No chimney liner on the other bids was included?
Your chimney is an INTERIOR type. The venting tables for excluding a chimney liner under your circumstances are quite rigid.
YOU MUST MAKE SURE THAT YOUR CHIMNEY QUALIFIES
to be unlined or you will cause it to fall apart brick by brick.
OK, different parts of the country, but physics are the same.
With the 80% furnace in an unlined chimney it will sweat and cause severe damage.
I can only speak for my area(MI) the code requires a liner.
80% furnaces have been available since the early 1980s and the manufacturers were saying liners were needeed(according to the install manual)by the late 80s.
Several chimneys were reuined because there were no liners installed, and because of it became law that liners were required on every job from 1994 (in my state and many others that followed BOCA code) on.
Just because your town does not have a specific code requirement for the liner does not mean that you should forego it.
Check the install manual of any furnace company and you will see that it says they are required in cold climate.
That price you were quoted was high, I think.
Here in Mi we dont get that much for a liner.
But you will be the final decision maker. Check with the manfactuerer themselves and see what they say.
[Edited by curry on 09-30-2005 at 11:41 AM]
I hope this helps...
when i had one furnace replaced in my home I too had a lot of bids from different companies. I, like you, researched on the internet and this site to find the ideal replacement choice. I have an 94% efficient armstrong 2-stage variable speed furnace. I chose this because it had most of the features i desired. But the most important decision will be the dealer not the equipment. I found one who answered all my questions and had a squeeky clean BBB record. It looks like you already have a professional company help you with a previous problem and seems to be offering to do so again for you. I would ask about getting a more efficient furnace from them. I stress also getting a 10 yr. parts and labor warranty, sometimes with the more efficent furnaces the dealers toss in the warranty for free or as a promotion.
Everyone says that we DO have a liner in the chimney, but that you'd need a new one, especially if only the hot water heater is venting out the chimney. I can understand that. I guess I just don't get why you'd need one if both the furnace and the hot water heater are venting out the chimney, like they are now, with my old furnace.
I understand the point about a bird's nest blocking the chimney with fumes building up, etc. but isn't that the situation I'm in now anyway, and have been for 10 years? Wouldn't a bird's next block a new liner just as easily?
I guess what I'm hearing is that I should go with a 90+% efficient furnace. Any recommendations as to the size, given that everyone's quoting a range of BTU numbers?
Stay with the 75000 btu range,
I am sure if i did a manual j calc it would come close to 65000, but nobody you talked to had that range available.
Liner is a MUST unless somebody tells you they checked the venting charts and the demensions of your chimney jive with them.
Even with an inside chimney it is an extra margain of safety to have the liner.
The price just bothers me, but that maybe what they get for it in your area.
I wouldn't quote me to them, but check other companiy prices for a liner by it self.
If somebody is reputable but cheaper, havet the contractor you want do the furnace ect. and if he won't meet the other guys price on the liner , have the less exspensive company do it after.
Lots of good advise here, I just thougth I would add a few details:
1) The reason for the chimney liner is that the hot gases condense on the walls of the chimney. There are acids in the gases. This acid will literally eat the mortar from the joints between the bricks. It will not show up quickly, but I have seen many a 'crumbly chimney' from the furnace and/or WH venting through them (The chimney did not fall down, but it is really flakey and small parts come apart in your hands). Wonder what strong winds (like one of those hurricanes down south) would do to a crumbly chimney???
2) The person that suggested a matching coil for the 14 SEER condenser has a point (assuming it is a 14 SEER). Did the contractors go outside and copy the model/serial #'s off the condenser and then go inside and copy same off the existing furnace and coil? Did they explain the existing equipment to you, knowing the sizing and features (some folks would have to look that up unless they deal that line). The reason I am going here is that SEER efficiency more and more dependent on compatible (ideally matched) equipment.
3) I strongly agree with the high efficiency furnace. N-Gas will be going up a bunch this year (perhaps as much as 50% or more overlast year). Ask your contractors to show you some numbers for $$$ savings, and then research this yourself. Having said this, the variable speed furnaces are a nice touch. They do indeed help the SEER and heat efficiency, but they really make the home feel nice!!! Think on this one for a while: is is more important to save a few $$$ now, or to have the home feel really nice both winter and summer for the next 20 years???
4) I think this was said already, but let me stress this: Cheap equipment will perfrom adequatly if installed correctly. Top equipment will perform poorly if installed poorly. The installation is as important as the brand.
5) If I were recommending, I would go with either Trane or Rheem/RUUD. These are the brands I install, I am a bit biased. Note: Trane equipment is built like a tank, if that means anything to you.
Finally, and this is my opinion: Be careful to not be too much of a bean counter on this decision (bean counter=think only in $$$ terms). Sometimes folks that make major decisions this way end up being penny-wise and pound-foolish...
Best to you with your new system. Write a thread and let us know how it all turns out.
Your comfort, Your way, Everyday!
Your correct, if a bird builds a nest in your chimney in the summer, you'll get fumes also.
Instead of paying for a liner, why not get a 90+ furnace, and a direct vent water heater also.
A few points that were brought up;
Are modern furnaces venting that much different? YES, THEY ARE! The flue gases from an 80%, induced draft furnace want to condense and will condense as soon as they hit any cool portion of your chimney.
You say the chimney is lined, but with what? If it is a masonry chimney liner it will not heat up fast enough by the flue gases to prevent condensation.
You say that all of the chimney is surrounded by interior space. REALLY? No attic? No portion of the chimney sticking above the roof?......of course there is.
Older, less efficient furnaces are fine for colder weather applications because their flue gases are warm enough to heat a chimney and vent without condensing inside of the chimney.
A condensing furnace is great for colder climates because they are direct vented by means of pvc piping which if insulated can even be run through unconditioned spaces. Even if the flue gases do condensate, there is a means to drain that condensate.
Induced draft 80% furnaces are an absolute horror story in the making for colder climates. The flue gases are not hot enough to vent without severe considerations to prevent condensate issues but they are too hot for pvc venting.
...seek, and ye shall find;..
So always seek the Truth, not just what you want to believe to be true
Ecclesiastes 10:2 NIV
Soooo, now here's something interesting.
Called Contractor C, based on the fact that he was on time, thorough, and responsive with the bid. Told him that I was strongly considering going with him, and wanted to get the difference in price between his bid and a 94% efficient furnace. He asked why I was switching, and I told him that I had heard from several people in the know that in New England, I'd be better off and save more money in my monthly bills, by going to the higher efficiency.
He said, "Well, you're going to save more money, but it's going to take a lot of winters to make up the difference." I asked what the difference was, and he said $1,600 ($1,400 if I went with a higher-efficiency, but one stage furnace). The 94% has a lifetime warrenty on the exchanger, and 5 years on the parts (compared to 20 years / 5 years with the 80%). I asked him how much I could expect to save per month compared to the 80% furnace, and he said that without doing a full study, with my house, he'd guess between 5-10% per month on my bill.
Doing some 'back of the napkin' math, we're talking about EDIT TO FIX TYPO: _16_ years or so before the higher efficiency pays for itself, assuming that I'm running it pretty much straight for four months of the year and I'm truly getting 10% savings. Knock the difference to 5% and we're obviously doubling that. Worth it, espically given that more features may mean more other maintenance costs down the road? Hard for me to really say.
[Edited by jclancy on 10-03-2005 at 03:40 PM]
all of the figuring people do are at todays rates. what will gas costs be 5 yrs from now? always thought best to put in highest efficiency now and put savings in your pocket instead of utility companies for life of equip.
really not that much difference in controls from 80% to 94%. all have circuit boards and draft inducers. i feel that inducers on 90% furnaces last longer due to lower flue gas temps being conducted down motor shaft. get into 2 stage or v drive there is more to go wrong, but lennox controls have been reliable.
...and I would guess that the venting issues(cost)would cease being the headache here.
I hope so, good luck.
I would go with the 90%+ efficiency, it WILL pay for itself! Here in MN, they are predicting a 70% increase in natural gas prices this fall, and probably 40% throughout the heating season. That makes a BIG difference in the payback calcs! I'm already seeing "early winter" utility bills, and I haven't even turned the old furnace on yet!
I've gotten estimates, and of the two "finalists," both recommended the 90%+ efficiency furnaces. I figure the difference in my heating bills will be smaller than I originally thought (my current furnace is ancient, maybe 65%), but I will still save money, despite the jump in fuel costs. Some of my friends who went 80% are already kicking themselves, and heating season is just starting.
Thanks to all the great helpful people on this site! I would listen to the pros and take a good look at the high efficiency.
I'm in the hvac business in CT and I don't understand why any company would be so reluctent to sell you an 90% furnace over 80%.With fuel prices going nowhere but up a 90% will pay back much sooner,plus you get better venting,sealed combustion,make sure furnace is sealed combustion(2 pipe system 1 inlet 1 exhaust)takes air from ouside instead of indoor.If you have a decent budget for this go with a variable speed blower. It cost less to operate and with good air filtering can be operated continuesly for very little.Get the chimney lined but that price seems steep but maybe so is your roof.Make sure you are getting a flow through humidifier not a drum type with water sump that will just build up bacteria.I prefer April aire products.Get better filter (spacegard, AirBear,).Just my opinion
If it's possible, what would any of you estimate would be my monthly difference on my gas bill between an 80% and a 94%? Contractor C told me I'd see about an additional 5-10% savings a month with the 94%, compared to what the 80% would be. Is that what you all would guesstimate as well?
I'm paying, over the course of each winter - defined as November to April for my Quicken reports - anywhere from about $1,200 to about $1,500 in gas bills per winter over the past four years.
So, I'd be spending $1,600 more for this 94% furnace....even if you assume that gas is going up 50% this year and stays there (so, figuring my gas bill goes up to $2,100 for this winter and every one in the near future), I'm still talking about eight years to recoup the costs of this extra efficiency, and that's assuming that I'm getting a full 10% in savings over the 80% and that gas is really going to skyrocket in price by 50%. Am I doing the math wrong?
Don't get me wrong....I understand that if you invest in the higher efficiency, you save every month you use it. I have no doubt that's true. But if I'm only saving 5% or even 10% over what a _much_ cheaper 80% furnace can do, I'm having a hard time justifying the extra expenses in my mind, and the lackluster emphasis being placed on it by the contractors, even this guy when I say that I'm thinking of switching the bid to a 94%, isn't exactly winning me over to the idea. I'm really impacted by what this group on this forum is saying (NO ONE saying an 80% is the right move), but I'm also not seeing the value when I do the math of the actual bids I'm getting.
Is there a higher profit margin on 80%'s or something? What am I missing here?
[Edited by jclancy on 10-03-2005 at 11:24 PM]