?s about upgrading to a high efficency boiler

[jasoninct]

I'm a new homeowner
Currently I have:
house built in 1955
natural gas for fuel

HB Smith boiler that is at least 20 years old (per home inspector) 107MBH rated

Heat is baseboard hot water.

Hot water is from a 15 year old AO Smith direct fired heater (44,000 btu input)

I'm seriously thinking about upgrading to a high efficency boiler with indirect hot water.

I would love to install a condensing boiler and be able to take advantage of the tax rebate but I have some concerns. I want to learn what I can so I don't get fleeced by the contractor I hire to do the work.

For a boiler a triangle tube prestige with biult in domestic hot water catches my eye becasue it will allow me to get both efficent heat and hot water in one unit. Possibly save in cost of equipment (one thing to buy instead of 2) and save in cost of installation (1 unit to install)

My concerns:

Is the triangle tube boiler I have my eye on a good boiler?

Will the triangle tube make as much domestic hot water as my existing 30 gal. direct fired that is rated at 40.8 gph?

Is a condensing boiler right for my application? I ask becasue I've read online that hot water baseboard heating systems have a relatively high return temperature and may prevent the boiler from condensing combustion gas which I read is not good for the boiler. Is there truth to this?

Incase a condensing boiler isn't well suited for my needs I've looked into non-condensing boilers. Like a Burnham Revolution, Burnham ES or Weil-Mclain GV. Any opinions about these?

Thanks for helping me figure out what is the best boiler for my house.

[sprintmj19]

I can't speak for the TT, I don't sell them. I prefer the Lochinvar Knight boiler. Every contractor has their favorite. The contractor and installation is more important than the brand. Make sure they have training and stock parts.

There is some limitation to the amount of the domestic hot water that unit will make. Since I don;t sell them, I'm just repeating what others have said.

There's plenty of un-informed contractors that will tell you a high efficiency boiler is not suited for baseboard.

True, it will not condense as much as if you had low temp in floor or ceiling heat, but it will condense and it will be an energy saver.

The most important aspect of a high efficiency boiler is the modulating part. This is where the majority of your savings will be. Any high eff boiler will have outdoor reset (some have indoor reset). You will see savings when the outdoor reset curve is set properly, and the unit will not only condense (somewhat) but also modulate to the correct water temp required, based on outdoor temp.

I have some customers that had an oversized boiler, when replaced by a properly sized (Manual J is a must) boiler and an indirect, saved over half on their gas bills. I have never had a customer save less than 25% when going to a high eff boiler and an indirect for dhw.

High efficiency boilers are always the way to go. Don't get hung up on brand.

[hydronicsman]

Hi Jason, I'm in CT too.

The TT is a great boiler. I love them because they have very little pressure drop through the heat exchanger. Translated: smaller pump or no pump at all needed for proper flow through the boiler. I have a bunch of them out there doing nicely. I like the vertical design of the heat exchanger as well, TT promotes them as "self cleaning" and while I wouldn't go that far, there's something to be said for letting the condensate wash the HX down as it exits the boiler.

The Excellence is mostly suited for one bath small home/condo situations. 180 GPH. Tread carefully there. Indirects have storage for a reason.

A few design days a year your baseboard heat needs 180 degrees water to heat the house. The rest of the time, lower water temps will get the job done. It's those times where you will see condensing action happening, and the warmer it gets outside, the more you'll see it. So, yes, it absolutely makes sense to do a modcon with baseboard.

Consider this: the boiler modulates. Even if it is above condensing mode, it is still changing it's output to the load. Smaller fire=less fuel used. There is no harm to the boiler running high temp, but it would never be there 80% of the time anyway. A boiler mfr would never get approval if that were an issue.

And, your infiltration issues are over. The boiler takes it's combustion air from outside.

The Burnham Revo and the other non condensers you mention are actually semi-condensers, you need to provide a means to dispose of possible condensate with those too. They need more expensive and convoluted vent piping. I've done both. 10 years ago, they were big stuff. Then modcons came along. They are quaint.

Don't forget you are in tax credit territory with the TT. Yankee gas may have some incentives. Where are you?

[jasoninct]

thank you.

You like Lochinvar, my friend who is a liscensed heating contractor certified by viessmann who offered to install what ever I choose likes viessmann.

I like that the triangle tube has internal indirect DHW but I don't know anything about them other than what I learned on their website.

I'm a little torn.

I can probably save $ with the triangle tube. But I'd hate to spend the money and have some sort of issues.

I suppose I should bite the bullet, spend the extra money and put in a Viessmann with an indirect heater. This way the boiler is installed by someone certified to do it and familiar with the products.

[jasoninct]

Don't forget you are in tax credit territory with the TT. Yankee gas may have some incentives. Where are you?

I'm in wethersfield. We have CNG. They do have an incentive program for high efficency boilers. Not nearly what the fed is offering but something is better than nothing.

My only worry about the TT is like you mentioned. The advertised output of DHW is 180 GPH. The direct fired heater I have now is rated at 41 GPH. To me, that means more than 4 times the output.

[hydronicsman]

I have often thought about the Excellence for smaller jobs like capes, small ranches, but the tipping factor was that extra half bath or more and people like long showers. On border line cases, my TT factory rep has always urged me to err on the side of caution. One does NOT want a customer running out of hot water.

But what are we talking about here? How many baths, fixtures, useage, occupants? What kind of house?

As an aside, you might be paying as much for the Vitodens without the indirect as you would for a TT AND a 50 gallon indirect!

[beenthere]

I'm in wethersfield. We have CNG. They do have an incentive program for high efficency boilers. Not nearly what the fed is offering but something is better than nothing.

My only worry about the TT is like you mentioned. The advertised output of DHW is 180 GPH. The direct fired heater I have now is rated at 41 GPH. To me, that means more than 4 times the output.

As long as you don't use more then 3 gallons per minute.

with your tanked water heater. You could draw 20 gallons in a minute and it would all be hot.

[jasoninct]

I have often thought about the Excellence for smaller jobs like capes, small ranches, but the tipping factor was that extra half bath or more and people like long showers. On border line cases, my TT factory rep has always urged me to err on the side of caution. One does NOT want a customer running out of hot water.

But what are we talking about here? How many baths, fixtures, useage, occupants? What kind of house?

As an aside, you might be paying as much for the Vitodens without the indirect as you would for a TT AND a 50 gallon indirect!

My house is a single bath ranch. 1000 square feet of living space and built in 1955.

So far I'm gathering that although a TT with internal DHW may be the most cost effective, but the best choice would be a boiler and seperate indirect water heater.

If I get an indirect water heater do I need to upsize the boiler? The current boiler only heats the house and has a DOE rating of 107MBH. If a new boiler with indirect water heater is installed should the boiler have a higher rating?

[hydronicsman]

The indirect will/should be prioritzed so it gets all of the boiler's output. The relay board that will control the indirect circulator will have this built in. Just have to make sure it's either turned on, or jumpers are in place, depending on the board brand.

For a house with one bath, I generally want to see at least 75K BTU available to drive an indirect, and the indirect a 40 or 50, lean towards the 50 for dump reserve.

I did a job once where the folks had a human carwash shower (well, I do them a lot, but this one sticks out). Mr. HO tells me that with small kids, the shower is the only place he and the missus can get to it. So I better make damn sure they don't get cold water.

Jason, I kid you not when I tell you I filled a 5 gallon bucket in 45 seconds from the rainfall head alone when I was checking flow rates.

I ended up putting TWO 60 gallon indirects in for that one. If they needed any more, they should just move it to the bedroom.

[flange]

triangle is a very nice dependable product. i sell a crapload of them, along with all the other brands, if the owner wants something else. they rarely ever break, aand for me its been one issue in five years, which was a fluke thing, controller lost the program. matching indirect is nice too. if you didnt know, you can buy a ten year full parts and labor warranty. condensing is the way to go with outdoor reset. the others mentioned are nice as well, im just partial to the triangle due to experience.

[hydronicsman]

to agree with you there, flange, I'm fond of the TT too for a lot of reasons.

[jasoninct]

any opinions about TT's smart indirect water heaters?

[hydronicsman]

stuff. Been around for 20+ years. Low pressure drop through the boiler tank side means no need for a high head pump that uses more power. Stainless steel inner tank is accordioned to self de-scale. No pressure drop through it.

As always, properly sized and installed piping and pumping.

Lost track of the jobs I've seen that had them piped 3/4" boiler supply and return. On a zone valve. Not good.