The temperature that I set the thermostat on is never reached in the home . What is wrong with my home heating system?
You would think that this is way too broad a question to answer, but it is not. We have some presumptions that are required to answer this question. The first presumption is that the burners are firing. The second presumption is that the burners are staying on for the entire heating cycling. In other words the vents are putting out heat for the entire time that the thermostat is calling for heat.
I hope you noticed that I did not mention that the furnace is too small. While it is possibly that the furnace is too small to heat the home, I have never seen it. Our gas furnaces are typically twice as large as they need to be. Heat pumps are another ball game altogether and are not being covered on this page.
Broken Ducting
The number one source of lost btus for heating and cooling is the ducting. If your air ducting was installed pre-2000 it should be replaced and upgraded to a minimum of R8 and sealed with Panduit straps or some other form of mechanical fasteners. All joints and sheet metal connections should be sealed with a latex lagging adhesive and then the ducting should be checked for sealing by a licensed HERS rater.
If your ducting is leaking, they all leak, air outside the heating and cooling envelope of your home your home is drawing in replacement air from some other point of entry. It could be from under and around doors, windows, electrical connections, plumbing connections; kitchen vents hoods and bathroom exhaust fans. All of this air coming in to replace the air that your ducting is losing is unconditioned air and this unconditioned air could be the reason for you continuous furnace operation.
Outside Return Air Source
If you are getting you return air to your furnace from outside your home you should call right now and have us repair this. Let’s take a mild day of 42 degrees and a set point in the home of 72 degrees for heating. This means that all the air from outside the home that the furnace is drawing in must have a rise of 30 degrees minimum to even match the indoor temperature. All the gas it takes to get the first 30 degrees of heat rise is wasted heat. When your thermostat typically turns your furnace on the temperature has only dropped a maximum of 2 degrees. If you reheat the air in your home the air coming out the registers will be 28 degrees warmer in this example. That is a whole lot of heat.
Gas Pressure in the Furnace is Too Low
Contrary to popular belief the factory doesn’t always do it right. We have seen a vast array of gas valves where the gas pressure coming out the valve was too little and in some cases too much. Sometimes the differences in what the pressure is supposed to be and what it actually is are off by as much as 200%.
The Thermostat has a draft behind it.
Thermostats should not be located on the outside wall, near windows or doors or on an unsealed plumbing wall in the home. If you have a raised foundation the plumbing lines could come up through the floor, unsealed, and terminate through the attic, unsealed, and then through the roof. These hole sin bottom plate and top plates of the wall can create a thermal draft causing the cool air in the under floor space to rise to the attic. This creates a cold spot on the wall. If the open for the wires through the thermostat is not sealed this causes a draft right the thermostat and thermostat doesn’t have much of a chance at keeping an accurate temperature in the home.
Medical Issues
Over the last several decades that I have been working in the heating and air conditioning trades I have seen an increase in the number of medically induced complaints for heat. I have been to homes in the middle of the summer on a 90 degree day with the homeowner begging me to make their furnace work as they were very cold. The latest one in my memory is a grandmother in a home well over 100 degrees. Her makeup was literally melting and running down her face. I was panting in the home I was so uncomfortably hot. The thermostatic safety controls on the furnace would not allow the furnace to operate anymore as the temperature rise across the firebox exceeded the safe upper temperature working limits.
We can get the home warmer than 100 degrees, but to do so would require a note from your doctor and will require us to pipe hot water to a set of coils above the furnace rather than the furnace itself take on this task. It is highly unlikely that your doctor would sign off on heat this high. You may be comfortable, but the heat could cause a heat stroke.
The point is that heat is a perception of feeling and one person is comfortable at 65 degrees and another at 95 degrees. Humidity plays a large part in comfort. If you are finding that the thermostat temperature should make you feel comfortable, but you are not comfortable, then you probably are experiencing humidity levels that are too low unless medical issues are the reason. We can answer and solve those problems with poor relative humidity. |
