"Like Italy in the 1960s", HVAC contractors have no idea how to build to California's Energy Code.

A lovely guest house in the country. Brand new, white, gleaming and beautiful. The owner is British. I tested the performance of her new HVAC system. It failed three HERS tests.

I explained to her each of the tests and why the system failed. The ducts leaked too much air. The system did not move enough air for the size of the air conditioner. Why? The return ducts are either too few or too small. The MERV 8 filter installed is restricting air flow so it should be bigger or perhaps there should be two of them. The 2017, airtight, well insulated 1500 square foot house with low e, argon dual pane windows doesn't take much to heat or cool. How did it end up with a 3 ton AC and restricted, leaky ducts?

The homeowner told me that it was "like Italy in the 1960s." A top-heavy bureaucracy well insulated from those doing the actual work or needing to get things done. The individual people are often brilliant, but people are not working together. Some were also incompetent.

We have a real problem in the SF Bay area with HVAC contractors installing air conditioning systems without following the CA energy code's "Mandatory Measures", nor CalGreen. Every day I test new systems that have not been sized and designed as per code requirements. This yields systems that use more energy and provide less comfort. This has a real effect on energy use in the SF Bay Area. These improperly designed system can last 30 years or more and will waste energy daily 'til near 2050 when they will fail.

California Title 24 Energy experts say that 1% of residential HVAC systems are properly calculated for sizing and have their ducts designed per the specs in Title 24. Only 10% get permitted and tested.

Of course, the Energy Commission did not make up these design specs. They use the Air Conditioner Contractor's of America Manual J, Manual D and Manual S sizing, duct and register grill design specifications.

Sadly, there is no continuing education from the Contractors State License Board for HVAC contractors. Hence, they have no idea of what is in the California Energy Code or how to build comfort system that conform to it.

We are now in the 2016 energy code. Builders and HVAC contractors are nowhere near understanding what is in the current code or how to meet it. At the same time we are nearly 2 years away from the 2020 energy code when new buildings will be "Zero Net Energy", meaning that houses will generate as much energy in a year as they use in a year. We have a lot of work to do to educate the building industry workforce in order to get up to speed with upcoming code changes.

Let's fix this problem.  Just like engineers design our building so they stand up to earthquakes via code required structural design, let's have our HVAC systems engineered per our energy code. We need to require building department design review first, before permitting these long lasting, energy using systems to get built.

CSLB and California local Building Departments, please get up to speed educating the building industry workforce and enforcing the energy code.

George Matthews, owner
Building Energy Compliance Testing
Serving the San Francisco Bay Area

Failed HERS Test and Final Inspection - How to Avoid the Pain and Expense and a Solution to the Problem

It happened again, yesterday, doing a HERS test on a new house, HERS testing the air conditioning system.
This was the third time I was at this house testing. The technician, not an HVAC contractor but a tech hired by the owner, had added another duct to coax the 5 ton air conditioner into blowing 1750 cubic feet of air per minute, the minimum required by code.

The system did not perform to code. It moved 1600 CFM but not the 1750 required by the State of California. We looked at his work. He'd added a shiny silver drooping limp flex duct connected to a small return filter box. He told me there was nothing more he could do. I suggested pulling it taught in a straight line to the return. He didn't think that would work. He really did not like my alt suggestion of a straight metal duct to reduce air friction.

I exited the front door with him. He threw is boots hard at the driveway and cursed in anger. I could sense deep frustration and a man who probably won't get paid until the job passes. I felt sorry for him. He did not know that these systems are supposed to be sized according to manual J, Manual D and Manual S in software such as Wrightsoft. The owner or builder had signed off on building to the Calgreen checklist which states that the HVAC system will be sized according to Manual J, D and S. Apparently, no one took that seriously. The City of Orinda building department never asked for this basic engineering. Hence, it never got done.

The technician had guessed the system together. The 2600 square foot house in mild, often foggy Orinda, California somehow received a 5 ton air conditioner, the largest available. When it failed he asked me what to do. I had to tell him that I am not the designer but the State's Energy Commission does have something called the Building HVAC Requirements.  http://www.energy.ca.gov/2013publications/CEC-400-2013-001/chapters/04_Building_HVAC_Requirements.pdf

In these Building HVAC Requirements, under table 4-11 (Standards Table 150-D): Return Duct Sizing for Multiple Return Duct Systems, there is a line that shows a 5 ton air conditioning duct system having two 20 inch return ducts with a minimum gross filter grill face area of 1500 square inches.

The system I was testing did not have anywhere near 1500 square inches of filter grill face. It had two filters equaling 768 square inches, about half what code is requiring.

If this system had actually been designed rather than guessed together by a person using some "rules of thumb", it most probably would have passed the first time. The problem is that this is the 3rd time I've seen this in a ten days. It happens all the time in the affluent, well educated San Francisco bay area, home to so much energy efficiency research and development.

I usually ask air conditioner contractors how they sized the system I'm about to test. Almost invariably they tell me they use the "square footage rule". "What is that?" I ask. They then explain that for every 500 square feet of house they put in a ton of AC. Easy! 2500 square feet of house equals 5 tons of AC. System sizing complete! Sometimes they admit that the guy at the supply house told them what size was needed.

We know the problem. HVAC contractors and unlicensed technicians who install HVAC systems don't size those systems according to protocol of the Air Conditioning Contractors of America. The results are brand new, shiny yet poorly operating systems that will waste energy and perform poorly for decades to come.

Here's the solution. City Building Departments must get manual J, D and S designs before contractors can build that system. Just as seismic engineering is required for buildings before they are built, so to can we require that mechanical systems be engineered before they are built. Then we just have to work with the problem that the residential HVAC industry evades building departments permits and code HERS testing some 90% of the time.