I strongly advise clearing snow and or ice from A/C condensing units. This was taken at a recent inspection in Washington State. This is, and older unit as viewed by the rust on the condenser top. The unit is a heat pump and was tested on the heat side only. The exterior temperature was about 12 degrees F. The heat side functioned as expected. The buyer was educated as to the reason for not running the cold or A/C side with such temperatures. As always, a complete cleaning, service and inspection by a qualified HVAC professional was advised.
Paul E LeRoy
Inspector/ owner
Prime Home Inspections, LLC
509-222-9816
The filter compartment does not have a cover. There should be a removable cap to cover the filter compartment. The open compartment could draw supply air from the utility room creating negative pressure. The negative pressure could possibly draw the flue gases from the gas water heater into the utility room.
This picture is a heat pump condenser. The house is under construction with the disconnect removed from the wall. The unit will require evaluation by a mechanical contractor as well as a licensed electrician. There is no way to test operation.
Steel Houses
There are more than 3,500 different grades of steel. Most have been developed within the last few decades. China is the worlds top steel producer, followed by Japan, Russia, and the United States. Steel is highly recyclable. In the United States more steel is recycled than plastic, glass and aluminum combined, making it the most recycled material nationally. There are three reasons for this, first, by virtue of its magnetic properties, steel can be easily separated from the waste stream. Second, recycling saves the steel industry huge amounts of energy, enough to power 18 million homes for one year. Third, recycled steel loses none of its properties, making the recycling process simple and efficient.
Type B vents can only be used for gas fired appliances. They cannot be used for any appliance that produces flue gasses that exceed 480 degrees fahrenheit. Combustible material clearances are between 1 and 2 inches. These clearances are stamped on the vent’s exterior metal surface.
On this high efficiency furnace the flames are in good working condition when the furnace was started. The float in the pan around the unit was tested to ensure it would shut down properly, which it did. There was a note on the inspection report that was added that needed to reviewed by a certified professional. (It was not secured properly and was hanging down waste high and had to be walked across to get to the water heater)
In the article I read on Inspecting Furnaces it gave great detail and simplified a few things I was struggling with. Now I feel comfortable explaining to a client the type of furnace, fuel, airflow (gravity or forced warm air) ignition.
This photo is of a high efficiency furnace, that has the combustion intake line disconnected. Generally you can pull combustion air from the interior, provided there is plenty of combustion air available. I recommend drawing combustion air from outside he home. In some homes, furnace enclosures rarely have enough open air space to meet BTU requirements.
First impression just walking up to the furnace is the following. It is a gas high efficiency furnace. It is missing a drip leg and it appears to have some form or corrosion building up on the top of the cabinet.
As an inspector you should never test an A/C unit when the temperature is below 60 degrees. A more accurate and more safe way to think about this is to never run an A/C when then inside temperature is warmer than the outside temperature. When this happens the refrigerant condenses outside instead of inside and can damage the compressor.
Picture is a Trane XV80 upflow forced air natural gas furnace, model number TUD28080A93v3BA, serial number 122345GL1G located in a condominium utility room. Furnace was manufactured in June 2012. Input rating was 80,000 BTUs/hr. Unit was rated for a minimum overcurrent protection of 15 amps. Furnace was clean and functional. No issues were found.
“Identifying and Describing Heating Systems” describes how to identify and describe most heating systems in four ways that enable the inspector to comply with the InterNACHI Standards of Practice that states “a home inspector shall describe and identify, in written format, the inspected systems and components of a dwelling”.
The four ways are: 1. Heat conveying method
2. Fuel used
3. Nature of the heat
4. Efficiency and Capacity
However, other characteristics and details are needed in order to more accurately and concisely describe the system in a easily understood manner.
Here we have a standard B-vent too close too combustibles along the lower right side of the roof opening. The was called out as a potential fire hazard as a result. You will also notice the light coming through the rain cap connection that was loose and the cap had become dislodged.
Its easy and beneficial to teach home owners about standard maintenance of appliances as part our inspections. One way could be as simple as keeping the efficiency of a condensing unit up par by as simple as using a garden hose. The top cover plate can be easily removed and the coils hosed off. This will keep the coils free of dirt and debris and is one way to help keep the refrigerant system balanced.
After completing the advanced HVAC InterNACHI course I have learned about all sorts of different furnace efficiency systems and some of the positives and negatives that come along side them. I have attached an image of a high efficiency furnace system that is having a leak due to condensation coming back in from exhaust air. High-efficiency furnaces are equipped with a cool exhaust. Because of this, condensation is formed. You can tell if your furnace is high-efficiency by looking at your vent pipe; if it’s white plastic (PVC), your furnace is a high-efficiency model. Usually, the condensation in high-efficiency furnaces gets channeled into a floor drain. If you have a leak, it could be because the tubing for the condensation has become clogged or cracked. The drain in the floor might also be clogged. This can be prevented by regular maintenance to your high efficiency furnace system. As a general upgrade tip for people with high efficiency furnace systems a secondary drip loop & drain line can be installed into the exhaust vent to help redirect water away from the inside mechanical system.
After reading & studying the InterNACHI article on inspecting for proper installation of HVAC filters I have learned that Most homes have some sort of furnace or heat pump, and many of those homes (especially newer ones) have combined heating, ventilation and air-conditioning or HVAC systems. Each type uses some type of air filter or screen to prevent larger airborne particles (up to 40 microns) from entering the system and clogging sensitive machinery. A system that has a dirty filter can suffer from pressure drop, which can lead to reduced air flow, or blow-out, resulting in no air infiltration at all. Any of these conditions can cause the system to work harder to keep the home warm or cool (depending on the season and the setting). And any mechanical component that has to work harder to run efficiently puts undue stress on the whole system, which can lead to premature failure, resulting in repair or replacement.
Also, a dirty filter thats exposed to condensation can become damp, which can lead to mold growth that can be spread throughout the home by the HVAC system. This can lead to serious health consequences, not to mention a compromised unit that will likely require servicing and may require replacement, depending on the severity of the moisture problem.
This is a photo of an old furnace from one of my previous inspections. As seen in the photo, it is in very poor condition, with severe rust/corrosion/damage. This old unit was still working at the time of the inspection. It was later found to be unsafe, after the client followed my advice on having it examined by a licensed HVAC technician and budgeting for replacement.
I viewed the illustration of an air distribution system. The supply duct carries air from the air handler and distributes it to different rooms throughout the home. The return duct carries air from the conditioned space back to the air handler.
THE ATTACHED PICTURE WHERE THERE WAS NOT ENOUGH AIR MOVEMENT THROUGH THE DUCTS TO COOL SOME OF THE BEDROOMS. WHEN I OPENED THIS ATTCIC SPACE I DISCOVERED ALL OF THE DUCTS THROWN, AND NOT SUSPENDED. UPON FURTHER INSPECTION, THE DUCTS WERE REDUCED AND TAPED TOGETHER TO REACH SOME AREAS OF THE HOUSE. ONE OF THE DUCTS WAS KINKED, MAKING IT DIFFICULT FOR THE AIR TO PASS THROUGH.
STROLLING THROUGH THE INTERNACHI PHOTO GALLERY I STUDIED A PICTURE SHOWING THE CORRECT WAYS TO SUPPORT FLEX DUCTS. ACCORDING TO THE ILLUSTRATION, IF SUSPENDING THE DUCTS THEY SHOULD SUSPEND ON 1.5 INCH WIDTH HANGERS, AND THEY SHOULD BE SPACED 4’ APART, WITH A MAXIMUM SAG OF 1/2 INCH PER FOOT. VERTICAL DUCTS SHOULD BE STABILIZED BY SUPPORT STRAPS SPACED NO MORE THAN 6 FEET APART. DUCTS SHOULD HAVE A SUPPORT STRAP BETWEEN A METAL CONNECTION AND A BEND IN ORDER TO ALLOW THE DUCT TO EXTEND STRAIGHT FOR A FEW INCHES BEFORE THE BEND. IF NOT SUSPENDED, FLEX DUCTS CAN REST ON CEILING JOISTS OR TRUSSES IN DRY CLIMATES IF SUPPORTED EVERY 4 FEET.
