new commercial boiler needed.

DavidMarasow

i have 3 large multifamily properties about 120-80 units in each, that need new water boiler that can provide heat and hot water....about 2 million BTU.


i'm thinking of putting in new condensing high efficiency boilers. what brand would you install and why?
i have options for a few Viessmanns VITODENS 200-W, or the Lochinvar Crest boilers. or maybe a Well McClain....
i need the most reliable device....

EBEBRATT-Ed

Looks like a Smith 28 with a PowerFlame gas burner. That's not a bad set up. Condensing boiler will be $$$. I would check for gas company rebates in your location. You can go condensing or put in something similar to what you have.

I would do a heat loss calculation first to make sure you get the right size boiler.

Look for a quality contractor on this site under "find a contractor"

What's your location

nicholas bonham-carter

Are the present boilers having problems, or are you just being proactive? are the buildings using a combined or separated heating system? Is the temperature even throughout now?
Remember that the new condensing boilers will only achieve their maximum efficiency if the amount of radiators permit a lower water temperature. the modulation feature does have some benefits, but that may not outweigh the increased need for regular maintenance.
An expert hydronics contractor can walk you through the choices, and he will perform a heat loss survey.
What is your location?--NBC

Paul Pollets

Viessmann Vitocrossal would be my choice...https://www.viessmann.ca/en/commercial/gas-boilers/gas-condensing-boiler/vitocrossal_200-cm2.html

Tinman

Where are the buildings located?

Mike_Sheppard

I personally prefer the Lochinvar condensing products when it comes to heating. They have great support, are easy to work on, and work great.

But it’s hard to argue against a standard efficiency set up like you have already. It’s cheaper, requires less maintenance, and doesn’t break as much. If you have great maintainance for the property and make sure to do all the factory required maintenance to the boilers, and can run the heating loop at lower temperatures on a reset, it could be a worthy investment.

If maintenance will not be great, don’t do it. If you can’t run condensing temps a majority of the time, don’t do it.

When it comes to condensing, the three criteria I focus on is application, installition, and maintenance. A condensing boiler used in the wrong application, installed wrong, or poorly maintained is a waste of money.

nicholas bonham-carter

I wonder if the cost per BTU output goes up or down when you compare the installed cost of one large (2 mil) conventional boiler with several smaller ones connected together. There must be diminishing returns, especially if the boiler room is in a difficult location.
Several boilers would give some measure of redundancy, and not all would have to fire in the summer for hot water.
If there is room for only one large one, then the Peerless 211A has the Mod-u-Pac hi-lo-hi gas train which would reduce costs for hot water generation.
An experienced contractor would also be able to tell if the lifespan had been compromised by an incorrect installation.
It seems like we have lost our tail gunner on this post!—NBC

JohnNY

My go-to manufacturers are Lochinvar and Weil-McLain equally.

GBart

Having multiple staged smaller boilers is the way to go, Weil McLain or Lochinvar are known greats, with staged smaller boilers you might save close to 50% of your fuel bill.

SuperJ

GBart said:

Having multiple staged smaller boilers is the way to go, Weil McLain or Lochinvar are known greats, with staged smaller boilers you might save close to 50% of your fuel bill.

I agree, smaller boilers work much better most of the year when you only need a fraction of 2 million BTU's.
I like the IBC SL 40-399 G3 boiler, five of them would be a sweet setup (50:1 turn down). Comes with BACnet/IP standard, and capable controls including cascading, which is nice if you have a control system.

You also have better redundancy than if you had 2 big boilers, and if something better comes along in the future you can replace it 1 boiler at a time.

The Viessmann Vitocrossal is interesting, it's basically 3 boilers in a box (in the big commercial models). You can pipe it variable primary only to make retrofits easy.

The Steam Whisperer

If you already have modulating burners and outdoor reset on that type of boiler, you probably are not going to see significant savings with condensing boilers. Mod burners and outdoor reset, properly set up, will probably get that existing boiler up near 85 to 87% efficient. There seems to be considerable consensus that generally about 2/3 of the fuel savings typically seen from the installation of mod con boilers comes from the modulation part, and only 1/3 from the condensing part. The substantial savings achieved from installing simple on/off stage fired smaller individual boilers really drives that point home too. If you want some back up capacity or increased simplicity, some stage fired atmospherics can operate quite efficiently too, or you can bump up efficiency with smaller stage fired power burners. A general rule of thumb is to invest in boosting efficiency for only 60% of the buildings peak load ( the base load) since the building will be at that load or less for 90% of the heating season. Any heating plant capacity over 60% of peak load will only be used a few days a year, so it is an extremely poor investment to install high efficiency equipment for this load. Using 2 more efficient models for baseload ( maybe power burners) and then the rest with an atmospheric would give you very high efficiency, but eliminates the complexity and shorter life of mod cons.

Tinman

Mod cons are not complex. Nor does anyone have a firm grasp on what the life expectancy of the newer, high end, well maintained units are. Customers need to be more than just informed on the need for annual maintenance. They should be told it's a must.

nicholas bonham-carter

I think that people are afraid of all the proprietary parts in mod cons. When the inducer fan, or computer board fails on some Friday afternoon in January, and it’s -10 outside, will the service tech have one on his truck?
Computer parts are often rated by mean time to failure, but is there such a designation for boiler parts, (or for those who service/install them)?—NBC

bob eck

Find a good professional heating contractor.
Get a heat loss done on the building. The current boiler could be over sized.
I would get bid on one large cast iron boiler.
Two - four smaller cast iron boilers.
Two or three condensing commercial boilers
Three to five condensing 399,000 BTU boilers.
Use indirect water heaters for domestic hot water.

Check into Caleffi BTU meters and you might be able to bill each apartment for the amount of BTU used for heat and hot water.

GBart

nicholas bonham-carter said:

I think that people are afraid of all the proprietary parts in mod cons. When the inducer fan, or computer board fails on some Friday afternoon in January, and it’s -10 outside, will the service tech have one on his truck?
Computer parts are often rated by mean time to failure, but is there such a designation for boiler parts, (or for those who service/install them)?—NBC

with a bank of 10-20 it wouldn't matter,a smart sales approach would be to off one set of replacement parts to seal the deal

EBEBRATT-Ed

@nicholas bonham-carter

Parts availability for any of the Viessmanns etc who have had to fly an oil pump for a Weishaupt burner in from France.....there wasn't one in the state. Metric flexable oil lines flown in from Italy The residential boilers are just as bad

The Steam Whisperer

Yes, I agree on the issue of proprietary parts. We installed Triangle Tube Mod cons when they first hit the US market ( they have been available for about 25 years now oveseas, I believe), but as we have seen supply houses no longer stock replacement components, dealing with a lot of proprietary components is bad for the customer and us. We even purchased the repair parts package, but as the number of models grew, this became extremely costly, particularly when replacement parts you have on hand are obsoleted by software updates and other design changes. It was one of the driving factors of why we decided to focus almost completely on steam... Most replacement components are not proprietary

Tinman

I was primarily a Lochinvar Knight dealer and I stocked the parts for all of the ones I sold. If you're going to commit to the mod con market, ya gotta go all in. I thought of it as my responsibility to stock just about everything but the HX.

The Steam Whisperer

Yes, Steve hit it on the head, if you install modcons you've got to go all in and carry a complete inventory.

tim smith

We have done numerous multi boiler, multi family jobs. Our go to boilers are the whn, Khn Lochinvars. (Now Whb, Khb) knight boilers. I have been totally impressed over last 8 yrs with no main part failures. My favorite in larger loads would be multiples of 399s. You would have 40 to 50 to one turn down. The parts I feel are less costly in the smaller mass produced boiler. Buy a parts kit for the 399s and have on site when you get boilers. A lot of the year you will only need possibly one boiler. Depending on type of radiation, you may be able to have your lowest water temp at 90 with a high at 150 or so. This can be calculated by your contractor. All dependent on radiation type, size of radiators and output to load of spaces.
Good luck
Tim

mikeg2015

Could put in a mix of standard efficiency boilers at a lower cost and add a condensing swing boiler in mild weather and for DHW (which will condense) with indirect tanks.

Definitely figure out water temperatures first. IF return is over 130F, won’t get more than 88% out of a condensing boiler.

I really like the Crest boilers. Had a FTXL. Had all the controls and DHW priority and water temp built in. Could run a variable speed circulator as well. Just needed ot add remote temp sensors for the DHW tank and secondary loop.

Henry

Have you done an analysis of the heat loss. Normally a 2 million BTU heat loss can be taken by 4 HTP 500 Modcon that will give 20 to 1 turn down which would be the trick for micromanagement of energy usage. In the great white North, only 100 hours are at maximum temperatures for baseboards at 190F, the other 900 hours are on Outdoor reset. Energy savings are between 35 and 50%. BW FTXL have had a number of failures here and we have stopped installing them even when the distributor would provide replacements.

nicholas bonham-carter

I wonder if the original poster is still reading, or if he is now overwhelmed by the different possibilities there could be in the solution to his problem.--NBC