Switch to High Efficiency Boiler? Here are the numbers...hard to justify?

spup345

Hi - Will try & keep as concise as possible while providing all info-
I am about to sign a contract to better insulate my 3000 sq. ft home plus heated finished basement (Air sealing & lots of foam from attic roof down to rim joist). I also need a new boiler, it's 33 years old, buzzes, and the circulating pump is rusty...all works, but on borrowed time. I'm in Rockland County, NY (across river from Westchester, about 30-40 mins northwest of Manhattan give or take).

Choices offered:
-$8800 (after $2k energy rebates) - TriangleTube Solo 110 (w/ outdoor reset) with 50-gallon Bradford White indirect (and my water would be treated for ~$100 to get it the way TriangleTube recommends, < 7 grains hardness, neutral PH)
-$3800 - Crown Aruba 4 Boiler (175k size) all-in & keep existing 40-gallon direct vent hot water heater

-->$330 annual projected energy savings for the high eff. vs existing system (takes into account insulation retrofit, via TREAT)...that is incremental to the annual savings I will get from the insulation retrofit, so it's isolated to the boiler upgrade alone.

Assuming I spend $1000 for a new hot water heater in the next 10 years, the Crown system solution moves up from $3800 to $4800. The high eff. solution is thus $4000 more. It would take around 12 years to breakeven ($4000 / $330).

Question for me is whether or not a 12-year breakeven is worth it (assuming the annual savings number is accurate)...here's how I view the pro/con's, do they look about right?

High eff. Pro:
-Lower carbon footprint
-Money in my pocket after 12 years
-Hot water will likely never run out
-Better internal air quality (slightly) due to way venting/combustion is done
-Good house selling point potentially?

High eff. Con:
-Repair costs may eat up energy savings (is this accurate? Or do the new low eff. boilers, like the Crown mentioned, potentially cost just as much over their life since they have much more electronic components nowadays?)
-May need to replace in 15 years as longevity is untested (Crown may last 30-40 years? Is that the current thinking?)
-If boiler is in need of repair, I have no hot water until it's fixed
-Possible longer lag time for repairs

To my untrained homeowner's eye, it feels like the scale is tipping in favor of the low efficiency system because the only REAL benefit (besides being good for humanity) of the high eff. system is that I MAY make money on it...but I can just as easily lose money on it and also be out of hot water if it needs to be repaired...(which may take a while...).

Am I missing anything or does this sum it up? Am I reading too many scare-tactics online about horrible high-eff. installs & fails? FYI - I've seen a system this contractor setup for another individual and it looks "clean" and that individual has had 1 year of use with it with no issues...

Thanks a ton! I'd like to sign this week, but need to decide on high vs. low eff. before I proceed.

SWEI

We don't discuss pricing here as a matter of policy.

How were the projected energy savings calculated? What were the projected number of therms for each design? What was the design day heat loss calculated at? The 110 is far too large for a well insulated 3,000 square foot house. Do not oversize your boiler.

Bad installation can kill any boiler, regardless of the type. Bad sizing can kill boilers. Either will kill efficiency before it kills the boiler. A properly sized, installed, and commissioned mod/con should last 20 years. Modern cast iron boilers are not built as heavily as the old iron monsters we see running at 50 years of age, but those old iron monsters have been costing their owners a LOT of money over the years that could easily have paid for an upgrade.

clammy

Not to shoot down the lower eff boiler job but to even the playing field is that crown install going to include make up air system and a inspection of your chimney and possible installation of a chimney liner .When those two items are added to the standard boiler it may well cost you more.There is a difference also in how each of these systems will operate the hi eff will modulate the burner to a lower firing rate to match what is need while the standard will run off it limits and on small zones it may just short cycle.I have a mod con in my home and am within 20 miles of your location my home is 1/3 the size of yours but,my highest gas bill was for this last month 105.00 bucks and that's the highest I ve ever had in 8 .5 years with my existing system. My average gas bill for off season hot water production is less then 20 bucks .That's with 2 adults and guests on the weekends .I didn t seat down and crunch the saving # when I did it but as the years pass I always see the savings in the fact that every gas bill I get usually always surprises me on how low it is .Summer average 20 bucks most of the winter between 40 to 60 bucks with last month being aall time hi but as you know it was aall time deep freeze in our area . PS You must make sure your unit is installed according to manafactures specs other wise you will have issues that is guarented.That unit requires primary secondary piping and that good piping pratices are followed .On another note before you sign on that line make sure your contractor has a digital combustion anylzer and digital manometer other wise he will not be able to properly test the combustion parameters of your equiptment .If they state that it is not needed then find another contractor.Those who do not own and use these tools are doing you .As for that price with out seeing it sounds like a bargain .Also ask them to do a heat lose for your home no sense in over sizing when that happens theres usually isn t to may happy faces .The reason for the heads up on combustion testing is that it s usually in our area it s quite thin and usually only performed by oil guys at the threat of gun fire and on gas I know of very very few ,i.m right across the border in Bergen that's how I know and used to work in rockland and orange in the past Peace and good luck clammy

Don_197

Also remember that the 12 year payback was most likely done using TODAYS energy prices...........which we all know go up a MINIMUM of every year..................with escalating fuel prices, the savings become more dramatic.............and may time occur more than twice as fast as projections. Also remember IF IT IS RADIANT heat, you may well be able to turn your thermostat down. We have been conditioned to use a thermostat as a gauge of comfort, and with radiant that just flat doesn't work. Star turning your thermostat down, one or two degrees at a time......find out where your REAL comfort level is (and it will change depending on solar gain, wind etc etc). When a radiant system is set up and controlled properly......they are about as efficient as you can get. the best systems control off a reset of some kind, and the water temperature is kept to its absolute lowest. Condensing boilers only condense with return water temps below 133 degrees......and from that point downward, they get more and more efficient as the return temperature drops.

Ironman

Please notice the yellow banner right above your post which forbids discussing pricing.

That being said, your data doesn't cosider all factors such as outdoor reset that doesn't show in the AFUE rating of the boiler. That can very easily save another 15-20%+. The mod/con has it; it can be added to a cast iron at additional cost and with less range and therefore less efficiency.

As SWEI a pointed out, you're missing the most important factor: the contractor. Both of those proposed boilers are probably twice as large as needed which will result in less efficiency and a shorter life span. If a contractor is not willing or able to do a heat loss calc with the job, then he's not competent even though he may posses good piping skills.

There's a current thread on the "Main Wall" about how to choose a good hydronic contractor. I highly suggest you take the time to read it.

Rich_49

I guess you have been in this home for a bit at this point , how long and what are your gas bills annually ?

Please tell us what the design heat load of the house is and what the design numbers are . We could probably give you a better idea of what the actual savings will be better than TREAT . Modeling is modeling and those numbers are never verified from actual performance , we have hard data from our designed systems to better calculate this than a model developed by a guy who graduated college with a degree in technology that knows nothing of how these systems function i nthe real world .
I'll bet the ECV (energy conservation value) we show will have a different result than TREAT .

Aaron_in_Maine

How come you need a 110 in the triangle tube with hot water and a 175 in the crown without hot water. Someone did not do a heat loss.

vaporvac

That's clear, @Aaron_in_Maine ! When contractors were pushing me towards a HW conversion, I recall they recommended the TTPrestige 110 and my house is at least twice the size.

unclejohn

I'm late to the show as usual but here's my 0.02 cents. Go with the hi eff. And if the same contractor gave you those prices go get another bid.

FranklinD

I'll add to this as a homeowner who went thru the decision process last year.

1) Educate yourself on the different types of boilers, the basics of how they work, the differences in how they work with different style emitters (radiant floor, cast iron radiators, baseboard, etc).

2) If your installer didn't do a heat loss calc as a first step, invite them to leave. This is a critical step for hot water heat.

3) If I could go back, I would find the extra $ and go for the smallest size Triangle Tube. My heat loss came out to 68000 btu/hr which, I found, is way on the high side for real life purposes.

I'd be curious as to why they have such a huge gap between the TT110 and a Crown 175. Makes no sense.

The TT will run long periods at low fire with the outdoor reset, better comfort, lower fuel use, less wear and tear.

The Crown is full on or off. No in between. What I refer to as a 'bang bang boiler'. Basically what I have as well. If not set up *just right* it can condense and eat itself or short cycle nonstop.

As others stated, it's all about the installation. The person HAS to know what they're doing. Remember: it's not just a boiler, it's a heating system. Ignoring everything but the boiler is a sure way to be miserable later.

Another thought: going with the Crown after doing all that sealing and insulating, you might have to provide combustion air from outside for the boiler. Just a thought.

spup345

Very helpful guys, and apologies on the pricing, I completely dropped the ball on that, won't happen again (I don't see a way to edit my post & remove or re-word that info unfortunately).

I'd like to respond to all the questions/comments raised in the chain so far to help clarify things, your comments are in bold and my incremental questions are in italics.

"is that crown install going to include make up air system and a inspection of your chimney and possible installation of a chimney liner"
-No mention of chimney inspection was made as it would basically be a simple swap of my existing boiler. Make-up air system wasn't mentioned, and I'm not sure what that is, but I do currently have a vent in my boiler room that cuts through my exterior wall to bring in "fresh" air if that's what you mean...(that would be foamed up if a high eff. was put in I believe)

"You must make sure your unit is installed according to manafactures specs other wise you will have issues that is guarented"
-Is the best way to do this by me reading the entire manual and compare/contrast with the install?

"That unit requires primary secondary piping and that good piping pratices are followed"
-Triangle said vertical exhaust is best to avoid flue gas recirculation, but I can't use my chimney since it has a separate fireplace flue...and my boiler room is under my livingroom so can't go vertical to roof either. Hopefully it can be worked around by setting the intake/exhaust "X" feet apart? Will this type of info be in the manuf. specs?

"On another note before you sign on that line make sure your contractor has a digital combustion anylzer and digital manometer other wise he will not be able to properly test the combustion parameters of your equiptment"
-Thanks, I will ask this question

"how long and what are your gas bills annually?"
-Been in house for 1.5yrs (2 winters though). Avg total bill = $535/mth; Avg. Gas portion = $271/mth (231ccf avg); Avg. Elec portion = $264/mth (1241kWh avg). Peak gas $636 (451 ccf - Feb
2014), this past Feb was $447 (545 ccf), guess energy prices dropped huh? Lowest gas was $43 (20 ccf) in the month after I moved in (Sep'14).

"How come you need a 110 in the triangle tube with hot water and a 175 in the crown without hot water. Someone did not do a heat loss."
-Low eff. guy was a separate contractor and was simply replacing my existing 180k BTU (heating capacity 141k) with a like-model...along with cleaning up the piping/replacing the valves. Very basic, no heat loss calc, no nothing...so yes, you are right on that part. However, to be fair, he wasn't factoring in my insulation retrofit at all...

"Please tell us what the design heat load of the house is and what the design numbers are ."
-High eff guy is a BPI-certified NYSerda compliant contractor, he input all my stats into TREAT and sent me a page called "Design Heating and Cooling Loads" - see attached screenshot for what was provided. However, for some reason he said he couldn't override the feet of baseboard, not sure why, but I actually have 260' of baseboard (I measured it myself)...that's about 2x what is in the calc sheet. Looks like the calc sheet is saying I need 80k Btu/hr based on the 123ft, that's why he went with the 110 since he knows I had twice as much baseboard.

"How were the projected energy savings calculated? What were the projected number of therms for each design? What was the design day heat loss calculated at? "
-The projected energy savings were calculated by using all the measurements of my house as performed by the NYSerda Energy Audit, along with the insulation/sealing that will be done. Then he gave me 3 calc's per my request, one showing the savings with no boiler change, one with a 85% boiler replacement, and one with the TriangleTube + indirect. The TriangleTube yielded $330 annual savings above & beyond the 85% boiler replacement.
-I don't know the projected number of therms or the design day heat loss information (but guessing I can find out).

"going with the Crown after doing all that sealing and insulating, you might have to provide combustion air from outside for the boiler."
-Interesting point...I called a HERS consultant today to find out what he'd charge for a heat loss calc (he wouldn't tell me on the phone since he said it depends on the workload involved) and we chatted a bit. He said a similar thing, that negative pressure may result from tightening the house, but since the boiler is in its own room downstairs and does have a vent which provides outside air into the room, I should be ok. However he said it will almost be like the boiler is operating in outdoor conditions because of that fact, which could lower the efficiency of the unit (A high eff. unit wouldn't have that problem). He personally has a high eff. Burnham w/ Burnham indirect (covered in a blanket)...he had to walk his contractor through how to set it up properly...(another scary & sad situation...)

Final note - I'm willing to measure every room in my house and provide basic stats (# of windows, feet of baseboard, etc..) if that will help get to a better, rough idea of how many BTU I really need?

Thanks again, this thread is invaluable to me already.

RJMCTAFO

Having all that baseboard with a tight house screams for a mod-con with outdoor reset. But not of the sizes you were quoted. A unit sized properly to the load will be condensing most likely the entire heating season if you have that much extra radiation.

A competent contractor with proper control and piping could hit this out of the park for you.

spup345

Quick sidenote - I did see first-hand several of the contractor's foam installs and 1 TriangleTube/indirect install in a diff. house (and I spoke at length with that homeowner in person) - looked clean, neat, professional and the homeowner has gotten through this past winter with no complaints about the setup.

Rich_49

There it is gents . The NYSERDA guy sized the boiler to the installed baseboard .
You my friend should be receiving a boiler that is capable of delivering 64,109 BTUh . Since the installed baseboard is 2xs required size you should probably be able to use <=130*F SWTs at design and lower the rest of the time . You can condense 100% of the time . Now the numbers are much easier to justify . You only require 246 BTU per foot , not the average 519 that the model calls for

http://www.slantfin.com/images/stories/Technical-Literature/ratings_fineline30_r.pdf

Contact me or one of the other guys to get you on the right track. Seems that no utility or program actually wants to build a good model that is accurate and does some good .
Please include town and /or zip code to determine HDD for your area . Your projected savings just went way up .

Zman

You never want size a boiler to the baseboard. The boiler should be sized to the heat loss.
The good news is that the abundant baseboard will allow you to run lower water temps and really let that mod/con do it's thing.
The guy sizing the 175 is not qualified.
The 110 is a bit oversized, how much would depend on how the house is zoned.

ww

It seems you want to insulate anyway..look into the best ways of doing that. You can then get this boiler serviced..change out the circulator pump...get the buzz noise whatever that is..a relay or something..fixed...clean out the boiler and tune it up. This shouldn't take too long to do..There are plenty of boilers way older than that.

I'd take care of the above and then do some more research regarding the boiler. The insulation can only help when and if you change the boiler in the future. I read all these claims on efficiency and wonder what they are all compared to in the final analysis.

Also...in time there may be alot more comments here for you to read and think about. Why make any hasty decisions?

ww

It seems you want to insulate anyway..look into the best ways of doing that. You can then get this boiler serviced..change out the circulator pump...get the buzz noise whatever that is..a relay or something..fixed...clean out the boiler and tune it up. This shouldn't take too long to do..There are plenty of boilers way older than that.

I'd take care of the above and then do some more research regarding the boiler. The insulation can only help when and if you change the boiler in the future. I read all these claims on efficiency and wonder what they are all compared to in the final analysis.

Also...in time there may be alot more comments here for you to read and think about. Why make any hasty decisions?

Ironman

I don't remember seeing if the 64k heat loss number was before or after the insulation. Either way, TT doesn't offer an 085, but Lochinvar does. The WHN has the same fire tube HX and comes in the 85k size. Several other manufacturers have reliable mod/cons in the 75-85k range: Bosch, Buderus, Dunkirk/Utica to name a few. I personally would not recommend any that use the Gianonni HX, but others may. It requires diligent maintenance.

spup345

It sounds like I may need a size (64k) that is different than what is offered by Triangle Tube (they have 60 or 110 I believe). I assume that the heat load calc spit out by TREAT included all my specs, including the insulation being recommended (at least I hope...), but unsure.

Is the safest bet here to basically get the insulation work done and THEN get a heating specialist contractor who is very familiar with mod/con installs & parameters to come by and make a recommendation?

What if I can't find someone who knows their stuff the way you guys do?

Separate question as well - There is a chance that by waiting the extra 1-2 months to get an appropriately sized mod/con in, that I lose out on the $2000 rebate from my energy company. My question is, will the incremental savings it sounds like I will get (per Rich's comment) from getting an appropriately sized mod/con, outweigh the loss of the $2k rebate? I guess my question is maybe for Rich....what magnitude of change did you mean by " Your projected savings just went way up"? Can pvt msg if not appropriate for the board, but % terms is fine too (not hard numbers).

Rich_49

Please Tell us your zip code and based on the numbers provided above an annual fuel usage estimate can be done from that .
Without a room by room heat loss that is accurate anything else is impossible , such as actual water temp required , real size needed , actual efficiency of boiler .
If the Hers rater comes for N/C and takes a look to get an idea of what he needs to charge , no harm done . Who did you contact and who did this TREAT calc already ?
With the zip code at least we can get accurate HDD for a fuel estimate that is usually accurate to within 100.00 or so in my experience .

The TREAT numbers would suggest that your house is 5,961 square feet , is this accurate or just another model anamoly . Based on the answer to that I would seriously consider another set of eyes on the job to perform this in a better way as opposed to a Honeywell , CSG , Utility approved modeling software . Get what I'm saying ?

spup345

Rich - I sent you a private message here which contains some names & my zip (thought that's what you wanted when you indicated I should contact you or someone else), but either way my zip is 10956.

The TREAT calc was done by the NYSerda contractor who really is a foam specialist and basically subcontracts any boiler-related work (but runs the data through the software to see if it qualifies for the program).

I can easily provide sq. footage of each room in my house, baseboard feet in each room, and number of windows in each room if that would get more accuracy, let me know.

The HERS guy would charge for a visit.

SWEI

Ironman said:

TT doesn't offer an 085, but Lochinvar does. The WHN has the same fire tube HX and comes in the 85k size.

To be specific, Lochinvar actually uses the older TT HX design which has a welded stainless condensate pan. TT's new HX design has a PP condensate pan that should be less sensitive to chloride leaching. Translation: PP or SS venting is likely even more important for the Lochinvar.

SWEI

spup345 said:

There is a chance that by waiting the extra 1-2 months to get an appropriately sized mod/con in, that I lose out on the $2000 rebate from my energy company.

You might want to read the fine print on that rebate program. Around here, it's the sales receipt for the boiler with a serial number that gets you the rebate (and not the installation per se.)

Rich_49

I received no Pm . dmcgrath40@comcast.net

Rich_49

Your HDD for the past 12 months are 6,551 at Westchester Airport . Based on the presented numbers and 94% AFUE (lower water temp) you should be using around 956 therms per year for all your NG needs assuming a family of four average household .

spup345

Thanks Rich - I basically wrote the same info here as I did in the private message to you so all good. I also may be working with a contractor I found from this website who is very knowledgeable and does a full-on heat loss calc (although charges 2 hours worth of fees for it, but small price to pay for an accurate sized boiler it sounds like)...just don't know how his overall installation price will compare (heat loss calc fees would apply to install if I use him).

What do I do with the therms info though?

As for the rebate, thanks SWEI but the rebate form unfortunately states: "Complete and sign the rebate application, attach a copy of the dated receipt/work order from your contractor that documents the installation, and mail to:"

Rich_49

Multiply it by your price per therm . Take total bill and divide by therms used for any month to come up with your cost per . Multiply 936 by that number . That will be around your total usage for the year . Divide by 12 to get an average per month or you could try to extraplolate month by month (pita) .

Rich_49

Good catch Hat . Was a bit tired , 956 would be correct .

spup345

Will try the calc's later, thanks. FYI - decided to remove the boiler from the NYSerda contract, just do the insulation and then get the right boiler from the right contractor for my home afterwards. Only time rush here is to get that energy rebate, $2k not chump change. Will keep you posted, thanks a ton, already helped me avoid a potentially poor decision.

Rich_49

Spup ,

You really should contact me . Phone stuff is free , nothing to lose , everything to gain . May be quite able to help you with your time crunch for rebates also .

spup345

Quick update. Had a full heat load calc done by a contractor on this forum who was recommended. In the end we decided against a high efficiency boiler and instead letting my existing boiler ride it out with the addition of a new outdoor reset control. Once the boiler goes, I'll replace with another standard version (but sized properly to the heat load calc this time!) unless the high efficiency ones come down in cost and/or become super reliable. For me, ease of quick repair and low cost of boiler and not worrying about losing hot water if boiler goes out, all factored into my decision. Ultimately you need to feel comfortable with whatever decision you make and this decision, after factoring in all variables (economics, reliability, etc), is what will help me sleep at night without worrying. Thanks for all the help guys, much appreciated.

jonny88

Is your current boiler able to take low return water temps or did the installer pipe in a bypass or some kind of boiler protection when installing the ODR.