Finding furnace age

[jodil]

I am a new licensed inspector in ND. I am hoping soemone can tell me an eay way to look up furnace manufacture date by serial number. Is there a book to reference? A website perhaps? I have found alot of misc. information on the internet, but I know one of you experienced inspectors must have the anwer!

Thank you

[Les]

Jodi,

Welcome to the fray!

Just google up Prestons Guides and you will find them both new and used. Familiarize yourself with the series and company, because you should be using them often.

Maybe someone here has an extra set.

As a new inspector have you asked anyone in your area how they do it?

hope this helps!

[SonOfSwamp]

In my humble experience, most exterior A/C equipment that's less than 15 or so years old has the manufacturing date right there on the data plate -- day, month and year. The A/C data plate doesn't always match the furnace, but often it does.

Preston's Guide, I'm sure, works fine. But after a few weeks of looking at data plates, you should be able to figure out which numbers indicate the manufacturing date. For instance, if a furnace looks to be about 10 years old, and there's a pair of numbers printed on the data plate that indicate 96, 97, 98, well, the furnace was probably built in 96, 97 or 98.

Also, elements of industrial design -- colors, lettering, etc. -- are excellent clues to the age of the equipment.

Hint: While you're looking at the data plate, take out your cell phone, call the manufacturer on their toll-free line, read the tech the number on the data plate, and get the build date that way.

WJ

[Neal Lewis]

Maybe it's just me, but I would never make a phone call during an inspection to find out the age of a piece of equipment. There are too many other clues that would give me a year or pretty good idea of the age. I don't need to know the born-on date.

[jodil]

Thank you I will order the Prestons Guides. The furnances vary greatly in my area (rural ND.) Since I have started in Nov I have seen every age and kind of furnace that one can imagine. Yes, its true, people in ND still use oil, steam and corn pellets for heat.

[SonOfSwamp]

Originally posted by Neal Lewis

Maybe it's just me, but I would never make a phone call during an inspection to find out the age of a piece of equipment. There are too many other clues that would give me a year or pretty good idea of the age. I don't need to know the born-on date.

Me neither. I've wondered for years why HIs go to the trouble of tracking down the born-on date. An HI with a few years' experience can estimate the age of a furnace from a running horse.

But the brother asking the question said he was new to all this. A cell-phone call to the manufacturer would give him the answer he's looking for, not the answer you or I are looking for.

I've made dozens of calls to manufacturers. I've found out what unknown gizmos were; I got a guy a new Lennox furnace (because of a recall that would expire the day of the HI); I've found out whether or not equipment was installed to spec; and I've summoned muni codes bubbas out to re-inspect defects that they'd tagged as FINAL.

That said, I don't mind if HIs who aren't me never use a cell phone.

WJid="blue">

[Jim Katen]

Originally posted by jodil

I am a new licensed inspector in ND. I am hoping soemone can tell me an eay way to look up furnace manufacture date by serial number. Is there a book to reference? A website perhaps? I have found alot of misc. information on the internet, but I know one of you experienced inspectors must have the anwer!

Thank you

Jodi,

Right here on TIJ, click on the "Library" tab near the top of the page, then click on "Popular Files." The first document there is a handy furnace decoder. Print it out and carry it with you.

You'll occasionally run into a furnace that isn't mentioned by the chart. If you can't figure it out, post the make, model and serial number here and I'll bet you a dollar that someone will know how old it is.

- Jim Katen, Oregon

[hausdok]

Hi,

While I generally agree with Walter says about being able to recognize furnace age, there are a few that are pretty difficult to tell. Trane and Thermo-Pride are two; the Trane's because for over 20 years the color scheme or basic appearance has changed very, very little and the Thermo-Prides because they look the same now as they did 30 years ago and the only way to get the age is to call the manufacturer and give them the serial number.

The chart below should help. It's the chart that Jim talked about but I've recently updated it.

To download the newly revised chart, click here

ONE TEAM - ONE FIGHT!!!

Mike

[msteger]

Boilers are also a fun thing to decipher manufacture date. Most do not code their year of make in their serial numbers, although some of this info is within the unit. Of course, we are not taking the boiler apart, so we are not easily able to find this. Safe bet is to write down the serial number and brand and call the manufacturer. I routinely have to do this with Burnham, New Yorker, etc.

Furnaces are a heck of a lot easier once you know the various manufacturer keys after years of experience.

[Bain]

Slight drift, but I called Trane this morning to check whether a five-ton evaporator coil was appropriate for a four-ton heat-pump condenser, and the guy said it was okay if the system was appropriately ducted. I wanted to quiz him a little, and ask how they could work together if the condenser was properly charged, but he was impatient since I wasn't an HVAC guy.

I think the sizing issue has been covered ad nauseum, but to render it more frustrating, there don't appear to be any pat answers or formulas (I actually think formulae is correct, but it just sounds too pissy) to make certain the components are properly matched.

[hausdok]

I wouldn't worry about it.

Do you try to calculate whether the ducting for the hot air system is sized correctly? Probably not, that's not our function. We don't engineer the systems - we only evaluate their condition once they're in place. We do not have a duty to do any engineering calculations. I can understand writing it if it's something blatantly obvious, like a 3 inch duct feeding a huge room on a low-velocity system, but I wouldn't even waste my time trying to calculate something like that.

ONE TEAM - ONE FIGHT!!!

Mike

[Bain]

I don't Mike, but a guy was sued here a couple of years ago because a condenser was a ton larger than a coil and he didn't tell the buyers about it. So I always check the data plate to avoid the same problem.

I do see 4" ductwork in older houses that have had A/C added along the way. The 4" stuff--which carries about 25 cfm--is too small to properly circulate heavy, cool air, so I always write that up as a defect. Other than that, I don't comment on the number of ducts or their diameters.

[hausdok]

Hi,

Understood. I don't see a lot of AC systems. Seems to me I remember being taught that it's OK to oversize the coil for dehumidificatio purposes, though. Is that right?

OT - OF!!!

M.

[Bain]

Yep, but typically only by a 1/2 ton.

[jodil]

First thing... I'm a sister..not a brother

And I am one of only three inspectors in my town, so the Realtors here have a certain expectation of what my report will say (i.e. age of furnace.) It is expected here that your report will state the age and the remaining life left. I think its ridiculous for a HI to try and estimate the remaining life exp. as there are so many other factors in the equation, but until I run the other two out of town, I have to live up to the Realtors expectations!

Originally posted by hausdok

I wouldn't worry about it.

Do you try to calculate whether the ducting for the hot air system is sized correctly? Probably not, that's not our function. We don't engineer the systems - we only evaluate their condition once they're in place. We do not have a duty to do any engineering calculations. I can understand writing it if it's something blatantly obvious, like a 3 inch duct feeding a huge room on a low-velocity system, but I wouldn't even waste my time trying to calculate something like that.

ONE TEAM - ONE FIGHT!!!

Mike

[hausdok]

Originally posted by jodil

First thing... I'm a sister..not a brother

And I am one of only three inspectors in my town, so the Realtors here have a certain expectation of what my report will say (i.e. age of furnace.) It is expected here that your report will state the age and the remaining life left. I think its ridiculous for a HI to try and estimate the remaining life exp. as there are so many other factors in the equation, but until I run the other two out of town, I have to live up to the Realtors expectations!

Dang!

Now I gotta start minding my manners!

That's not too hard to do. Once you get used to how to discipher the data plates, you say something like:

The furnace was manufactured in XXXX. It's a gas furnace, so it has an expected service life of about 20 years, under perfect conditions. This furnace doesn't look like it's been well cared for, so there's no way to accurately predict how long it will last - it might last another 15 years or it might fail as I'm backing my car out of the driveway. Get it serviced by an HVAC pro annually and replace it when the pro tells you it time to do so.

OT - OF!!!

M.

[Jim Katen]

Originally posted by jodil

First thing... I'm a sister..not a brother

And I am one of only three inspectors in my town, so the Realtors here have a certain expectation of what my report will say (i.e. age of furnace.) It is expected here that your report will state the age and the remaining life left. I think its ridiculous for a HI to try and estimate the remaining life exp. as there are so many other factors in the equation, but until I run the other two out of town, I have to live up to the Realtors expectations!

Better yet, get together with the other two inspectors for lunch once a month or so. Figure out among the three of you how you're going to take control of your own businesses so that you three define your services instead of letting the realtors do it for you.

- Jim Katen, Oregon

[jodil]

I agree with you Jim! But unfortunatley they are both wusses, and they would never DARE stand up to the Realtors... (God forbid!)

Originally posted by Jim Katen

Originally posted by jodil

First thing... I'm a sister..not a brother

And I am one of only three inspectors in my town, so the Realtors here have a certain expectation of what my report will say (i.e. age of furnace.) It is expected here that your report will state the age and the remaining life left. I think its ridiculous for a HI to try and estimate the remaining life exp. as there are so many other factors in the equation, but until I run the other two out of town, I have to live up to the Realtors expectations!

Better yet, get together with the other two inspectors for lunch once a month or so. Figure out among the three of you how you're going to take control of your own businesses so that you three define your services instead of letting the realtors do it for you.

- Jim Katen, Oregon

[Jack Ahern]

If you plan on staying in this business, you have to decide whether you are the hammer or the nail. Being a reeeeltor's lackey will lead to an early and expensive dismissal from this business.

There are a few intelligent, strong lady HIs in my ' hood. It is lonely work.

Good luck in N.D. Get educated-take worthwhile advice-join a good national group-listen to your peers. Sift out good info and flush the rest. There are some excellent boards.

We are losing some old HIs due to the RE slowdown. Around here it is expensive to operate a HI business.[:-banghea[:-banghea

[SonOfSwamp]

Originally posted by jodil

First thing... I'm a sister..not a brother

And I am one of only three inspectors in my town, so the Realtors here have a certain expectation of what my report will say (i.e. age of furnace.) It is expected here that your report will state the age and the remaining life left.

I used to tell customers that everything that wears out on a house -- roof, HVAC, water heater, appliances, etc. -- will last about as long as a dog. People here don't mind homespun talk. And, everybody gets it.

Predicting service life is an RE lobbyist's dream. Heck, we don't know. Besides the dog thing, I told customers that HVAC equipment ought to last as long as the manufacturer's warranty, and anything after that is gravy.

WJid="blue">

[Les]

And I've been all worried about finding out I have sons and daughters out there and now I find I have a sister!

Does this mean I will finally get a birthday present from family? An extra present will let Randy N off the hook for this year.

I knew she was the other kind right off the bat; read her profile!

[hausdok]

I knew he couldn't resist for long,

Watch out for Les, Jodi, he's kind of a lady killer stalker.

OT - OF!!!

M.

[Bain]

Hey, Jodi. My sister--whose name is Jodi--lives in Denver and just got a job offer in McCall, ND. Is life good there, or way too bloody cold?

[Erby]

You've taken the best step just by being here and asking questions. Don't forget to read the archives. Lot's of good stuff there that'll never be repeated.

And the library offers some good reading material.

Be the hammer!

[Eric77]

I use the Technical Reference Guide by Carson Dunlop. I ordered it online directly from them. It's handy to use---small, spiral bound, with brand-to-manufacturer name references.

Eric