How to House Hunt Like a Home Inspector Heating Part 1
In this series we’re looking at how prospective home buyers can look at the home’s systems with the eyes, or at least the approach of a home inspector to learn more about the house. In this installment, we’ll start looking at heating systems. But this is a huge topic because there are so many types of heating systems. We’ll discuss everything from electric space heaters to fireplaces and wood stoves to furnaces and boilers, but not all today.
Let’s consider heating as two groups of systems: Those that generate heat and distribute it throughout a home, and those that generate and deliver heat in the same location. We’ll consider the first group today. This group includes furnaces that deliver heated air through ducts and registers, and boilers that deliver hot water or steam through pipes to radiators, baseboards or convectors (wall mounted units similar to radiators that can serve heating and/or cooling systems) or through radiant heating pipes. The energy source for the furnace or boiler can be gas, oil, electricity or even wood. We’ll skip wood for the time being.
When you’re looking for a house there are some things you can do to assess these kinds of heating systems. The first is to simply determine the heating needs in the region you are moving to. In Canada, where I live, all houses need to be heated part of the year. The size of the house, the typical weather conditions and your lifestyle all play a part in the size and type of heating system you will want. The costs of different energy sources and greenhouse gas emissions are becoming increasingly important as well. In general, although you won’t need it every day, you want a heating system that will be sufficient to keep you and your family warm on the coldest day of the year.
As you’re walking through a house, look for a heat supply to every part of the house. You’ll look for registers for forced air systems or radiators, convectors or baseboards for water or steam systems. If the furnace or boiler isn’t delivering heat to a room, the occupants of the room won’t be comfortable, especially in the cold Canadian Prairie winters where I grew up. When a furnace supplies warm air through registers, be sure that there is an opportunity for air to escape the room as well. This is usually a cold air return grille that returns to the furnace through the return ducts. But if this is absent in room in an older home, be sure that the door has a gap at the bottom to allow air to be pushed out into the rest of the home. If there is no way for air to get out of the room, air pressure inside the room can increase and prevent the warm air from getting into the room.
If you are looking for a house during the winter season, be aware of the temperature of different rooms. If heat is being delivered to some parts of the house but not others, you can often tell, depending on how severe your winter is. This can be due to a poorly designed duct system, or damaged or disconnected ducts or plugged pipes. Cold floors near the exterior walls are another problem to look for, but this is often related to the insulation and vapour barrier rather than the heating system.
Where hot water or steam heat is used, especially in an old home, it is not uncommon to find rooms that are not served through a radiator, convector or baseboard unit. In these rooms be sure to look for a thermostat or an indication that another heat supply like radiant (in-floor or ceiling) or electric baseboard heat is present. If there is no heat supply to the room, you may want to consider the cost of adding it when you consider the purchase price, or invest heavily in some warm quilts.
Digging a little deeper, you can look at the source of the heat, the furnace or boiler. The first thing you should be looking for is the condition of the unit. Is it dirty, damaged, rusted, or scorched? Does it look new or old? Consider how the energy source is getting to the furnace or boiler. If gas, take a look at the gas pipes for any obvious issues or damage. If oil, you must consider the delivery pipe and the storage tank (in a few areas municipal oil supply pipes supply the oil but this is not usually the case). Oil tank removal can be a big environment concern if buried outside, but still carries some cost if inside the home. There is also a risk of leaks if inside the house. Any sign of damage, leaks, corrosion, or even just poor support are things you should be concerned about.
If it’s an electric furnace, the condition of the cabinet doesn’t always tell you everything. It is generally better (and safer) if a furnace has been maintained and cleaned regularly. But, electric furnaces are a bit tricky to predict. There can be reduced capacity (less heat produced) if individual elements fail but total failure can occur without warning signs. They generally last until they don’t. If it looks quite old, you can factor that into the cost of buying and living in the home. But you might, maybe, perhaps get many more years out of the furnace. But there is no heat exchanger in an electric unit as there is in a combustion (gas, oil or wood) furnaces or boilers, so you don’t have to worry about poor performance having the same health risks.
In combustion based units, we have to think about the elements of combustion. Fuel, fire and oxygen combine to produce heat and combustion gases including carbon monoxide and water (in the form of steam). If the unit is igniting, there is fire and probably a good fuel source. Furnaces are designed to separate the house air that circulates to warm the house, from the hot combustion gases. They transfer the heat through a heat exchanger that separates the two. This is often a coated metal sheet that is shaped to make the air on either side flow along passages that transfer as much heat as possible. In boilers, the heat is transferred to water that distributes the heat. In either case, there must be a good venting system to remove the toxic combustion gases from the house. Look for vents above the units that are poorly supported, disconnected, damaged or rusted. These will require improvement and may be a sign that furnace or boiler replacement is required. In newer high efficiency units there may only be plastic pipes that bring fresh air from outside and take the combustion gases (which are typically not as hot as in conventional units) out.
Looking for a scorched cabinet was mentioned earlier. This could be a sign that the heat exchanger has developed a hole and hot combustion gas is escaping. Or it could be a sign that there is a problem at the burner and the flames are directed where they shouldn’t be. Air supply can also be an issue if it draws house air to supply the flame (newer high efficiency sealed combustion units bring outside air to supply the flame). If there is insufficient house air getting to the flame the result will be poor, inefficient combustion. But worse, it can cause low pressure in the house resulting in combustion gases being directed into the house instead of up the chimney. This can be dangerous. Look for older units in small spaces with no grilles allowing air in.
But be careful making any assumptions about furnaces and boilers, especially combustion based units. These are complicated devices that have intricate designs that the layperson won’t be able to understand completely. Look for the warning signs, but always get someone with more expertise to evaluate before you make any definite judgements. Some units in situations that look questionable are designed to operate under those conditions and perform very well. Other units that look beautiful may not be functioning correctly for a variety of reasons that only a specialist will be able to identify.
A home inspector will take the visual inspection done by an astute home buyer and raise it to a higher level. Details about position and support of vents and ducts, clearances from flammable materials, appropriateness of the materials themselves are items the home inspector should have studied and learned through experience. Looking at the furnace or boiler itself, the home inspector will remove the covers to look at as much of the burners and heat exchanger as they can. They’ll look at the blower fan, belts and motor for signs of any issues. They’ll assess the performance of the venting system and look for signs that the chimney liner is in distress or has failed. They’ll usually be able to determine the age of the unit and provide some advice about how long the unit will typically last. They probably won’t give a very precise number of years though. No one can predict the future with heating systems.
Finally, they will usually be able to determine the capacity of the system and may make a comment on whether the unit is considered sufficient for climatic conditions typically seen in the region.
But heating systems are complicated, variable and changing all the time. Codes relating to how they are configured are also changing. It’s hard to keep up with all the details, so wherever something is questionable, a good home inspector will defer to HVAC (Heating ventilation air conditioning) specialists. A trained HVAC technician will go much farther than a home inspector can. The HVAC technician has the specialized knowledge to completely dismantle the system and assess all the parts. They are trained in the design of air distribution systems. They know when a vent or a duct system is not configured properly and how to correct it to make the home safer or to make sure the system is operating efficiently and providing the best comfort to the occupants.
Steven Schroeder 2016-10-16