New boiler

Taxer

Replacing 30 yr old gas boiler. Do I go with 82% eff or go with95% high effiency boiler. My plumber says high efficient boiler not worth extra costs. 3400 sq ft home in metro ny area. Current bill about 4000 annual heating costs. H.E. boiler is about 2k more, but he says more likely to break. He likes crown boilers. Please help I have no clue.

David Sutton_6

read, read ,read

search and read, there are always two sides to each coin, do your homework, talk to other heating pros. lots of info on this sight to help you make Your choice!

Xavier Breath

Rebates

Check with your utility company for rebates on high-efficient heating equipment.  Here in MA it's a sweet deal that can equate to thousands.

JStar

Boiler

I've found that the guys who talk bad about high efficiency equipment are the ones who don't understand, or don't know how to install them. Be cautious about anyone not willing to give you an option.

Steamhead

I'm assuming you're talking about gas-fired boilers

It is true that some 90%+ boilers have had issues. But more importantly, they cannot use a standard chimney to get rid of the combustion products. Therefore, you must have another way to exhaust them.



Typically, this is thru the sidewall of the house. But, depending on regulations in your area, you may not have enough clearance from windows and doors or enough height over your area's maximum recorded snow accumulation to vent thru the sidewall safely.



Another controversial area is that most of these units use PVC pipe for venting combustion products. The makers of PVC have not had their pipe approved for this purpose, and probably won't since it would open them up to liability when something goes wrong. So technically the use of PVC for combustion products doesn't meet Code, which requires combustion venting material to be properly listed (approved) for that purpose. And PVC is quite unforgiving of bad workmanship.



If a 90%+ unit is not an option, you're not limited to 82%. Look at the Burnham ES-2 series or one of the three-pass boilers with a power gas burner, all of which can hit 85% or better.

Steve Whitbeck

WHN

If you have cast iron radiators I would go with the Lochinvar WHN high eff. boiler.

I only sell the new fire tube boilers. Stay as far away from water tube boilers as you can. Giononi heat exchangers are old school.

I installed a WHN 155 in a guys house in 2011 - was over there last week and he told me his gas bills dropped 40% from the 10 year old 80% cast iron model.

I changed the boiler because he had two and the one for the addition needed to be replaced. Instead of replacing the old boiler I suggested replacing both with the WHN and piping the addition to the house boiler and zoning it.

Guy is REAL happy.

bob eck

New boiler

Take a look at the Prestige Solo or Prestige Excellence 95% AFUE gas boilers from Triangle Tube. Stainless steel heat exchanger uses outdoor reset control. Can be sidewall vented. If your contractor does not want to use PVC pipe to vent the boiler look at using Innoflue vent piping systems. Innoflue makes a chimney liner pipe kit that can be installed in your existing chimney if your chimney does not have a big offset. When this plastic chimney liner is installed in your chimney you can not vent anything else in that chimney like a gas water heater. Use one of Triangle Tube Smart stainless steel indirect water heaters with the Prestige boiler for domestic hot water. Lochinvar also has good high efficiency gas boilers. Sooner or later the cost for natural gas will also go up. I would go with high efficiency boiler with the outdoor reset control most of the heating season you will not be running your boiler at full output this boiler will be using just the right amount of energy to heat your house and not waist energy going up the chimney.

gennady

boiler choice

standard efficiency boilers are things of the past, as tubed tv and carburetor motors. you can add your plumber to this list.

Taxer

New boiler

So what percent would my bill go down using a 95% boiler vs an 82% boiler. My existing gas boiler is 30 yrs old. My utility company will give me a $750 rebate. Why do you have to redo your chimney. Is it more work to install a 95% boiler. I assume the iron cast boilers, sort of slide into place, where the h.e. boiler needs more plumbing work. My house has 4 zones. 3400 sq foot first floor with 2 zones and 2500 sq ft finished basement, but rarely use heat in basement.

gennady

ROI

what return do you have on your new car? new refrigerator? new granite counter top?

You do not have redo chimney. you will have to cap it and it reduces heat loss about 18%. not look at efficiency numbers. your current boiler efficiency is barely in low 60%. properly installed high efficiency boiler will give you comfort you never knew existed.

Taxer

New boiler

So going from 60 to 95 means I will cut my gas usage 35%. Is it that simple?

bob eck

New boiler

NO you will not save 35% but you will need to talk to a heating expert for a estimate on savings. Look at it this way. 82% boiler when there is a call for heat this boiler always comes on a full fire no matter how cold it is outside. With a condensing high efficiency boiler with outdoor reset this control knows what the outside temp is and will adjust the boiler firing rate according to the outside temp. On a day where the outside temp is at let's say 40* F the boiler might only be delivering 140* F water from the boiler to keep the house at 70* F as it gets colder like 0* F outside the control will see that and fire the boiler at high fire and it will be sending out 180* F water to keep the house at 70* F I hope this helps.

gennady

savings

you will save more than 35%, you will cut chimney losses, get more efficient modulating boiler which adapts to the house dynamic heat losses

Vinny_5

Taxer, this may help you in your decision:

While I am not close to being a heating professional, I can give you my first hand experience with my similar situation.  I am also in NY, but about 70 miles upstate of the metro area which gets a nice bit colder than the city.  Last August, I replaced a cast iron boiler which was rated at about 80% efficiency (which also had a Beckett heat manager fuel saving device installed on it).  I replaced it with a Lochinvar Knight WHN155 wall hung boiler and from a 12 month to 12 month comparison, I used 334 ccf's less this period compared to the last.  I went from 1,097 ccf's used in 2011 to 763 used in 2012 which is about a 30% savings from the 80% boiler, and the total cost to provide heat and hot water for my 2000 square foot home was $1,260 for the year. (You say you spent $4,000 to heat your 3,400 square foot home). Now I also must say that during the last heating season, it was mild compared to previous years, but last fall I also installed a 30,000 btu natural gas garage heater, which definately saw some good usage, so it is difficult to fully gauge the gas savings from the previous years.  What I do want to stress is that over time, it will pay for itself and then some in gas costs savings over a cast iron boiler. The outdoor reset and ability to modulate around the outdoor temperature really help in the fuel savings.  Also, my utility cut me a check for $770 for buying the boiler and outdoor reset. Hope this helps in your decision making.  Vinny.       

Steve Whitbeck

30 year old boiler

Even at 30 years old if it is in good condition it would not be down to 60% eff.

I would think high 60%.

Your saving depend on the type of heat radiators you have.

If you have in floor I would say that you would save as much as 50% or more.

If you have cast iron radiators and the new boiler is properly set up I have seen as much as 40 - 50%. 

If you have fin tube radiators I would expect +30% savings.

Again stay away from the water tube boilers. Expecially anything NEW.

Taxer

new boiler

So going from 80% to 95%, you used 30% less gas is impressive. I would think it would be like 15% savings. So what I am trying to figure out, is how much more effiecient is the 95% boiler over the 82% boiler? is it 13%, simple math or is it really more?  I dont mind spending more if I will get a long term savings, but not if it takes 15yrs.

SWEI

The math is not that simple

Due to standby losses and overshoot with a single firing rate boiler.  30% is pretty typical but it really depends.  If the old boiler was oversized and short cycling it could be more (possibly a lot more.)

Taxer

new boiler

so 30% savings between two brand new boilers one being 80% effeicient and the other 95%?

Taxer

new boiler

so 30% savings between two brand new boilers one being 80% effeicient and the other 95%?

Vinny_5

From my experience, yes.

That's what I have personally experienced with my copper fin hot water baseboard heating system. It will also depend on many other factors, which guys like Steve or Mark can explain in better detail. They also have extensive Lochinvar installation experience, and you can learn much from them.  

Good luck.