Hello I could use sum advice on whether to use Prestons Guide on HVAC or to use Carson Dunlops Reference? I’m new to the buisness and would like to know you guys use.Thanks Virgil
I will be honest in saying that I have both and like both of them. To me having both is worth the money.
Randy
I agree Randy. Preston’s sometimes fails to have the information I’m looking for, that’s where I look to Carson Dunlop for the answer and usually find it. Both are well worth the cost.
Carson Dunlop verses Prestons?
Absolutely go with Carson Dunlop.
I’ve ben lost with Prestons since day one.
Must be an age thing Dave 
Preston’s and Dunlop’s guides are like
night and day,
yin and yang,
hot and cold,
stop and go,
sun and moon,
father and son,
mother and daughter,
Will and Grace,
Sonny and Cher,
King George I and King George II,
Clinton and Obama,
Rodgers and Hammerstein,
Lennon and McCartney,
Simon and Garfunkel,
Aggies and Longhorns,
iNACHI and ASHI,
Tom Petty and The Heartbreakers,
Elton John and Bernie Taupin,
Brad Pitt and Jennifer Anniston (oops),
The Beatles and The Rolling Stones,
Ohio State and Michigan,
Duke and North Carolina,
Hewlett and Packard,
The Fast and The Furious,
…
You can’t have one without the other.
I have both & the Carrier Blue Book. Find most stuff in Prestons Guides
if you can’t have one with out the other, then where can a person get these?
Check Amazon or simply do a websearch. There are many ‘technical’ book/manual sites available.
CD books are available from the CD website.
Nolan Kienitz
Dallas Home Inspector
Can’t speak for Prestons but I have taken heating I, heating II and heat pumps/air conditioners with Carson Dunlop. Highly recommend those three courses, very complete and detailed.
I had all three gave my Preston away have C&D with me but never open it .
I can usually get the year from the equipment and if I can not I give my idea of the age ~.
I wonder why so many are so concerned with the actual age of a furnace .
I live in Canada and if it is old Thats how I report it and move on.
I only want to spend about three hours ~ inspecting the home .
Please tell me is it that important to know if the furnace is 16 years old or 20 years old they both are getting close to needing to be replaced .
Never has this been a discussion on any of my inspections.
I am not trying to be smart just would like a reason .
…Cookie
I have found that sometimes one’s “idea of the age” isn’t necessarily accurate because of other conditions. For example, I have found a one-year-old furnace that looked like it was twenty years old. It was in a very nice utility closet where the surfboards and wet suits were stored. The furnace was so rusted that I never would have thought that it was only a year old, and my Clients were quite surprised, as well.
I think that being able to tell one’s Clients exactly how old an appliance is certainly makes me look better in their eyes.
I spend as much time as needed inspecting the home. Back when I was a franchise, I tried to keep inspections under three hours, but I did it by simply taking more inspectors to the inspection.
Well, it’s similar to dating someone. When you’re 60, no one sees anything wrong with dating someone 56. When you’re 30, no one sees anything wrong with dating someone 26. However, when you’re 20, there are some problems with dating someone 16.
It works in reverse with appliance age. When it’s 20, there’s very little difference from the same appliance that is 16. However, when there’s a five-year warranty, there’s a big difference between something that is 5 and something that is 1.
Additionally, as with just about everything in life, there are cutoff points for certain things. If the manufacturer provides a one-year warranty, you’re out of luck if it breaks on the 368th day.
Insurance companies have those same cutoff points, so if a Client of mine has a problem with an appliance six months down the road, and the insurance company asks over the phone, “How old is it?”, to which my Client answers, “It’s new” or “It’s old” probably doesn’t help matters any.
To say that something is new or that something is old doesn’t necessarily tell the whole story. It’s all relative. Some would think that The Beatles are old, but every time I turn on the radio and listen to today’s crap, I find The Beatles new and refreshing.
So, to sum up, I like to know the age for two reasons:
(1) - It makes me look better in the eyes of my Clients, and
(2) - It helps them with their insurance, both in getting it initially since those insurance companies have cutoff points for insuring things, and down the road if they have a problem and need to file a claim.
I think I will stay doing it the way I do .
I see nothing to get excited about knowing the exact year of an appliance.
I do not know exactly how old the shingles are, just a guess estimate from past experience.
Works for me .
…Cookie
No surprise there.
Apples and oranges. Even then, though, many insurance companies here are requring a licensed roofing contractor to come out and tell them how old the shingles are. However, until I’m a licensed roofing contractor, or until the manufacturers start putting date codes on each shingle, I’ll leave that one alone.