for the first moment of a furnace’s “on” cycle, the blower is normally flushing cold air out of the ducts. Warm air should follow quickly. If it doesn’t, schedule a service call with your local HVAC contractor.
  • Fan only operation. Check out the fan setting on the thermostat and make sure it’s set to “auto” and not to “on.” When the fan is in the “on” position the blower runs continuously, even when the furnace burner cycles off and only cold air is circulated. Operation in the “fan on” setting is usually utilized only to circulate air.
  • Pilot light out. If your furnace utilizes a standing pilot light, a safety sensor called a thermocouple constantly monitors the pilot flame. In the event the pilot flame goes out, the sensor cuts off the gas supply to the the main burner. The fan will still operate, but blow cold air.
  • Dirty flame sensor. Still another sensor monitors the state of the burner flame. If this sensor becomes coated with combustion residue, it may produce false readings and turn off gas to the main burner. This is usually the case when the furnace starts and briefly delivers heat, then blows cold air.

For fast service when your furnace blows cold air in the Richmond area, contact us at Gilman Heating & Cooling.

Where central heating ducts aren’t installed, ductless heating or a portable heater are two viable solutions. In many cases, extending ducts to a new add-on or remodel in an existing home is financially prohibitive or just not worth the disruption of opening up walls and ceilings.  Choosing between ductless heating or a portable heater involves drawing clear distinctions between the pros and cons of each.

Portable Heater Pros

  • Low upfront purchase price.
  • Transferable to different rooms as occupants move.
  • Eliminates cold spots without overheating the entire house.
  • Often the lowest operating costs to heat just one room.

Portable Heater Cons

  • Fire hazard and dangerous combustion gases from gas-fired space heaters.
  • Burn and fire hazard from heating elements in electric heaters.
  • Requirement for venting of gas-fired space heaters.
  • Unvented gas- or kerosene-fired space heaters should not be used indoors.

How does a ductless mini-split heat pump work? Ductless technology takes the best of central heating and cooling, subtracts the ductwork, and delivers safe, reliable comfort at a higher efficiency than a central system. A ductless heat pump incorporates an outside coil and compressor to extract heat energy from outdoor air. This heat is transferred to refrigerant and conveyed indoors in a small conduit to one or more wall- or ceiling-mounted air handlers incorporating a coil. Hot refrigerant warms the coil and the heat is dispersed into the room by a blower fan. In summer, the system reverses and the coils trade functions. Indoor heat is extracted, transferred outside and dispersed into outdoor air. Ductless Heating Pros

  • Heating and cooling in one unit.
  • No leaky or dirty ductwork to maintain.
  • High-efficiency in moderate climates.
  • Simplified installation – only a 3-inch hole in one exterior wall.
  • No issues with burns, fire hazards or dangerous emissions.

Ductless System Cons

  • In temperatures below freezing, the heating function activates supplemental electric heating that reduces efficiency.
  • Professional sizing of units is advised to avoid oversized or undersized installation.
  • Installation should be performed by specialists experienced with ductless units, not amateurs or DIY.
  • Costlier than portable heating at installation (but cheaper to operate over the long run)

For information about the benefits of ductless heating versus a portable heater, in the Richmond area contact us at Gilman Heating & Cooling.

If you’ve ever laid awake at night listening to the sound of a furnace turning on and off repeatedly, you know how monotonous and annoying it can be. You may also know it’s wasting money and decreasing household comfort as well. A furnace operates at optimum efficiency when all components remain at the steady, proper operating temperature. When the system cycles on and off rapidly, the quick heating and cooling of components degrades efficiency. In addition, rapid short cycles cause abrupt temperature fluctuations instead of evenly heating the living spaces in your home.

Here are some possible reasons why your furnace is turning on and off too much:


A new furnace upgrade that wasn’t properly sized for the thermal requirements of your home will frequently short cycle, turning on and off rapidly. All new installations should be preceded by a load calculation performed by an HVAC professional to accurately match the output of the furnace to the heating needs of the house.


When the internal temperature of the furnace exceeds design limits, a safety sensor called a high-limit switch automatically shuts down the furnace. After the unit cools, the switch will allow the furnace to activate again and the pattern will recur.

Overheating in a furnace is often a consequence of inadequate airflow. The most common cause of low airflow is a clogged air filter. Filters should be changed according to the manufacturer’s recommended interval.

Another reason for excessive heat build-up inside the furnace is a blocked exhaust vent. Birds nests, leaves or other debris may clog the vent pipe from the exterior. A blocked vent not only causes overheating, it increases the risk of dangerous carbon monoxide gas infiltrating your home.

Because of the fire hazard and health and safety issues posed by an overheating furnace, homeowners who notice short-cycling should schedule a furnace inspection with a reputable HVAC contractor.

For prompt professional diagnosis of a furnace turning on and off too frequently, contact us in Richmond at Gilman Heating & Cooling.

To keep your home's indoor air comfortable and healthy all year long, it's important to change air filters on a regular basis. If left unattended, your air filter will simply not work properly, allowing VOCs, allergens or other particulates to enter your home. Here are a few primary reasons why changing your air filter is so important.

Save Money on A/C Repair The workload of your air conditioner will increase dramatically as it tries to force air through a clogged filter, lowering your A/C unit's life span or damaging essential components. To avoid repairs or complete replacement of your air conditioner, check your air filter monthly and replace it as soon as dirt appears, or at least every three months. This will not only save you money on maintenance or repairs, but it will also work to lower your utility bills over time. Maintain Good Indoor Air Quality

Neglecting to change air filters will diminish the quality of your indoor air. As your air conditioner attempts to move outside air through an already dirty filter, the air that's being poorly circulated throughout your home won't be very clean. Young ones and your beloved pets are much more vulnerable to poor indoor air than adults. It's important to improve indoor air quality right away before volatile organic compounds (VOCs) or allergens begin to cause health problems for you or your family.

Help the Environment

Perhaps most importantly, in a global sense, changing air filters will work to lower your carbon footprint. Lessening the strain on your air conditioning system is great for saving energy and lowering the amount of pollution created from your A/C. For families who are environmentally conscious, something as seemingly insignificant as an air filter can make a big difference in helping lower your carbon emissions.

If you'd like to learn more about replacing air filters, improving indoor air quality or any aspect of your home's HVAC system, contact the experienced staff at Gilman Heating & Cooling. Our NATE-certified professionals offer 24-hour emergency assistance to homeowners throughout Ashland, Henrico, Hanover, Richmond, Glen Allen and Chesterfield.

Here in the Richmond area, homes can be heated and cooled efficiently with heat pumps. Due to our relatively moderate climate, either an air-source heat pump or a geothermal heat pump will work well, but each type has advantages and disadvantages. An air-source heat pump extracts energy for home heating from outdoor air, while a geothermal, or ground-source, heat pump extracts energy from an anti-freeze solution circulating in a loop of piping buried beneath the ground where temperatures remain constant throughout the year.

Heat pumps operate by removing heat from air in one place and releasing the heat into another place. For cooling, the system extracts heat from indoors and exhausts it to the outdoors, whereas in heating mode the process is reversed. Because a heat pump moves heat from one place to another, rather than generating heat by burning fuel, it can operate at extremely high energy efficiencies.

Air-Source Heat Pumps Versus Geothermal Heat Pumps

  • Cost - A geothermal heat pump costs several times as much as an air-source system to install. For a geothermal system, a drilling rig or trenching equipment buries the ground loop deep enough on the property to reach the soil's constant temperature zone. An air-source system simply requires an above-ground outdoor unit that looks similar to an air conditioner. Both types of heat pumps qualify for federal energy tax credits if you act by the end of 2013.
  • Outdoor temperature operating range - Air-source heat pumps won't operate at outdoor temperatures below about 30 degrees, so a home with an air-source system must be equipped with a backup furnace or electric heating coils for the coldest winter weather. Since a geothermal heat pump is sourced at a constant ground temperature in the mid-50s in the Richmond area, it can operate without a backup heat source.
  • Efficiency - Geothermal heat pumps are more energy-efficient than air-source systems. Their greater efficiency will pay back the higher initial cost over the life of the system.

For more information about heat pumps and their applicability to your home heating and cooling needs, contact the experts at Gilman Heating & Cooling.