OT: Looking fo HVAC/furnace advice.

[summilux]

We've got a 20 year old gas high efficiency furnace. It works fine, but maybe it's a bit loud if I were to complain about anything. It gets serviced every year and its on one of those service/warranty plans where the company fixes it if something goes wrong. Last week, something got stuck in the fan and the serviceman came over to fix it, which he did.

On the way out, he tells me that it's time to replace the furnace. He tells me that while the furnace is working fine, my fan is drawing 10A of current and that's far too much current relative to a modern furnace. He also said that heat exchangers only last about 20 years. Is replacement a good idea or is this some sales/snow job? We pay ~$200/year for the service/warranty package so a new furnace ($3-5K I think) needs to pay off with some gas/electricity savings. Heating season in Ottawa is October to early April.

Thanks for your advice.

[vqdriver]

don't know if it's a sales job or not. but twenty years is a long time to use something. a heater in winter is probably something you don't want to have to do, but rather something you schedule to have done on your own terms. if appliance death doesn't seem imminent and efficiency is the primary reason, it may serve you well to ride out the winter and have a few estimates done in the springtime. can't hurt.

[saab2000]

Google is also your friend here. I don't say that to be snarky. Had I not sold my condo in MI last summer I was thinking of putting in a new furnace myself. Googling 'Furnace lifespan' will get tons of results though hearing people's actual experience is, of course, very valuable too.

My brother replaced his a couple years ago after they started smelling gas in the house when they shouldn't. So they were in a bid of a bind and had to get it done rather quickly. His was pretty old (20-30 years) and he noticed that the new one heated up his house much more quickly and did it more quietly as well. I don't know about his bills, but I'm sure they went down.

At the very least 20 years is no longer very young and it's worth investigating.

FWIW, had I done my furnace I was likely to install a tankless water heater as well.

[45K10]

We replaced our 20 year old air handler / heat pump in our house in Florida a couple of years ago and it did make a noticeable difference in our electric (Hydro) bill. We went with an air handler that used a variable speed drive to lower the start-up current of the air handler fan motor.

Although I think electric power rates are a little lower in Canada than they are in the states so you may not see as much of a savings as we did.

My hydro bill in BC used to be around $80 bucks every two months compared to the average bill of $150 a month now in NC.

I was in Ottawa a couple of weeks ago man was it cold!

[summilux]

Google is also your friend here. I don't say that to be snarky.

I tried googling too, but basically what I found was that a gas furnace can last 10 years or it could last 40 years. And no info for what the electric draw for a new furnace is. We pay on average 10c kw/h here.

And yah, this has been the coldest winter that I remember, had about 3 weeks so far where temps have been -25oC.

[Ken Robb]

In most appliances what was "high efficiency" 20 years ago is now probably below average. Is there a time limit on your maintenance plan or are you guaranteed a working furnace as long as you continue to pay the annual fee. I would think at some point repair parts will no longer be available so maybe you would get a new furnace "free"?

Besides reducing the electric draw of the fan a new furnace would probably use less, gas, oil, electricity, corn cobs or whatever is your source of heat. I know you can get a new furnace that will be quieter than your old one.

[sales guy]

My family owned a construction/hvac company and most furnaces need replaced or updated between 20 and 30 years dependent on what type, usage, maintenance and manufacturer.

Gas furnaces, morpst of the problems are computer board related. There is the occasional gas pipe leaking, corrosion during the summer thing and of course lack of cleaning.

20 years and needing a new one? Not uncommon. For the reason he stated, kind of a sales/snow job. With a newer model, you may save about $15 a month depending on what you set your furnace at temp wise.

If it's working fine, keep it. I would suggest a different company service it though. Cause they make more money selling you a new furnace vs a service plan. The cost of a new furnace, their cost depending on manufacturer and how big it is, about $1500. The rest is labor and markup.

Keep the one you have and switch service companies.

[Peter P.]

Ask the repairman what the current draw on a new furnace fan is. Compare.

Regarding furnace noise: the output duct and return duct are isolated from the furnace by a flexible bellows. The furnace should be mounted on vibration isolation pads, on a concrete floor. Once those common install practices are met, any noise is coming from the blower motor or fan. The fan and blower will make noise because they're moving air, which can't be helped. Only if there are bad bearings in the blower or fan will there be excess noise.

The only thing left to reduce furnace noise is to install a sound barrier in the basement ceiling (expensive) and vibration damping material on the duct work (also expensive).

[josephr]

My family owned a construction/hvac company and most furnaces need replaced or updated between 20 and 30 years dependent on what type, usage, maintenance and manufacturer.

Gas furnaces, morpst of the problems are computer board related. There is the occasional gas pipe leaking, corrosion during the summer thing and of course lack of cleaning.

20 years and needing a new one? Not uncommon. For the reason he stated, kind of a sales/snow job. With a newer model, you may save about $15 a month depending on what you set your furnace at temp wise.

If it's working fine, keep it. I would suggest a different company service it though. Cause they make more money selling you a new furnace vs a service plan. The cost of a new furnace, their cost depending on manufacturer and how big it is, about $1500. The rest is labor and markup.

Keep the one you have and switch service companies.

+1 on this---just because something is old doesn't mean it needs to be replaced (even though my wife might say differently). Sounds to me like if you've gotten 20 years out of it, its probably a well-built, reliable unity. Get the max life out of and replace it when its dead. Just because you get a new one doesn't mean it won't break down either. I would go ahead and start doing some research and maybe get a couple of quotes from dealers. Simply because you'll be somewhat familiar with the market when the time comes.

SG-what are your thoughts on the ole 'cracked combustion chamber' thing...is that just a game? Always sounded suspicious to me..
Joe

[TBLS]

Agree with maintaining existing furnace until something significant goes wrong. I rode my 25 year old furnace through last winter and got bids over the summer as I expected it's next repair to be pricy. Having the bids in my pocket gave me some leverage in negotiating replacement vs. being a hostage in a house w/o heat.

[summilux]

Gas furnaces, morpst of the problems are computer board related. There is the occasional gas pipe leaking, corrosion during the summer thing and of course lack of cleaning.

SG, What you wrote had a good sense. They replaced the board two years ago, which they told me was a pricey repair. My spidey sense just tingled when they suggested we replace the furnace....

[sales guy]

SG, What you wrote had a good sense. They replaced the board two years ago, which they told me was a pricey repair. My spidey sense just tingled when they suggested we replace the furnace....


The boards are the most expensive and most common issue with any furnace. ESPECIALLY brand new ones. I can't tell you how many I had to replace when I worked for my families company. They are super cheaply made and are pretty simple design wise. Just cheap. And they get bounced around in transport. So I'm not surprised they go bad so easily.

[sales guy]

+1 on this---just because something is old doesn't mean it needs to be replaced (even though my wife might say differently). Sounds to me like if you've gotten 20 years out of it, its probably a well-built, reliable unity. Get the max life out of and replace it when its dead. Just because you get a new one doesn't mean it won't break down either. I would go ahead and start doing some research and maybe get a couple of quotes from dealers. Simply because you'll be somewhat familiar with the market when the time comes.

SG-what are your thoughts on the ole 'cracked combustion chamber' thing...is that just a game? Always sounded suspicious to me..
Joe


The combustion chamber can have issues. It's traditionally two stamped pieces of steel and they are welded or crimped together on the sides/ends. They are very thin and can leak. They are easily replaced if you are handy and do some research.

It's not a COMMON issues, boards are more the problem or having a dirty unit.

[malcolm]

I can give you my example whether it applicable or not who knows.
We had a service contract with a local company for our HVACs and had been with them over 10 years. The last few years every time they came out something had to be fixed usually for a couple hundred bucks so we were getting suspicious. The last visit before I fired them a guy came out for routine service and said there was something wrong and he could fix it for like $800 but he could not say how long it would last and it really should be replaced at 2-3k. He was really pressuring our nanny who was calling me at work wanting to know what to tell him. I basically said just leave it because the worse thing that could happen would be it broke and I had to replace it which is what he wanted to do anyway.

I have a friend that does HVAC work as part of his job and he came out hooked his gauges up and checked it out and said it was fine. That has been two years of trouble free service ago. We canceled our contract that day.

My buddy told me that when his company sent him to HVAC school all the guys there talked about fixing things that were not broken and selling units and parts that were not needed. Apparently it's fairly common for the tech to get a percentage of stuff he sells.

He may be right but I would check it out as much as I possibly could.

[Brian Smith]

Your financial analysis of whether or not you may prefer to replace your furnace may be strongly impacted by how long you want to enjoy the use of the new unit.
If you are leaving soon, almost no efficiency gain will play out to be financially beneficial, and few real estate transactions will properly account for the future benefit in any potential sale price.
Electricity may be inexpensive in Ottawa, though that should be a small piece of the heat system costs, and this year the gas may be relatively low-cost too. I think if you're looking for an absolute knock-out financial savings to recommend the upgrade, you may struggle to find it, depending on your future plans.
Contrary to some other opinions on the thread, I would actually HOPE that the tech inspecting an old system on a service call would have skin in the game if you follow his advice in getting a new system. Otherwise, why would a serviceman not simply recommend that you continue to service a wasteful system relative to the potential change? It may be hard to determine just HOW MUCH a new system should be incentivized, and there are likely to be other concerns than the homeowner's checkbook in those incentives. I just mean to say that your own decision may be impacted more by your own plans than the suspicions of potential technician renumeration.

[likebikes]

A new furnace will be much much more efficient. Choose the most efficient one for the best payback. Here in MA you can get lots of rebates/incentives for installing more/the most efficient furnaces etc. I would imagine in canada there might be a similar program?

[Tandem Rider]

Most HVAC mechanics are not "incentivized" by the company to sell parts. Everytime I have seen a company do this, they are headed out of business. It was just a last minute "hail Mary". Sometimes a company will pay a bonus for a referral or "lead" that becomes an equipment sale. I have never heard from anyone trustworthy of it being big enough to cover "date night". Remember, we are talking margin% smaller than your LBS gets on bicycles, not parts and accessories.

As to the OP's question, keeping it clean is most of the battle, dirt makes it run hotter and we all know what happens when equipment overheats. 20 year old high efficiency eqt is about 90 to 92%. Top shelf now is about 92 to 95%. How much is 3% of your heating fuel cost per year? Not your gas bill, that includes everything else, your heating fuel cost. How long for payback?

Residential furnaces are a stock item, kind of like $500 MTB's are at the LBS. Don't sweat the availability question.

My dad was a mechanical contractor from the late 50's until the early '80s, I have been in the service side of commercial and industrial since 1979.

[Pierre]

I'd run it into the ground assuming of course you have some relatives where you can camp out on the unfortunate day that it finally fails. Because guaranteed that it will not be a balmy -5degC when it does go out...

Besides, there's no way the marginal savings month over month are going to give you a reasonable payback that would justify doing this job now.

Just make sure you start doing some research ahead of time so that you are not at someone's mercy on d-day...

[billium]

We've got a 20 year old gas high efficiency furnace. It works fine, but maybe it's a bit loud if I were to complain about anything. It gets serviced every year and its on one of those service/warranty plans where the company fixes it if something goes wrong. Last week, something got stuck in the fan and the serviceman came over to fix it, which he did.

On the way out, he tells me that it's time to replace the furnace. He tells me that while the furnace is working fine, my fan is drawing 10A of current and that's far too much current relative to a modern furnace. He also said that heat exchangers only last about 20 years. Is replacement a good idea or is this some sales/snow job? We pay ~$200/year for the service/warranty package so a new furnace ($3-5K I think) needs to pay off with some gas/electricity savings. Heating season in Ottawa is October to early April.

Thanks for your advice.

Summilux:

I'm a GC, my $0.02 FWIW:

You're somewhere in the 70 to 80% of the normal useful life of a gas furnace, probably a little further on related to HE gas furnaces. Also, take into consideration the length and breadth of your Ottawa heating seasons. Regardless of how well your furnace is serviced, it does have a life expectancy. If you're leery about your tech's suggestion, have another HVAC contractor look it over.

From a return on investment standpoint, agree with others that you won't be able to justify a replacement based on projected savings.

At its age, I'd have the heat exchanger looked at specifically every year (assuming it's original to the furnace) as well as a CO-2 monitor on every floor.

Keep an eye out for local HVAC contractor sales/utility rebates/get at least three quotes/etc. Buying on your terms when it suits you (even if a year or two earlier than necessary) will save you a whole lot more than squeezing every last minute of life out of your current system and buying when you're in a pickle.