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Boiler Upgrade

I'm currently considering replacing the original boiler in our home that's 31 years old (still works great but is very inefficentI would think)My question is that I'm being told that because of the age of the installation that my house is set-up (meaning current finned registers placements and 3/4" lines/zone set-ups)that considering a newer Condensing High
Efficiency Gas Boiler Weil McClain Ultra series 2 for instance is NOT the way to go BECAUSE I would have to run it at a higher (180)temp THUS not worth the investment (apparwently because it lowers the actual efficientcy this unit would render??)...compared to a conventional type boiler. I would like some other opinions on this as I would like to make the smartest decision when upgrading to the BEST most efficient system the current market has to offer for my house. I realize there might be other consdierations as to size of the house (3000 square feet on 3 levels finished) and insualtion (30 yr old standards...a little light) Your advice will be well taken and very much appreciated. Thank you for any reply you all might have time to make. I also can be reached by phone at 231-865-3298 fully realizing that talking is much easier and faster. Thanks, Regards Steve

Re: Boiler Upgrade

I have a similar situation. However, I was told (by a salesperson) the Ultra could be set to modulate and supply 180 degrees. On a moderate heating day the boiler would fire at say 50% and then modulate up or down depending on the demand. Installing the boiler this way would effectively reduce the efficiency down to 90%. Is that correct or a sales pitch. Thanks.

Re: Boiler Upgrade


Nice, neat arrangement of the boiler & lines---looks like a six-zone setup---perhaps what the heating tech meant was that the finned convectors were designed to operate at 180 degrees, and thus were SIZED accordingly.

The concept behind condensing/modulating boilers and outdoor reset is that they are designed to operate ~110-120 degrees, and thus require 30% to 50% MORE convectors in older installations to keep the house comfortable (as compared to say a new install of radiant PEX tubing).

This is not to say that the condensing boiler and ODR won't work with your current setup, but chances are the house will feel uncomfortably cold---this is especially true in your locality, which I take is Muskegon, Mich.---with the wind off the lake & winter conditions the lowest temps you get (design temperature) must be well below zero.

One option would be to consider a non-condensing by highly efficient boiler that has a much improved combustion design over your present unit---this would be a 3-pass boiler, which is made by numerous mfgrs---Biasi B10, Burnham MPO, Crown Freeport, System 2000,Weil-McLain WGo, Peerless WGO, & others.

These units save fuel by have the gas pass thru several chambers in the combustion chamber to burn most of the fuel---most are rated at 85-87% AFUE.

Outdoor reset would be a good idea in any event.

Before doing any of this, though, get your current boiler tested by a tech who can use a COMBUSTION ANALYZER---they can determine the current efficiency of your boiler----also a first step is to have as much additional insulation blown into the exterior walls & attic (may cost under $1k) to get R19 in the walls & R40 in the attic---this is your first step & can be done without changing your current boiler.

Re: Boiler Upgrade

Nahusa Tech-
Is it possible for the high efficiency boilers to reset to a Delta T rather than the outside reset? Can they be made to supply 180 degrees and modulate firing rate on load demand? I understand that some of the closed combustion chamber boilers have problems with their gasket deteriorating after a few years and can be quite labor intensive to replace. Thanks.

Re: Boiler Upgrade


The only modulating units I'm familiar with use an ODR to modify boiler water temp---of course, the distribution convectors (rads, baseboard) throughout the house are installed & designed to work with delta T in mind.

Comfort of the occupants is a primary consideration---nobody wants to be in a house that's not warm enough no matter HOW much fuel is being saved---with the equipment available today, it's very possible to have plenty of heat, plenty of domestic hot water & low fuel expenses.

The 3-pass boilers I mentioned are tried & true design that have been around for years--they have a high reliability & usually costs less than condensing units---it's very common to see a 30% drop in fuel usage when a new 3-pass is installed.

Re: Boiler Upgrade

Many thanks Nashua Tech...and considering our climate here by the lakeshore (you're very right about that) and the number of covectors I currently have....sounds like the 3 pass is probly the way to go. I don't understand what you mean by an outdoor reset BUT will find out and look into the units you mentioned...is there any one of them (mfg) that you think is superior or a better bet. The age of this Burnham boiler and the fact there are 0 parts available should something go wrong just has me consdidering replacing it BEFORE something goes wrong BUT it has performed flawlessly for MANY years so far....and many say just run it till it breaks ( the heat exchanger I guess they mean) and we all know that will be in the middle of one of these michigan winters. I just happen to have some extra ins. money right now from a storm damage claim we just had here soooo.....was thinking would be a good time to pull the trigger on this. The insulation thing is a problem because unfortuneatley the house is an open timber framed gambrel barn with cathedral in style and the roof offers NO space for additional insulation with the exception of foam on the top with a re-roof project...so will have to live with that for now but do plan to try and add later. Thanks again to ALL that commented and TOHD...I appreciate being able to read/hear it from someone that doesn't have a vested interest in selling me something. Cheers!

Re: Boiler Upgrade


The primary thing I recommend to those in the market for a new boiler is to MAKE SURE YOU GO THROUGH A PROCESS OF GETTING 4-6 QUOTES.

It can be tedious to call & arrange for 6 prospective installers to come to your house, size up the heating needs & make a quote on the boiler mfgr & the price----but there's no other way for the homeowner to get a good idea of who will be the best installer.

The photo you posted impressed me for the neat piping arrangement---this guy knew what he was doing.

As you accumulate the 6 quotes, you will find the choice of mfgr & price estimate they throw at you are widely divergent---but the mfgr & price will tend to dovetail to a common ground with the more quotes you get.

The mfgrs I like the best include the ones previously mentioned, but the final choice of boiler should be left up to the most courteous, helpful & sincere prospective installer.

Believe me, the more quotes you get,THE LESS MONEY YOU'll END UP SPENDING FOR THIS INSTALL!---and you'll get the best boiler for your needs.

Consult the Yellow Pages under "Heating Contractors", also, "Fuel Oil Dealers"---they are licenced to install gas equipment & often charge lower rates.

Any neighbors, relatives, etc. that have had a recent install should be called.

In the Yellow Pages under "Heating Equipment-parts"---these parts houses each have a counterman who knows all the best installers in the area---the COUNTERMAN is a great person to contact (in person, if possible) for a referral.

I like Biasi, Burnham, Buderus, Crown, Dunkirk, System 2000 (Energy Kinetics), Peerless, Slant/Fin, Triangle Tube,Utica, Viessmann & Weil-McLain.

All of these mfgrs have produced good products for years & most of them make boilers & nothing else--their products are aimed at residents & businesses who live in northern climes & experience severe winters---their bread & butter boilers are mostly of cast iron combustion chambers & weigh 600 lbs or more---this type of boiler usually lasts 30 years or more.

These same mfgrs also make more advanced condensing/modulating boilers of stainless steel or aluminum combustion chambers, but these newer units, although very efficient, don't have a long performance track record & may not last longer than 10-15 years & breakdowns seem more common.

Many 3-pass boilers come in oil-fired models--so you will have to research the model numbers to find the gas-fired 3-pass units made by the mfgrs mentioned: Google "energy star boilers product list" to get a site that lists the hundreds of energy-star boilers by the mfgrs we are interested in here---also note that most standard cast iron boilers on the list also achieve the AFUE energy star efficiency of at least 85%, so also should be considered in your final purchase.

Any one of these boilers will see you realize a drop of 30% in your current fuel usage--and are all tough enough to last a long time.

Outdoor Reset (ODR):

Outdoor reset by Tekmar & others is an electronic attachment to the boiler that recognizes that most boilers burn a lot of fuel during times in the heating season when the outdoor temp is above 35 to 40 degrees---these "not so cold" days actually predominate the heating season, & not just in Oct.,Nov., Dec.,March & April.

The boiler has been designed to provide heat during even the coldest sub-zero days & thus always heats the boiler water to 180-200 degrees to meet this challenge--which occurs only a few days a year in most areas.

Outdoor reset goes on the reality that during "not so cold" days, the boiler can heat the water to 120-130 degrees to adequately & comfortably heat the house, thus realizing a considerable fuel savings--so an outdoor sensor of the ODR registers the outdoor temp & instructs the boiler to produce heating water at the appropriately lower temperature range.

Re: Boiler Upgrade

Will do just that...and have printed it out to make sure...many thanks! Wish me luck and only hope I can have ALL the information to make the RIGHT decision because this not so old barn/house deserves it!and you and THOD have certainly helped head that way....Regards, Bigdog :D

Re: Boiler Upgrade

Still in the process of obtaining quotes....4 appts. scheduled for next couple weeks but was wondering if there's a calculation for boiler sizing by adding up the length of current baseboard convectors which I have which is 171' of 3/4" finned baseboard (on three floors finished including the basement) plus a couple small built-in wall units with blowers in a round rock silo/barn style of the house where apparently floor baseboard convectors were not applicable (they are noisy and rather inadequate IMO). The vintage Burnham boiler we curremtly have is a 220,000 input and 180,00 output probly 60% efficient I would guess.Thanks...

Re: Boiler Upgrade


You have to be careful not to completely trust the amount of existing convectors/baseboards in determining an accurate building heat loss---it often leads to oversizing the new boiler.

However, if the house has been comfortable all these years, you can calculate approx. 580 btu/hr for each foot of baseboard and you would have to see if there is a model # or btu output on the fan-driven convectors---they typically put out between 5k btu/hr to 10k btu/hr when the water temp is approx 180 degrees.

The number you are interested in is BOILER OUTPUT.

That would give you approx. 99k for the baseboard and perhaps 10k or 20k btu/hr for the convectors or a rough total heat output of 119k btu/hr.

This would make the old boiler oversized by a hefty amount & has contributed to wasted fuel over the years---it was quite common to add a "fudge factor" to boiler size back then when heat loss calculations were not in vogue---most boilers these days are sold with easily interchangeable burner nozzles or gas valves that can considerably increase or decrease the btu output of the boiler.

Glad to see you are energetic in getting additional quotes.

Boiler Upgrade Update

After all the re-search, quotes, forums...etc.I'm thinking I might just take a chance with this http://www.pexsupply.com/Burnham-ES2-6-ES2-6-175000-BTU-High-Efficiency-Cast-Iron-Boiler IF and When this exsisting Burnham dies (who knows when that might be BUT I want to be ready with a plan) I like Burnham and this unit I have has served me well....no reason not to stick with them I figure....I know this realtivly NEW ES2 has not been out long so will be interesting to watch it's performance and acceptance in the HVAC community and forums....but some of things I like about this unit after talking with the Burnham engineers...is the Cast Iron Block (new design) using the existing masonary chimney (re-lined with stainless of course, a requirement for this unit)...and the BOOST function when using the outdoor re-set (284$ option) available for this unit (for quicker recovery times from set-back temps with my exsisiting baseboard convectors, michigan winters and marginal cieling insulation I can't change at this time (without re-roofing). I will be further re-searching the ES2 and would appreciate hearing form anyone that might be using it.
Thanks again to all at TOH forums for your help , links and input...I really appreciate it.
Regards, Bigdog

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