Inspecting HVAC Energy Efficiency for Inspectors Course

This open, public thread is dedicated exclusively for those students currently enrolled in InterNACHI’s free, online Inspecting HVAC Energy Efficiency for Inspectors Course. The course is open and free to all members, and can be taken again and again, without limit.

Students may:

  • write essays;
  • read other student’s posts;
  • discuss topics;
  • ask questions; and
  • share thoughts with other students.

Return to the course’s assignment slide.

Feel free to scroll through the students’ posts or jump to the last post to write something yourself.

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I recently inspected my own heating system in preparation for the upcoming heating season. The furnace is an American Standard, two stage variable speed, rated at up to 97% efficient. Replaced the filter. Everything else checked out ok, so should be ready for winter.

For the reading assignment I chose inspecting bathroom exhaust fans and inspecting kitchen exhaust fans. Both articles contained a lot of useful information. Through personal experience, i have found that anytime a fan is vented through an attic, in a cold climate, the vent should be wrapped with a minimum of r-8 insulation, to prevent condensation. I have also found that ,especially with range hoods, if the termination is through the roof, the condensation tends to drip down through the range hood. I always recommend over-running fans to make sure moisture is completely exhausted to the outdoors.

I am getting ready to begin ‘Inspecting HVAC Energy Efficiency.’ Looking forward to the study along with everyone else taking the course.

Mike Flowers
Mike’s Home Inspection Services, Inc.
Americus, Georgia

Did an inspection of the HVAC system in the attic. The duct was secure as well as the insulation. There appeared to no damage and the main runs were well supported and secure. All the connection points to the registers were well insulated and there was no evidence of condensation or moisture problems.

Also inspected the ‘Whole House Fan’ (Attic Fan). It is secure and operates correctly with all louvers opening and closely properly. It was correctly installed to cover, fit inside the ceiling joists and is secured to the ceiling joists for a nice sealed fit. Therefore none of the attic structure has been compromised during its installation.

Nick, I have an digital image of the whole house fan, but any attempts to upload the image has failed. I have attempted 3-5 times to upload my image of the whole house fan and each time the upload has failed. I have tried logging out of the course and logging back in and it still will not upload the image.

Mike Flowers
Mike’s Home Inspection Services, Inc.

Hello Everyone. Trust your course studies have gone well and you are close to taking your final exam. I am looking forward to the exam. The two articles I have chosen to give a report on are, ‘Identifying and Describing Heating Systems’ and ‘Passive Solar Building Design.’

The First Article Read: ‘Identifying and Describing Heating Systems.’
When it comes to heating systems, inspecting them and even determining their efficiency regarding energy loss, we as inspectors learn that every heating system has its own characteristics and can described in 4 broad categories.

  1. The heat-conveying medium - what carries the heat from the source to the enclosure being heated. Those mediums for carrying heat are air, water, steam and electricity.
  2. The fuel that is used for the heating system is a distinguishing characteristic. This can be wood, coal, oil, natural gas, kerosene, pellets and gas. Even though electricity is considered a fuel it could also be the heat-conveying medium.
  3. The next characteristic would be the nature of the heat. One example would be steam, or heat produced by combustion.
  4. The final characteristic would be the efficiency and capacity of the heating system. This can be helpful in identifying and describing the heat system.

The article points out four types of heating systems. There is the ‘warm-air’, ‘hydronic’, ‘steam’ and electric heating systems. Most heating systems can be identified and described using one of these four terms, which are based on the four heat-conveying mediums earlier described.

The article finishes with this important statement about identifying the type fuel the system uses: "Stating the type of heating fuel being used is essential to accurately identifying and describing the inspected heating system.

The second article: ‘Passive Solar Building Design’
The article begins describing the passive solar building “as a strategy by which a building’s windows, walls and floors can be designed to collect, store and distribute solar energy in the form of heat in the winter’ and vent solar heat in the summer.” Passive solar heat techniques can be applied in new construction, which is ideal, or in existing buildings where it can retrofitted.

There are 5 principles incorporated in the passive solar design: 1) There is glazing or aperture, which sunlight enters the building. 2) The next principle is absorber, or the surface of the heat-storage element that sits in the direct path of incoming sunlight like dark floors or masonry walls. 3) Material that retains the heat converted from sunlight is called thermal mass. 4) Distribution, or the method by which heat circulates throughout the building from its point of collection. Ducts, fans and blowers may be implemented to assist in the distribution. 5) The last is called ‘control.’ Some means of control will prevent overheating during the summer months, or whenever the passive heating system need not operate unimpeded.

Successive passive solar design, applies these principles in one or more techniques as the article points out:

  1. Direct gain is the simplest design, which is sunlight through the windows without interference.
  2. Indirect-gain is a technique by which the thermal energy is stored in an area adjacent to (but not a part of) the living space.
  3. Isolated gain involves utilizing solar energy to passively move heat from or to the living space using a fluid, such as water or air, by natural convection or forced convection.

The article ends with this summary statement, “passive solar building design techniques in either old or new construction use simple, inexpensive ways to heat and cool a building.”

Good articles that I would recommend the energy wise inspector to read.
Thanks for allowing me to share.
Mike Flowers
Mike’s Home Inspection Services, Inc.
Americus, Georgia

I inspected a house in North Branch, MN last week. This is the view of the attic. The owner was telling me that the buyer was wasting money on an inspection because there was nothing wrong with the house.
As you can see, the insulation is uneven and has kraft paper on the outside. Moisture could get trapped beneath the paper, and the gaps between the bats will let heat right through.


his house also had a whole house fan that had been installed in the attic hatch, (making the access to the attic a bit of a challenge). The fan actually directed warm, moist air into attic space. These installations are only recommended where the air is very dry.

This class was super informative. Whoever the people are that come up with all of the different HVAC systems are geniuses. And I feel much more informed about all of these systems after taking this course. When doing inspections, I feel that I will be able to help my clients much more than I was able to before, due to all of the knowledge that I gained by taking this class.

Well the system of choice for THIS session was obvious – the HVAC system. So I went to my basement and decided to see if I could find any issues with my ductwork – not the technical, mechanical parts of my furnace – just the ductwork. And I was surprised to find multiple problems. As this picture exemplifies, I have many places where my ductwork is not taped. There are supply ducts not connected well to the main trunk. There are places on the cold air return where the sheet metal was fastened to the underside of the joists, and it USED TO BE taped but the tape has long since been removed or just came loose. I used to look at things like this and conclude that it really didn’t matter – that is just that much air that will leak into my basement, but since hot air rises, I’m really not losing anything. This course has corrected that line of thought by showing the importance of all systems being maximized in their efficiency!

I somewhat kept with the theme of this course when choosing these two articles: Central Air Conditioning System Inspection, and Central Humidifiers. The first article contained lots of information on Central A/C Inspections, not all of which I found to be repetitive! For example, I don’t recall being told to remove the cover and clean the exterior unit, or to comb the bent fins. The part on Central Humidifiers that caught my attention was that indoor air that is too dry can cause damage to musical instruments, dry skin, peeling wallpaper, etc. More significantly, I didn’t know that the humidistats on Central Humidifiers had to be adjusted daily! This leaves me wondering if anyone really has one which works as intended, because I certainly don’t know anyone who would give daily attention to such a mechanism!!!

Attached is a photo of a new Air Handler install. The old AHU had a leak in the coils. this unit does not have heat as I do not use it in the winter. after this course and others on HVAC and ventilation I have reduced my energy bill by increasing air circulation by leaving doors open to rooms not being used. the closed doors were causing an issue with the air return as those rooms did not have dedicated air returns. I also implemented fans in the house which has helped keep the house cooler. the other photo is the energy rating for the AHU. As can be seen the AFUE of the unit is 100. its amazing to see that many little changes have a big affect on energy usage. I am now looking to increase my certifications with BPI or RESNET.

I took this photo in the crawlspace of a single family home the other day. The crawlspace was open to both the basement as well as to the tuck-under style garage. As you can see from the photo warm/moist air from the crawlspace is condensing on the HVAC supply duct; the upside down f’glass batts are hanging down from the floor joist channels; the EPS foamboard on the foundation walls is damaged; there’s an open 6" air duct in the crawl and in general it is a nasty, dangerous, and inefficient mess. It never ceases to amaze me how otherwise intelligent people live in their homes without so much as a thought to Indoor Air Quality, Energy Efficiency, and Optimized Comfort. It would take too much money in order to make some tremendous improvements in this home. I find that, at most homes we inspect, people take far better care of their vehicles than they do of their homes…and don’t get me started on the way they pamper their dogs!

I chose “Increasing Home Energy Efficiency” for one article and “Disadvantages of Solar Energy” as my other read.

Not much new to read but its good to be reminded of things from time to time.

Increasing energy efficiency is within the means of most people, find and plug air leaks is one easy to do fix. Another would be when remodeling to purchase energy efficient products and learn why U factors are important when buying windows.

Other less expensive savings can be found by sealing cracks, wrapping your water heater and switching to light bulbs that are more efficient than incandescent bulbs.

I include a picture of an electric supplemental forced air furnace, the main furnace is a Gemini wood burner.





As a requirement, I read “Elements of an Energy Efficient House”.It
describes the alternative wall assemblies that are being used to make homes more energy efficient. The two systems I found interesting were SIP and ICF`s. The SIP is a wall section sided with OSB and have solid core insulation in the center. The ICF is actually a form constructed Of solid core insulation with concrete poured in the center.

I also read ,“Energy Efficient Mortgages”. The FHA, Fannie Mae ,Freddie Mac and private banks offer this kind of loan.
EEM loans are offered because they increase the value of the property because they are more energy efficient. On securing one of the loans they also allow the borrower to qualify for a larger mortgage amount because their interest rate is lower.

This is a condenser that I was able to view . Its a 1.5 ton Trane unit that was installed in 2002 . I looks to be in decent shape for its age.
I can see its original because there is no filter on the refrigerant line.

This is a home that I inspected in Tampa, Florida. The HVAC coils were extremely dirty and needed cleaning. The same was true for much of the home. The return vents were all dirty and the attic was coated in a layer of dust and dirt. The home had lots of areas allowing outside air to the inside. One side of the house had no vegetation and was all dirt which was creating lots of dust during grass cutting and high winds. It was recommended to seal off some of the areas where air was leaking into the home. It was also recommended that grass be planted in the bare areas of the yard.


The two articles that I chose to read for the “Inspecting HVAC Energy Efficiency” course were “10 Easy Ways to Save Money & Energy in Your Home” and “Condensation in Double-Paned Windows”. I chose the 10 easy ways article as it seemed to go well with the course. It was a good article to help with my knowledge on tips to save energy. It reinforced some of the lessons from the online course and helped give me ideas on things to say to a customer when talking about home energy and saving money. The articles on condensation in windows was chosen to help me understand more ways that double pane windows fail. This will also allow me to better interact with customers. I enjoy the articles and getting new ideas on how to improve my customer service and grow my business.

The two articles I chose to read were:

How to Inspect the Refrigerator
by Nick Gromicko and Ben Gromicko
Power Strips: Their Uses and Hazards
by Nick Gromicko

I found both articles to be very well written and informative. The first article talked about how an inspector is not required to inspect or move an appliance, though some states require it, and even more inspectors offer it as part of their standard home inspection. Those who do inspect refrigerators must check for rust, damaged & missing components, excessive ice formation, as well as numerous other potentially hazardous problems. The second article went into great detail on the potential defective conditions power strips may be found in. This includes, as just a few examples: daisy-chaining (plugging power strips into other power strips), overloading (having too many high power appliances plugged into the some area), or something as simple as wound or knotted cords. Both articles have a lot of good information in regards to the safe inspection of electrical equipment and supply.

Kevin Schieferstein

Attached is the photo of a condenser unit at a property I inspected last week. This particular unit, which was updated in 2006 along with the natural gas, forced air (90%) furnace (which has a damaged filter), needs cleaned and leveled. It also had missing insulation on the A/C suction line at the plenum area. While these issues are pretty standard, they still need addressed as soon as possible.