I was looking to beef up my offerings for standard energy audit and feel like some quick screening tests for HVAC would be great. The only test I currently do is a dominate duct test.
Since I am lacking on the HVAC knowledge side, I would also like to know how to interpret those tests - I am sure someone will suggest a static pressure test - so, how do you perform and what is normal and what actions do you recommend for results outside of normal.
I can do a blower door test, and IR scan and a flow hood round in 45-60 minutes. A quick look at the bill and out of the house in 1-1/2 hours. This is just a comfort diagnostic and not a BPI audit. I don't want to do static pressure (my staff is told not to do them even though they have and understand them) because, as stated earlier, I don't want to drill a coil.
Ed, I think some furnaces simply (and literally) scream for ESP. It takes 3 minutes, and can really help design. I hate being at design stage and having questions about simple things. One less thing to guess about. I bought a Testo manometer for the purpose, and for room to room when the interview uncovers problems in very specific locations I'm trying to get my head around. I'm not a DG700 whiz (unlike http://bit.ly/rickchitwood), and prefer to leave that to manage cruise control.
I'm not typically done with my interview until the 90 minute mark. When I was just "selling" audits and not performing them, I was usually in the house 2.5-3 hours.
If I'm gonna spend a bunch of time scheduling, then going to someone's house, I want to get as much out of the visit as I can. And I don't want to miss something critical that might mean the difference between winning and losing.
It takes most people hearing something 7 times before it sinks in. So if I say something 4 times on the first visit, we are half way there.
My auditor and I had a GREAT relationship, we significantly overlapped which meant really collaborative design process, and big jobs (12-60k with 20-30 being the most common range). The information I gathered often meant he didn't have to go back because he missed something, and vice versa.
And I think by having people feel they really understand the logic behind design, and feel it was really tailored to meet their needs, makes them much more comfortable signing big contracts.
on the side of the furnace is listed the temp rise, Most/all furnace that have high static pressure will also have high temp and will go on off the high temp switch. This switch is on all 80% and 90% gas and LP gas is listed the what the top temp is. I take out the high temp switch and do a static pressure test BUT I do this all the time for 30 yr. If you do it hot you can and will short the low volt fuse so know your stuff before working on furnaces. If I do a quick temp test I take out a screw and put in a "K" wire then read off my test meter. I bench mark the furnace with 4 temps and CO
There are a bunch of things you can do to evaluate an HVAC system. A static pressure test is a good one for getting a grip on air flow BUT the industry is now saying (and correctly so) that the air handler and any associated coils need to be as clean as "new". This is a good call because the blower CFM data is set by testing "new" units. The most you could get from a static pressure test without cleaning everything (blower & coil) is whether or not it is performing to specs. If not then it's time for the deeper look or a call to your local HVAC shop.
Checking performance of a HVAC system includes a lot of options depending on many variables. The best approach is to work through the entire system...looking at everything. We don't see too many Home Performance folks coming in to learn HVAC but we do see a lot of HVAC folks coming in to learn Home Performance. If you are interested in getting deeper into HVAC we have many courses and programs that take you there @ www.hvacredu.net
All are BPI recognized.
Thanks for asking.
Some great info here I can easily use.
I really happy to hear your concern about your HVAC machine. Thanks for sharing your ideas.
You can do one of the easiest tests to measure the rise and falls in temperature of air conditioner, evaporator coil and the heat exchanger of a furnace or a heat pump. You should also do a duct test but do not try to do a static pressure test yourself until learn from an expert air conditioning technician. The test is very easy. And if you have any issues then you should contact your nearest HVAC contractor.