Time to break even going from 13seer to 16seer HP?

[Vivid]

Do you guys have a rough idea how long it takes to recoup the price difference between a 13seer single speed HP and a 16seer var speed HP?

[tpa-fl]

It's roughly 12-15 years to break even in Florida. Kinda like the difference between a 1.4 and a 1.6GHz computer. Not really noticeable.

[Vivid]

I was under the impression that seer rating was directly proportional to the amount of power used kind of like MPG for cars. So with that in mind 13seer to 16seer is a 25% increase in efficacy which I would have thought would make the payback time shorter than 12-15 years. At that long of a break even point it does not seem worth it to upgrade to 16seer.

I hope this does not break the rules so no figures will be used but what percentage increase is the cost of 16seer var speed HP VS 13seer single speed HP ?

[BigJon3475]

well if your bill is $100/month for just the HVAC system. You'll save about $25/month.

$25/month x 6 months. $150/year

$150/year x 10 years= $1500


It's directly proportionate to your actual bills now and the price difference your contractor gave you for the 13 SEER and 16 SEER systems.

[skippedover]

SEER is for cooling only units. The first word in the SEER acronym stand for Seasonal. A heat pump is NOT a seasonal product but rather a year 'round usage. Therefore the official designation for a heat pump is EER. The basic engineering definition of the NUMBER RATING for either SEER or EER is the number of BTU's the unit delivers for each 1 watt of electricity that's delivered to the unit. However that's not the whole story. The EER rating of a heat pump is generally about 15% LESS than the SEER rating. Furthermore if the indoor air handler/coil/blower is not matched to the outdoor unit/condenser, you may never achieve the sought after efficiency. In addition, many units come out of the box with a piston/fixed orifice as the pressure reducing device. All of the high efficiency units require the use of a TXV in order to achieve the desire results. When a TXV is installed, if the refrigerant charge is a little low or a little high, the TXV will still deliver the proper amount of refrigerant to the coil. This could save a service call when you need the system the most and certainly leads to better overall efficiency under variable load conditions. A properly selected and installed 14-SEER/EER unit will beat an improperly selected and/or installed 16-SEER/EER unit over both the short and long term. The actual efficiency improvement when going from 14 to 16, all else being equal is approximately 15%.

[be12c]

I agree, the efficiency of the system is dependent on installation. It is also tie to duct tightness, how the house is pressure balanced as well as overall building envelope tightness. As energy prices go up, it's nice to recommend a higher efficiency system, but unless everything is done correctly, you don't gain anything. It may be wiser to go with a lower SEER unit and make an investment into sealing ducts properly and pressure balancing the house. Little jumper ducts came make a big difference.

COP is the direct ratio of energy efficiency of a system as compared to electric heat which is considered 100% efficient. Typically, you gain another 100% for each 3.4 SEER rating increase in the system. At least in theory, before it's installed... To figure SEER, you need EER and then it's multiplied by a constant.

more info on SEER, COP: http://www.air-conditioner-selection.com/eer-seer-cop-air-conditioner-buying-guide.html

[Vivid]

Is a 16seer system harder to install than a 13seer unit? Or are the install principals, theories and amount of vents and returns the different? I ask this because the contractor mainly does 13 seer equipment and when we where talking he was not enthusiastic about the higher seer equ.

Also if the returns are so slim then why do many people spend the money on 16seer and even the 19seer when chances are you will need to replace the equipment before you break even...

I was all set on the 16seer heat pumps but right now I am asking myself why am I essentially wasting money?

[be12c]

Mechanically installing the system should not be any different between SEER ratings. It may just be outside of your contractor's comfort range. If your not planning on putting some effort into your duct system, then don't bother with the higher SEER because you won't see the payback. You'd be better off doing the 13 SEER and adding some weatherizing/duct sealing work, than just doing the higher SEER and ignoring the rest of the system. You'd end up with lower power bills anyway...

As far as the return goes, not all are like yours. What probably should of happened is a chase or wider wall should have been built to accommodate the system return requirements properly. Unfortunately, many architects don't think of such things until it's too late and then make do. Did you ever have a real load calculation done for your house and were the ducts sized right. That would probably give you an idea of what you should have, as apposed to, what you wound up with.

[Vivid]

as of right now I just have a wooden frame with house wrap, so I have the time to get it right or wrong, I do have a couple of large chases but there are some structural elements that are causing a bit of a challenge... I sent my plans up to an energy consultant who is running the loads, sizing and specking the equ (I requested he spec Rheem 16seer var speed HP, my contractor like Rheem)... He was also going to do a duct layout but without seeing all the structural elements it would be very hard to do on paper but he is going to put the CFM in and out for each room. I should get all of that back in the next few days...

But now I am still left asking myself if the equipment has a lifespan similar or shorter than the point of positive return then why do some many people do it? So many on here recommend it, to be honest that is why I was so gung-ho about specking it as 16seet var speed when both my GC and HVAC contractor are not pushing it.

[emcoasthvacr]

Had some disagreement, but I would go with a reliable 13 seer, which might provide better value.

It doesn't matter what you have if you have inefficient Ductboard & Flex ducting -- Doesn't make sense to have a modern system with draconian ductwork.

For galvinized ducts, your distribution losses (duct) will be approxiamently 13% for heating & 27% for cooling (based on engineering research from ASHRAE, the leading authority) -- Ductboard & Flex are much,much higher. Nobody on this site is qualified enough to dispute that.

[emcoasthvacr]

Had some disagreement, but I would go with a reliable 13 seer, which might provide overall better value.

It doesn't matter what you have if you have inefficient Ductboard & Flex ducting -- Doesn't make sense to have a modern system with draconian ductwork.

For galvinized ducts, your distribution losses will be 13% for cooling & 27% for heating (based on engineering research from ASHRAE, the leading authority) -- Ductboard & Flex are much,much higher. Nobody on this site is qualified enough to dispute that.

[Vivid]

I can say that the HVAC guy wanted to use insulated flex duct, I asked about using straight pipe but was told with my house it would be too hard because of the structural elements, complicated and expensive due to the fact that the pipe only come in 2' sections. The contractor is recommending 13 seer with flex duct... But I really wanted to var speed and efficiency of the 16seer because of how highly this board talked about those systems.

So Let me ask a different qu... if you had a choice of changing these two variable which would you do, 1. hard-pipe ducting with 13 seer equ 2. 16seer equipment with flex duxting

[Vivid]

My contractor likes Rheem so I am looking at the Rheem Prestige Series 16seer 2 stage units.

[ga-hvac-tech]

Here are a few thoughts:

The % of high end equipment that is sold is very small. Most folks, when they see the price, suffer a bad case of sticker shock... :eek: and back off.

I read that this is new construction? If so, you have a unique opportunity IMO to make absolutely sure your ductwork is properly sized and installed. If it were me, I would want as much metal ductwork as possible.

If it is all sized and installed and insulated properly, you are off to a good start.

Also, since this is new construction, you could start off with R-410 w/out a problem of running a new lineset later. IMO a good idea.

Lets visit a few HVAC terms here:

Variable Speed usually refers to the blower motor in the furnace (the part that move air around the inside). This is different from the A/C or a H/P.

Using a H/P in the Atlanta area will require some form of back-up heat, as the H/P will not handle the cold nights. Were you planning on a dual-fuel system (H/P and then gas furnace on the cold nights)?

My recommendation would be to use a RGPR furnace (80% 2-stage with variable speed blower), and a UPNL H/P (13 SEER R-410). With the VS furnace, you will end up with 13.5-14.0 SEER depending on the applications (assuming your ductwork is done correctly).

Add a nice T-stat and you will have a system that will be comfortable as well as economical to operate.

I would NOT skimp on insulation and other items that add to energy efficiency in the home.

Now if the home is too tight, you might need an ERV unit (fresh air exchange).

On, and one last thing: I would install media type air filters on each system. The cleaner air, less maintenance, and better air flow characteristics will be well worth the added cost.

As far as the 16 SEER goes: If you really want the best, and $$$ is not that important, then it would be an interesting engineering project. But I do not think it is cost effective in our Atlanta environment. Now if you were somewhere like Pheonix where it gets really HOT, maybe... But then, some folks just 'have' to have their toys... to each their own.

Personally; my home has the furnace mentioned above, with 13 SEER and a zone system (needed because of the house configuration). My energy costs are quite reasonable.

I am sure you have read this repeatedly, but let me say it one ore time: INSTALLATION is the MOST important part of an HVAC system. In new construction, quick and cheap is the norm. You may not like this, but one should expect to pay a hefty premium to get a first class installation in new construction (proper sizing, all metal ductwork, media filter, VS furnace, quality t-stat, etc).

I would put my $$$ in the duct system rather than the equipment (unless you want to get both).

Hope this helps.

BTW: Something you might find interesting: Rheem and RUUD are the same equipment with a different name label on them.

Just a side comment: I like the pic of your puppy.

[BigJon3475]

Here are a few thoughts:

The % of high end equipment that is sold is very small. Most folks, when they see the price, suffer a bad case of sticker shock... :eek: and back off.

I read that this is new construction? If so, you have a unique opportunity IMO to make absolutely sure your ductwork is properly sized and installed. If it were me, I would want as much metal ductwork as possible.

If it is all sized and installed and insulated properly, you are off to a good start.

Also, since this is new construction, you could start off with R-410 w/out a problem of running a new lineset later. IMO a good idea.

Lets visit a few HVAC terms here:

Variable Speed usually refers to the blower motor in the furnace (the part that move air around the inside). This is different from the A/C or a H/P.

Using a H/P in the Atlanta area will require some form of back-up heat, as the H/P will not handle the cold nights. Were you planning on a dual-fuel system (H/P and then gas furnace on the cold nights)?

My recommendation would be to use a RGPR furnace (80% 2-stage with variable speed blower), and a UPNL H/P (13 SEER R-410). With the VS furnace, you will end up with 13.5-14.0 SEER depending on the applications (assuming your ductwork is done correctly).

Add a nice T-stat and you will have a system that will be comfortable as well as economical to operate.

I would NOT skimp on insulation and other items that add to energy efficiency in the home.

Now if the home is too tight, you might need an ERV unit (fresh air exchange).

On, and one last thing: I would install media type air filters on each system. The cleaner air, less maintenance, and better air flow characteristics will be well worth the added cost.

As far as the 16 SEER goes: If you really want the best, and $$$ is not that important, then it would be an interesting engineering project. But I do not think it is cost effective in our Atlanta environment. Now if you were somewhere like Pheonix where it gets really HOT, maybe... But then, some folks just 'have' to have their toys... to each their own.

Personally; my home has the furnace mentioned above, with 13 SEER and a zone system (needed because of the house configuration). My energy costs are quite reasonable.

I am sure you have read this repeatedly, but let me say it one ore time: INSTALLATION is the MOST important part of an HVAC system. In new construction, quick and cheap is the norm. You may not like this, but one should expect to pay a hefty premium to get a first class installation in new construction (proper sizing, all metal ductwork, media filter, VS furnace, quality t-stat, etc).

I would put my $$$ in the duct system rather than the equipment (unless you want to get both).

Hope this helps.

BTW: Something you might find interesting: Rheem and RUUD are the same equipment with a different name label on them.

Just a side comment: I like the pic of your puppy.


I think you just about nailed that perfectly IMO for whatever thats worth. Take all advantages while your in new construction as later will be expensive.

[Vivid]

GA-HVAC-Tech,

thanks for your lenghtly reply. let me try to ans some of your points...

Yes this is a new construction project and I am scared to death of getting it wrong. I am having the main HVAC specialists from Guaranteed Watt Saver doing my load cals right now. He is also going to spec and size the equ, but I think I am going to call him tomorrow and change it to 13 seer equ from the 16seer I requested. He is also doing a cfm in and out for each room. He offered to do a duct layout but I opted not to because my house would be too hard to do without seeing it on site.

My GC has used this HVAC company for all his homes including his own and has never had a problem, my GC is a very stand up guy and have faith in him and his subs. I met the HVAC contractor on site and he talked about all the things I see this board talking about as problem areas. The HVAC contractor recommends using some heat strips for extra heat, he said in ATL I would only need them for a handful of days and it was not worth doing anything more. He also recommends 13 seer equ with a var speed blower, with media filters and a touch screen T-stat, the only downside is he does not advise hard-ducts.

As for other energy saving items, I am using spray foam insulation and tinted glass.

Would you mind if I emailed you with the name of the HVAC company to see if you have heard anything about them?

thanks again

[ga-hvac-tech]

GA-HVAC-Tech,

thanks for your lenghtly reply. let me try to ans some of your points...

Yes this is a new construction project and I am scared to death of getting it wrong. I am having the main HVAC specialists from Guaranteed Watt Saver doing my load cals right now. He is also going to spec and size the equ, but I think I am going to call him tomorrow and change it to 13 seer equ from the 16seer I requested. He is also doing a cfm in and out for each room. He offered to do a duct layout but I opted not to because my house would be too hard to do without seeing it on site.

My GC has used this HVAC company for all his homes including his own and has never had a problem, my GC is a very stand up guy and have faith in him and his subs. I met the HVAC contractor on site and he talked about all the things I see this board talking about as problem areas. The HVAC contractor recommends using some heat strips for extra heat, he said in ATL I would only need them for a handful of days and it was not worth doing anything more. He also recommends 13 seer equ with a var speed blower, with media filters and a touch screen T-stat, the only downside is he does not advise hard-ducts.

As for other energy saving items, I am using spray foam insulation and tinted glass.

Would you mind if I emailed you with the name of the HVAC company to see if you have heard anything about them?

thanks again

Sure, Email me. You and I can communicate a little more freely off-line.

It is late, ZZZ time.

[BigJon3475]

Just a thought but post a thread with your city in mind on here I know several GA. folks that could probably give you some good ideas for what type of system you will need.

[emcoasthvacr]

It would be better if you had a metal plenum and trunk line -- if the runs are short, flex ain't gonna hurt on the branches. And like you said, metal is a PITA to run when you have to navigate the structural integrity of a home.

I would think the 13 seer would give the best value, especially with variable speed, but we might be pitching pennies between the two.

Man, a Heat Pump with auxillary gas heat would rock if installed properly -- I wish I had one...lol.

In north suburbs of Atlanta, it's all AC & gas (homes were built around 1998); In Florida, I have to live with a HP & strip heat run on electric.



I can say that the HVAC guy wanted to use insulated flex duct, I asked about using straight pipe but was told with my house it would be too hard because of the structural elements, complicated and expensive due to the fact that the pipe only come in 2' sections. The contractor is recommending 13 seer with flex duct... But I really wanted to var speed and efficiency of the 16seer because of how highly this board talked about those systems.

So Let me ask a different qu... if you had a choice of changing these two variable which would you do, 1. hard-pipe ducting with 13 seer equ 2. 16seer equipment with flex duxting

[dallasbill]

RE: what GA-HVAC-Tech said "My recommendation would be to use a RGPR furnace (80% 2-stage with variable speed blower), and a UPNL H/P (13 SEER R-410). With the VS furnace, you will end up with 13.5-14.0 SEER depending on the applications (assuming your ductwork is done correctly). "

That's exactly what we went with 2 years ago, with Carrier Infinity and their control (no HP here). Spent the money saved on spray foaming all flex duct connections and boots, a lot of the exposed flex duct along one area of the attic floor, and the sides of the coil box in the attic. The only thing I would have done differently in restrospect is gone 2-stage on the outdoor condensor. But, we really don't notice it anyway, as our bills are so low and comfort so high.

[Mstrav]

when it comes to energy savings, you have to "consume" to save. having a $25 savings for a hundred seems small. If you save $25 per hundred and your electric bill was $400 you would get your money back quicker. As stated get a variable speed blower, you might as well go 410a refrigerant, 14 seer condensor and a huge coil to achieve as high seer as you can. 2-stage is great on the heat side, and do not buy a $40 dollar thermostat to control it!!! get one with good set back and fan timers so you can set it up nice. Also as noted make sure your attic is vented properly and you over insulate and seal your duct. make sure all the register cans are insulated in addition to any return air cans. pooky every joint, collar and seam!!

good luck, matt