<p>Our heater is acting up. It's 18 year old Carrier. Is that old for a heater? Should we shop for a replacement?</p>
<p>I think a heater should last more than 18 years. But it is a boarder line case, we replaced a 25 year old one, because of efficiency. If the repair bill is too high, have it replaced with an exact size model, most of the work is in the duct.</p>
<p>We are on an annual contract. Repairs are taken care of by the contract. I didn't want it to die in the middle of the winter.</p>
<p>I assume then it's the company that has the service contract telling you it needs replacement ? If so get a second opinion. MY DH is in a related field so I know something about this. the other poster is correct that the work is in the duct but before replacing get a second opinion. The service contract world is all about up selling. The workers get a bonus if they come out for service and get you to do something that is not covered by the contract.</p>
<p>We had our (gas) furnace replaced at the same time we replaced the AC (which wasn't doing its job well, and the AC's and furnaces in our neighborhood of homes all built at the same time were starting to die like dominoes). The furnace was OKish, but it made sense to us to have it all done at once, with one unified system. Our system was about the same age as yours at the time. We chose to replace it before we had to deal with an epic fail during a harsh winter or heat wave.</p>
<p>^^ Be careful of the salesman. We bought a new house, and recieved many offers to vacum clean the duct at a rediculously low price. Called one in and the guy starts to point out all the problems in the duct and furnace, before he finish, its $400~500. I had a soft hart because it is a newly bought house. I should have said no to all his offers or not to call those guys at all. I was offered $150 to clean the duct from a HVAC guy before.</p>
<p>The company that installed/maintains ours with an annual contract has been trying to sell us a new system since it turned 12. We have had several repairs, ie. burner needed replacing. Most of the repairs have been minimal, things we could have fixed ourselves had we known what the problem was, but since it was gas we didn't want to take a chance. One was a vent plugged by a bird's nest. It is now 16 years old. I know it will probably have to be replaced at some point. Can any of the knowledgeable cc folks tell me if the system is much other than a pilot light, burner and fan with some duct work. If so, unless there's corrosion or some structural problem, leakage of CO2, etc. it shouldn't be that expensive to replace the parts rather than the whole.</p>
<p>The original HVACs in our neighborhood started failing after about ten years and they became expensive to repair. Basically they weren't designed for New England winters and they were inefficient and poor quality. We had ours replaced a few years later and it (combined with a roof replacement with high-efficiency vent) cut our heating and cooling bills in half. Even today, the most we spend on heating and cooling is still less than the worst of what we spent back in the 1980s.</p>
<p>My feeling is that the stuff in the 1990s was better made and of higher efficiency and better technology. Ours is about 17 years old and the only maintenance that we've done is to change the filters. It has never failed and never required a service call. So my feeling is that a gas heater shouldn't fail or give you problems after 18 years.</p>
<p>That's assuring. How long do they usually last then?</p>
<p>could you give us the symptoms or are you looking for approval for a new high efficiency unit before the tax incentives are forced to go away?</p>
<p>Our old 75-80%, cheapo unit lasted 20 years and still was cooking. DW is a efficiency nut. Bought a cheapo high efficiency.</p>
<p>IMO the cost of a unit is of course is the labor.
Other than that, they all have a blower(s), burner, heat exchanger, electronics and eh, eh, that's it. Question is how good is the burner and exchange metal and the motors?</p>
<p>No idea. But ours has shown no signs of problems. We never got a service contract on it. When I asked the installer what it needs for annual maintenance - he just looked at me as if I were strange - I guess they didn't need maintenance other than filters.</p>
<p>I looked around on the web for MTBF data but the manufacturers apparently don't put out this information. I did run into one post where a homeowner was replacing a 43-year-old furnace that had only had one minor repair over that time period. BTW, ours has worked out to something like $206/year (minus the gas company rebate and I don't recall the amount).</p>
<p>43 years! We had a motor replaced, some tube that was developing a dangerous crack, starters stop working every few years. We practically rebuilt(?) the entire unit over the course of years. Our repair contract is more than $300/year.</p>
<p>LP - No we are not looking for tax credit. I think the unit is efficient. It's from 1993 after the new regulations for efficiency were put in.</p>
<p>Igloo, just last month we replaced our 19 year old gas heater (and air conditioner). We have used the same HVAC company to service our heater/ac for over 20 years. They are very honest and very reliable. However, I started to notice that over the past 3 years, we were spending more and more $$$ on various repairs (about $1200). We also had a few system collapses during a heat wave. I knew it was only a matter of time before the heat went out during a frigid spell.</p>
<p>I asked the service people (whose opinion I really value) how long a system is supposed to last. Their response: 12-15 years for AC and 15-18 for heater. Since we were getting close to 19 years, we decided our luck was probably going to run out and we opted to replace the whole thing. We were at the point where we were putting too much $$$ into a dying system and we didn't want it to die during a most inconvenient time.</p>
<p>^^ You must have an el-cheapo furnace or the HVAC guy is doing a job on you. In the 14 years I owned the house in NJ since 1986, we never had an issue with the furnace and it was real old when we bought the house. We certainly had efficinecy issue, but not break downs. And believe me, we put a lot of use of that Furnace, nothing like we have been running in CA.</p>
<p>Our furnace dates back to the 1950s. Every time something goes wrong or it gets serviced I ask whether I should get it replaced, and every time I'm told there is life in the old girl. I'm sure a new one would take up half as much space and be quieter though! (It's steam and a boiler though, not gas and hot air.)</p>
<p>Like I said, I have a faith in the HVAC company. I never felt I he was doing a "job" on me. They have an excellent reputation in this area for precisely that reason. </p>
<p>Glad to hear your unit is still going strong after over 25 years. No, our unit was not el-cheapo, although I do think they no longer make them as well as they used to.</p>
<p>Thinking about it. Our gas unit had developed pinhole leaks-Steel heat exchangers and galvanized exhaust thus became dangerous. New unit has stainless exchanger and plastic exhaust.</p>
<p>Our current tankless water heater has galvanized exhaust. New building code is for stainless exhaust.</p>
<p>If you google "How long should a gas furnace last?" you will find that the lifetime of a properly maintained and installed gas furnace will range between 15 and 30 years, depending on quite a few factors, including the climate where you live. If repairs are becoming more frequent or expensive then it's time to replace it no matter what anyone else's experiences are.</p>
<p>When our house was built 13 years ago, contractor put in a Tempstar. What a POS. We didn't know any better. House is 3400 sf; later contractor said that furnace wouldn't have heated a 900 sf trailer, and he had never seen such a cheapy unit even in a trailer.</p>
<p>We replaced with a high-efficiency Amana at 8 years. H wanted a Trane or Carrier but our HVAC guy wasn't keen on it. Our LP has decreased 30%, but we've had a lot of service calls and misc. issues in 4 years. Furnace guy's reasoning is the new high efficiency furnaces have lots of sensors, etc. that shut things down. I'm not sure that should be true!! Plus, who cares if it's efficient if it requires service calls? Annoying and expensive.</p>
<p>My first 100 year old farmhouse had a 1970 low-boy furnace. They told me it was on its last leg from 1986-1997. I bought back the house last year-2011--SAME furnace. Old belt-driven monster, loud, but still chugging away. S lives there; not sure I'll replace it w/ high efficiency, and certainly not with an Amana!</p>
<p>Make sure you have a carbon monoxide detector near the furnace, gas fireplaces and throughout the house like a smoke detector. That is the biggest concern about a bad furnace.</p>
<p>Corrosion inside is usually from the central air - we were told to replace ours at 15 yrs because of that - when we got a second opinion, they said it will last another 4 years. It is six years past that. If it goes during the winter, our gas fireplace is enough to heat the house.</p>