I am building a new 2 storey 2000 square foot house which will have an oil boiler hot water system using baseboard and cast iron rads. The oil furnace will have an indirect water tank attached also. I have been looking at the biasi B10, indirect water tank with outdoor temp sensor as well as the Buderus G115, indirect water tank and its outdoor temp sensor. Both systems boast that they are 30-40% more efficient than conventional oil boilers becuase of their 3 pass burner design and their regulator/temp sensors. I can get both setups around the same price but I'm not sure which one would be the most efficient? longest lasting? etc etc. Anyone know? or have experience with them?
Three-pass boilers are great, add Slant Fin, Viessmann, the Burnham MPO and some others to that list. Energy Kinetics makes a steel boiler that might merit attention--some love it, some hate it
ODR and an indirect will save you a bunch too.
First things first: You must do a heat loss for the new building and ensure the boiler is properly sized! Most boilers end up being two or three times larger than needed. The LONGER the boiler runs, the more efficient it is. A short cycling boiler is inefficient and wastes energy--kind of like flooring your car and breaking hard to keep at the speed limit!
The installation is as important as the boiler hardware. It must be sized and installed properly to work properly.
Also, consider that stack temps on the higher efficiency boilers will be typically under 400 degrees. They are often low enough where chimney and connector pipe condensation can occur. You may need to consider a stainless steel liner--I believe they are code in Maine for new installs?
I own a Biasi B4 and Tekmar 260 and I am fairly happy with it. It isn't the highest end boiler out there, but it seems to do the job. My oil tech measured it at 87% AFUE.
Since your building the house, you have the best opportunity right now for future savings by insulating to the hilt and choosing the best windows and doors you can afford.
Pete
Lifespan, efficiency, price... how would you prioritize them?
Some other solid 3 pass names with modern designs...
Burnham MPO
W-M Ultra Oil
Slant-Fin Eutectic (actually a DeDietrich)
Viessmann's Vitola if price isn't much of a factor
For the highest efficiency you could consider:
Peerless Ultra Oil (made in Europe by Hovel)
Monitor FCX
Did either contractor do a heatloss calculation? Neither boiler will work as well as the other if sized wrong.
The contractor is doing a heat loss for me. However, I did use Slant Fin's software for determining the heat loss. Assuming I filled in everything correct, I am coming up with a heat loss of 92,000.
I would prioritize them in 1st: efficiency 2nd: price 3rd: lifespan
What's the real difference between a Biasi, Buderus or Burham 3-pass? You should weigh payback versus cost when you are looking at a 2 or 3 percent savings. I don't think there will be a large difference between any 3-pass boiler that is properly sized, properly installed and setup correctly with an ODR unit. A Buderus with the Logamatic control is pretty pricy. Viessmann is right up there too. How long to recoup two or three thousand dollars when you're burning 800 gallons a year? Three percent of 3000 dollars is what? You may have to move into the condensing oil boilers to see any real savings, or even go over to a gas mod/con gas system. Are the condensing oil boilers a proven product in this country as of yet? I don't have the answers to that one.
I'm not trying to be smart, but those are the questions going through my mind when I think about your options. I don't have the answers, just trying to give you ideas to mull over. Hope they help.
peter
Can you do piping?
If so...
Get a good design and twist enough pipe (black iron's best) or solder well enough (boiler piping is much easier to solder since you can use 50/50 lead solder) to get your boiler room ready for a new boiler. The piping and layout needs to be very good calibre. Then the boiler is a changeout. Whoever bids the job isn't bidding unknowns and the labor is way down for them. Who knows (no pun), maybe that puts the Viessmann Vitola 200 into contention. That boiler requires no return water protection.
Minimal zones (TRVs ideally and a #916;P pump once they cost less than a grand - for now Grundfos 15-58s on the zones) controlled by a Taco 50?-EXP with the stats of your choice. The ODR for that zone controller is under $300 and the EXP adds about $80, but I really like the plug in controller it gives you. Choose a nice simple curve, don't worry about low return temps. Viessmann's controllers don't add enough value to pay for themselves and do you want to waste a week learning have the boiler superheat the water once a week so that you can keep the temp safely at 120° for the rest of the week.
It has a condensing secondary HX available in Europe that may arrive here once oil is all low sulphur.
Still, that would be my choice of boiler. I'd actually say going anything above the smallest model (72 MBH output) would be a tremendous waste and if you use that much hot water, you should use solar. A good installer wouldn't second guess you on the sizing if you would put it in writing that you are responsible for any errors in sizing (only fair for him right? and me I'll be hiding in Alaska) although he might advise you not to or that any recovery at design might be completely gone - which actually is perfect sizing. Still, when he goes to install it, seeing the nice piping would help get you the very best boiler at a more manageable price. If you can get some consensus here on the design, you'll know you're on the right track.
They make a great indirect too, but the price is just nuts... tops in efficiency and life - the horicell is an amazing small indirect but about twice the price or more of a tank-in-tank design which I'd rate second best. The horicell would go under the boiler and look amazing!!! The horicell in glass instead of stainless steel would probably still outlive you and take some of the equipment sting away.
May guess would be that if you had all the piping and controls ready for just a Viessmann combo the price would be about the same as what you'd pay for a Biasi or Buderus, but at a reduced efficiency. The extra would be what you spend in piping. Even just better controls and piping on your current boiler might make it a next year proposition for when some condensing oil boilers get proven.
Heating oil will be $5 a gallon... but nobody knows when yet.
Anyway, that'd be my advice...
WTF? 92K on a new 2000 square foot home?
Here's the specs on my 1975 brick backsplit that with a 0° design specs at 57K and is actually only about 37K based on logging a modcon boiler at and below design.
- brick backslplit, low pitched hip roof
- lower roof well insulated, upper roof probably as bad as lower roof was
- 3 uninsulated active recessed lamps in bathroom that would be well clear of insulation
- kitchen vaulted, poor insulation, 2 mediocre skylights
- upper launding valulted, 4 x 4 mediocre skylight
- windows new but half are marginal design (leaky - wanted casements and was sold sliders)
- front door very leaky, although house is tight
- walls insulated with crap 3 fibreglass
- basement is overinsulated compared to upper walls
- 4 levels @ 600 sf each plus 600 sf crawlspace
- crawlspace 54 clear space R5 1 XPS insulated
- crawlspace and lowest level on uninsulated slab
- low infiltration due to quality bricklaying offsets poor insulation
A new house and you can't do better than 92K? Fuel's going up... you should be able to get the heatloss down to 50K easy and way way less if you try hard enough.
Insulation's gonna go way up if fuel ever gets super expensive... I'd do it now.
you wound-up with, ya bought the WRONG house!
Perhaps you and Mike Holmes should get together and solve everyone`s problems?
Like I said, I did the heat loss assessment myself, and it was my first time so it could e way off- and really I'm saying it is a 2000 sq/ft house but I'm not thinking of the basement so it would be more. I live in a generally rural area and there aren't too many boiler options. These two just happen to be the onle two high efficient boilers in my area.
I'll question it like this then, which brand is generally known to be more efficient, buderus or biasi?
I would double check my numbers if I were you. My house was built in 1978 and is 2400 sq ft. I just ran the heat loss last weekend and it is 38k. My last house was built in 1919 and had no sidewall insulation. It has 10” in the attic ceiling and 3.5” in the floor. That home was 1800 sq ft. The heat loss was 70k. I feel you may have made a mistake in your calculation.
I'll question it like this then, which brand is generally known to be more efficient, buderus or biasi?
Piped identically, I'd doubt there there'd be much difference.
***** ***** ***** ***** *****
Olsen, sorry you didn't follow. My house is far from perfect for having minimal heatloss, but starting new with modern (not 1975) building techniques, should a 2000 sf home ever have 100 K heatloss? You be the judge, I think you like that roll.
and full of these insulation deficiencies.
Didn`t catch your date,,I stand corrected.
And no, I can`t see 100K heatloss at all in a new 2000sf house!
Olsen, exactly... in fact around here at least where building codes are far more what the builders want than what home buyers need, I would in fact bet money that a 2000 sg ft home with even an 60K heatloss would have to fail code in order to have a heatloss that great.
even at 60K that`s a lot.
Did you say you`re in Canada, where abouts?, I have relatives up there.
Olsen.
The Toronto area...
Sorry about the Mike Holmes crack,,,I hear he`s a stickler for perfection up there!
It is _very_ worthwhile to do an accurate heat loss for a variety of reasons.
However, if you are going to have an indirect water heater, then you are generally obligated to size the boiler to that, because typically it will require BTU input much higher than the heat loss.
Example: my heat loss is about 47k BTU/hr at design. I have a 40gal indirect that would like to see about 100k BTU for full rated performance. If I used a 50k boiler, my indirect would take forever and a day to recover.
So here's what I did, which might work for you, too. It's also fairly common practice. Nothing new here.
I split the difference and got an 84k output boiler. It's 30+k more than the house needs, and 15-20k less than the indirect wants. But, I put an anti-scald tempering valve on the indirect output to the house, and keep the tank at 140F. This basically makes the tank seem larger than it is because typical domestic supply temps are ~110F. By keeping the tank hot, the boiler will start to recover the indirect before the whole thing gets significantly below what the house hot supply temp is.
We have yet to have a hot water supply problem.
Now that you have an oversized boiler for the home's heat loss, the way to mitigate that is by using an outdoor reset control and associated piping strategy (what kind will depend on the boiler, and the planned supply temperatures over the range of outdoor temps/heat loss that you experience during heating season). The reset control keeps the supply temps low, and the piping strategy protects the boiler from low temperatures that produce damaging condensation, and maximizes the energy used when it does fire. This is one area where playing with the heat loss at various outdoor temps, and sizing the radiation to allow lower supply temps can really pay off.
Hi
I replaced a 40 y.o Utica boiler, a bullet proof boiler. I only bought one replacement burner and one replacement transformer in the 40 years.
Retired contractor here. 2 complete years with the Biasi with indirect H.W. heater. I purchased the Biasi only because the local guy here was thousands of dollars more with the Buderus boiler. I am very satisfied with the Biasi. My life long experience tells me to be cautious about efficiencies published by the manufacturer. The most important percentage is the efficiency after the installation is made! My guy used the Riello burner and Taco controls. I would say my unit is louder than the Buderus do in part to the buderus' cabinet design and insulation. Unless you're sleeping with the boiler the noise is not a factor. My wife pays the bills and says we are doing much better. We can't give an exact percentage because we have been away for several weeks during the winter compared to years back when we were working all the time. Oh, we put in a second oil filter .... boiler guy said Riello's run better ... I usually follow the advice of my subs. Last thing, I have a customer that put a Biasi in his second home in Maine the plumber bought 2 large hot water heater blankets and wrapped the Biasi with them. Guess what the boiler room temperature went down.... saving energy. You pro's would know better if this practice is advised. I like the Biasi, the system and installation ... all top notch.
I've had a Biasi and some of the toys, and we are very happy with it. Its a tad oversized but compared with my old pin boiler, we are approaching 30-40% savings, if I had discovered DIY sooner, I would have did the heat loss before I got the new boiler. Great forum.
Sid
I would pay attention to the Burnham MPO 3 pass boiler. They just introduced the IQ control on this product which has some nice features. It is very similar to the ES2 control.
The basic control has pump pre and post purge that you can enable and set a time period, One heat zone and one indirect zone with no additional external controls or relays. Two heat zones, if no IWH, with the addition of a SPST relay. Troubleshooting codes from the aquastat and primary control, read the cad cell ohms on the aquastat screen, boiler running hours and number of cycles.
If you chose pre-purge on the pump, given a heat demand, the boiler is above 140f the pump starts and the burner will not fire until the boiler gets below 140f. This helps avoid short cycling.
Also has plug in controls for LWCO and ODR to make wiring much easier. An optional display for troubleshooting and ease of set-up on control is available.
Check out Consumer Reports for September and you will see the ES2 and MPO-IQ are listed as Best Buys for 2010.
Tags: fuel, efficient, boilers, biasi, buderus, heat loss, indirect water, more efficient, Biasi Buderus, boiler that
