I would only install a variable-speed blower. It will compensate (to a point) with less than perfect ductwork. There are few homes built with perfect ductwork.
There are too many advantages that the VS blower offers.
I've had two quotes so far, and it's significantly more expensive than I expected.
Both salesmen agree that my current 120K BTU furnace is way oversized based on their load calcs. They suggested an 80K BTU 2 stage furnace, and 3 ton compressor/condenser from their respective brands. I think both also suggest a 4 ton air handler, which is a step up over my current 3 ton model. One may have suggested a variable speed 5 ton. I was told there is an issue with small supply and returns. I indicated that I did not want any new ducting outside of the utility room, but I wanted everything *in* the utility room replaced, including having the plenums rebuilt.
The salesman I spoke with today seemed like a very straight forward guy. Much more technical and to the point with way less sales pitch, which was very nice. I have to say though, when he handed me the quote -- the sticker shock blew my mind a little. I had some trouble focusing on the details he was giving me after that.
The thing is, he listed both Carrier Infinity and Performance furnaces on the quote for price comparison, but says he'd refuse to install the Infinity because the variable speed motor doesn't suit my two level colonial home with the current duct structure, and the Performance is the same thing as the Inifinity just without the variable speed motor. He thinks that (and I hope I'm remembering this correctly) the T-stat would not kick it up to full speed often enough to keep the top level heated/conditioned properly.
As it is, we have significant stratification in temp between the two levels, and I must run the air handler always on a refresh cycle or sometimes even just straight 'on' to keep the two levels comfortable and similar in temp. In response to this, one salesman insists I need a variable speed that will always run at 30% minimum, non-stop; the other guy says I need a single speed ECM motor that just always outputs full power when it needs to run. These solutions seem mutually exclusive, and I'm not sure if both are valid answers to my particular problem.
Thanks for any opinions.
I would only install a variable-speed blower. It will compensate (to a point) with less than perfect ductwork. There are few homes built with perfect ductwork.
There are too many advantages that the VS blower offers.
Agreed with George2. A variable speed is nice step up from basic furnace which has fixed speed but can be adjusted but want work anything like a variable speed.
Most Variable speeds furnaces also come with 2 stage heating which is nice for more even temp throughout the home and allows you system to do more for less.
Variable speeds offer a great benfits for both your heating and cooling needs. I have never installed a variable speed air handler or furnace where the customer was unhappy with the performance.
One thing to bear in mind is variable speed is not a fix all. So ductwork sizing along with system sizing is very important to ensure the unit will work as designed. If ductwork is poor condition or not Sized properly the variable speed will want to ramp up to overcome high static.
I would look into the options and get more estimates as the main company you listed is steering you away from variable speed which he may have his reasons. Variable speed can help with hot and cold spots in the home, quiet operation, increased comfort etc.
Getting the right size furnace is essential to help even out the house temperatures. Smaller furnaces run longer cycles (should run "wide open" on the coldest nights) which will help even out the temperatures. Large furnaces shut off right about the time that the furthest registers are just starting to put out warm air. Up-sizing the blower won't fix the ductwork. Install equipment no larger than what your ductwork can deliver. Furnaces that cycle on high limit and compressors that burn out will be the result if your ductwork isn't up to the task.
A recipe for disaster. Sounds like your ducts are undersized now. Let the contractor tell you what you need instead of telling him what you want.I was told there is an issue with small supply and returns. I indicated that I did not want any new ducting outside of the utility room, but I wanted everything *in* the utility room replaced, including having the plenums rebuilt.
I completely get what you are saying. However, there is no way in hell we having the ceiling ripped out on our bottom floor to get the whole house re-ducted. That what it would take, as the truck runs laterally through the house, with branches coming off of it in both directs for the top floors, then branches running down the wall for the bottom floors. It would add thousands of dollars to an already expensive job. The existing sized system has done a decent, but not perfect job of heating & cooling the house so far, and that's with a very sloppy installation. I'm having the ducts replaced in the utility room primarily for appearance, because it looks like ****, and also it's not well matched up with ducts leaving the room. The bottom level return is blocked by about 30% because the ducts weren't lined up correctly when it was built. It's a very marginal cost with what I've been quoted to have it done, so to us it's entirely worth doing.
I have to be honest, I didn't expect the universal praise of the VS motor after the beating it's reputation took with this last salesman. Given that they both recommended similar sized systems, I don't think I'm pushing them on sizing.
What's a reasonable number of quotes? I was thinking 5-8 companies? There's no shortage of very large HVAC contractors in the area.
5-8 quotes? Really? 8? Why so many?
I always recommend 3 quotes, unless you called me out 1st. Then you only need 1 quote. .
Never go with the cheapest bid, you get what you pay for.
Do your research before you call for a quote.
Know what you want & why but be open to to what's recommended.
How long has he been in biz?
Does he service what he sells?
Does he have the proper licenses & insurance?
Is he willing to pull permits?
3 good bids & both of you be there.
Nothing worse that showing up for a bid- wife is there but husband is at work & he is the one who makes all the decisions. Or vice versa. Or they both are working & the 18 yr old kid is there to bid to.
A good bid will include a detailed description of work performed. It should be very detailed, very important.
It will include expected down payment & payment schedule.
His bid should include model numbers of all equipment & PDF's or literature hand-outs of all equipment.
Don't be afraid to ask questions.
Will he cover all floors w/ drop cloths?
What time do they start & finish?
How many days to complete?
How many people will be there?
Is someone on job in charge start to finish?
Referrals?
Block out all pricing from your thought to start.
Who made the most thorough presentation?
What does your gut tell you about each presentation?
9 times out of 10, your gut will be correct.
Who was the most professional?
Who do you trust the most- in your house- working on your system- around your family & pets?
What you have received from you statement "both recommended". Have a Manual J room by room load calculation done and then post it here. It is quite possible that the system size can be reduced to match the load and use a VS blower without failure.
In the interim post your location along with some details of the house and pictures of the mains in the utility room.
5-8 bids is crazy in my opion and leads to confusion. Think about this you get 5 companies that all give you 2 options for the system selection. That's 10 options that you have to choose from very confusion and where most customers make a mistake. Most tend then to just look at price as there only way to narrow down all the options for there homes.
I would also suggest 3 contractors come out. Tell them what you are looking for not the size but what you are trying to achive with the system. If you have a budget tell them what it is. All equipment manfactors have base, mid range all the way to top of the line. If you a dollar amount that you can't or don't want to exceed tell them. Contractors are not mind readers so by doing this you help narrow down the options per estimater and will make it easier on yourself.
If company that comes out will or should state why they should be choosen for the job. This should not include bad mouthing the other companies but instead showing and telling you why and how they would be the best choose for installing your new system. Ask for pics of previous jobs, referrals, manual j load cal (you shouldn't have to) as any good company will do this anyways and last what finacing options they have or rebates on equipment.
Again price is important but should not be your only deciding factor as a few more $$$ spent is nothing over the life of a system which is usual 15-20 years and even longer with good up keep of the system. Also a detailed estimate should include the scope of the work in detail, model #'s of equipment to be installed and finacing vs rebate options for the purchase.
I have been awarded more jobs not from being the cheapest guy out but by being the most professional company that listens to the customers concerns and offers solutions to correct or fix the problems/issues.
OK, following your advice, I accepted bids from the 4 contractors that I had scheduled at the time of your post, and didn't schedule any others. I was a bit disappointed with one of them, the guy stayed barely 15 minutes, had no promotional materials for what he was selling, and nothing in the way of suggestions for what I should buy. He kept asking me what brand and SEER I wanted. After the flaming I took on here, I was like "Just tell me what I need", trying not to push him in any particular direction. He said he'd get back to me in a couple days. I'm not even sure he took it seriously after that. However, he was the *only* contractor to pull out a measuring tape and actually measure all the rooms. His estimate ended up being the highest by far as well, including higher than another contractor that quoted the same system. Maybe he was pricing himself out of the job.
We were quoted for Amana, Carrier, Lennox, & Trane all 15.5-18 SEER. We settled on a 16 SEER Carrier Inifinity system. Personally, I like the way the Trane system looks far better. However, in the end we selected our contractor because he offered a 5 year labor warranty in addition to the standard 10/12 year parts warranties, and he didn't sell Trane. (Do I get points here for choosing service over brand?) His price was very competitive, and I've been happy with the essentially trouble free nature of our Carrier. You can't really blame it for breaking twice this year after running without a serious problem for 18 years, and that was with a truly low quality install and no yearly servicing.
After I had called him to arrange to sign the contract, he called me back just to tell me they were including an Infinity Touch at no extra charge. That was pretty damn cool, because we had planned on just keeping our existing T-stat.
Here is what we selected from the options he put together:
Condenser 24ANB636
Furnace 59TN6A
Coil CNPVP4821ALA