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Re: Replacing Old Furnace/hot Water


A 20 year old boiler (you have a boiler there, not a furnace), may or may not be sufficient cause to replace with a new unit.

You say the old one is "rusting", but where exactly---if it's just the outer covering, and it's not leaking, this won't affect boiler performance & can be easily repaired.

Could you provide more info as to the btu/hr rating of your boiler, how many total square feet in the house, your general location, height of ceilings, type & # of windows/storms.

You can do a free Heat Loss Calculation at the Slant/fin site below to determine how many btus/hour you need to heat your house---this will tell you if your present boiler is oversized & if you need more insulation, tighter windows, etc.

A rough estimate is to take a heat factor number between 30 & 60 & multiply by the sq.footage (30= very tight house, 60 = very drafty house in very cold climate).

Thus a moderately insulated 2000 sq. ft. house in a moderately cold climate would have 2000 X 40 = 80,000 btu/hr amount of heat oozing out if its structure each hour---and thus would need an 80k btu/hr boiler to keep the building warm.

If you are definitely set on a replacement, the Systems 2000 seems way overpriced.

Energy Kinetics makes good boilers, but so don't scores of other mfgrs for much less cash.

If your current boiler is indeed heating at 86% AFUE efficiency (which is not likely for a 20 yr old unit---more like 70% or less)---you wouldn't really gain anything by putting in a new boiler---that's what the System 2000 is rated at.

700 gallons is a lot of oil--the old boiler may be too big for the house, thus a down-rating of the burner (installing a smaller nozzle in the oil burner), or a new unit should drop your oil usage.

The Logimatic control is simply just another OUTDOOR RESET SYSTEM that is overpriced & can be replaced with an outdoor reset by Tekmar, Honeywell, or Taco for much less cash.

Outdoor reset uses an outdoor thermostat to sample the temp--since many days during the winter are "not so cold" the ORS tells the boiler to drop its water-making temp from 180 degrees to 140 degrees & still keep the house warm---this saves a lot of oil over the winter season.

The 3 circulators are no big deal, they only cost $75 each.

What IS a big deal is the indirect hot water heater---any quote you get for a new boiler MUST INCLUDE A NEW INDIRECT as part of the deal.

Likewise, the Weil-Mclain & Buderus seem overpriced because they don't include the indirect (German imports like Buderus & Viessmann are always very expensive).

Do you have natural gas in your area?? --if so, with the brutal cost of oil these days, it may be wise to switch to NG.

You need MORE ESTIMATES from (Yellow Pages) "Fuel oil dealers", "Heating Equipment dealers", and "Heating Contractors"---it's in your interest to get at least 6 more estimates as the choice of equipment and the price WILL VARY WIDELY--you'll also get some installers who don't seem to care--and a few who are enthusiastic & seem interested in doing a good job---select an installer who seems motivated, & keep searching until you find one.

For the Heating Equipment dealers, go in person to talk to the counterman (in the afternoon when things are slow) to get some recommendations as to the best installers in your area---the installer you choose will have a lot to do with putting in a quality system at a reasonable price.

Figure a base price using the equipment at HD/Lowe's: Slant/fin boiler for $1350, Amtol Indirect $700, outdoor reset, installation & remove old boiler $1000 = $3k to $4k---this, of course, is a low ball estimate, but keep the amount in mind.

Read up on the types of boilers at the links below.

The basic boiler is a pin-type cast iron unit (Slant/Fin, etc); the next step up is a 3-pass cast iron unit (Crown, etc.)(recommended), the 3rd step up is a stainless steel condensing, varible output boiler (Peerless Pinnacle)---these get 95% AFUE efficiency, but need periodic adjustment & cost $8k-$12k.

Buying a new boiler system is really a BUYER'S MARKET---there are so many good mfgrs out there that you have a wide choice of excellent equipment----among which are Biasi, Burnham, Columbia, Crown, Dunkirk, EFM, Hydrotherm, Lochinvar, New Yorker, NTI, Peerless, Slant/Fin, Smith, Triangle Tube, Utica, etc.


Re: Replacing Old Furnace/hot Water


My oil fired boiler and burner is 47 years old and it's time to replace them with another oil fired system (I don't have gas line). Before replacing, I'm updating the insulation and air sealing the house as per recommendations from an energy audit. I've done some investigation myself, have asked my friends and talked to couple of oil companies. I've the following questions that still remain unanswered -

1) Outside combustion air to oil burner: I need to install one, since my boiler room will be rather small, after I finish my basement. As I understand, this brings the outside air to the burner directly.

My first question - is it a sealed system, i.e. the cold air goes directly from outside to the burner via a pipe? Or the cold air will come to the boiler room, in which case the boiler room will be really cold in the winter and some of that cold air can leak upstairs too.

Second question - Does this system work with any burner, more specifically, Reillo and Carlin?

2) I want an outdoor reset, does it work with any boiler, more specifically Weil McClain or Buderus?

3) I'll have three zones, one for each floor. Which of the following two is a better option -

(a) Three separate circulator pumps
(b) One circulator pump with three separate zone valves.

In case (a), I'll have hot water at least in two zones, in case a circulator pump is down. However, how frequently do they go down. I've been living in this house for last 12 years and nothing happened to them.

4) I've the following two boilers in mind: Weil McClain WGO (i.e. the one that works with an indirect water heater) and Buderus. Which one is better?

5) I've the following two burner in mind: Reillo or Carlin? Which one is a better option?

Thanks in advance for any information on the above questions.


Re: Replacing Old Furnace/hot Water


1) There are a number of different ways of inducing outside air into the burner system---if the boiler room is too confined then a DRAFT INDUCER or a POWER VENTER is used to get the conbustion products up the flue & out of the house.

Draft Inducers usually use a 4" pipe to suck outside air thru the foundation, & mix it with the warm air in the boiler room so the BR doesn't get too cold---the damper closes during off cycles to prevent cold drafts.

Power venters are usually mounted high on the outside of the building to create negative draft & have the motor, intake & exhaust all ganged together in one package.

DI's & PV's will work with any oil burner---the other option that many installers prefer (at less cost to you if feasible to do) is to use the chimney---since newer boilers have a lower flue temp (new = 300 degrees, old = 600 degrees) they often have to run a 4" stainless steel flex tube up the chimney to get a good draft--this option should be discussed with the installers if they insist on a power venter or draft inducer.

2) Outdoor reset will work with any boiler, are made by Tekmar, Taco & Honeywell, among others, they are highly recommended--they're based on the idea that during the heating season there are a lot of "not so cold" days---since boilers usually heat the boiler water to 180 degrees (usually unnecessarily) the Outdoor Reset tells the boiler on mild days to heat the BW to only 140 degrees--this is still hot enough to heat the house & the domestic tap water & it saves a lot of oil over the course of the heating season.

3) Circulators are the preferred method by most installers of handling the 3 heating zones---as noted, you will still have heat in all 3 zones if one or even 2 of the circs dies at 3 a.m. some night---you simply lift the little cap on the flo-check valve on each zone & hot water will circulate to all 3 zones.

Taco 007 circs are highly recommended for low operating costs, long life & no need for lubrication---3 zone valves & 1 circ is a common option using Taco 570 series ZV's---but as noted, if the one circ fails, you have no heat until the service person can get there & replace the dead circulator---boiler breakdowns don't happen that often, but when they do, they always seem to pick the WORST possible time to die.

4) Weil Mclain Buderus are both excellent boilers--the Buderus is a German import & is highly regarded for workmanship & quality, but so is Weil-Mclain---the WM usually costs lots less---the exchange rate of the euro & the dollar is not in your favor---also installing an indirect hot water heater (usually 40 gallon) is highly recommended---a unit with a stainless steel inner tank is preferred over a coiled inner copper tube, which is less efficient.

There are plenty of other excellent U.S. boilers that are relatively low cost, including Crown, Dunkirk, New Yorker, NTI, Peerless, Slant/Fin, & Utica---they're all U.S. made & highly regarded.

5) Riello & Carlin are both good burners---Riello tends to have the state of the art burner with pre-purge & post purge controls that save oil & keep the combustion chamber clean.

Riellos are more expensive & a little more complicated & often need periodic tweaking---if you live in a rural area there may be a problem getting Riello parts in the event of a breakdown---Carlin & Beckett (especially Beckett) have much better parts availability.

I always encourage people updating their heating equipment to get AT LEAST 4 TO 6 ESTIMATES from different installers in your area---instead of relying on just 1 or 2 quotes---the price quotes, choice of equipment, venting options, & thus the final install price will vary widely---the prospective installer should be enthusiastic, have a knowledge of the items discussed in this post, & do a heat loss calculation & remove the old unit as part of the deal---the more people you interview, the better feel you will have for hiring the right person---the knowledgeable installer who clearly demonstrates a working knowledge of how boilers work is an important component to getting a good install.

A heat loss calculation is done to make sure the installer puts in the right size boiler (neither too small or too large)---if a too large boiler is put in, you'll burn excessive oil needlessly.

A very rough HLC is obtained by multiplying the total square footage of the house's area to be heated (including boiler rooms, etc.) by a heat factor between 30 and 60 (30 = very tight house with tight windows, lots of insulation, 60 = very drafty house with no insulation, drafty windows).

Thus a sample 2000 sq.ft. house with adequate insulation & decent windows in a cold climate is 2000 X 40 = 80,000 btu/hour---this is the size of the boiler needed & the amount of heat in btu's/hour that is bleeding out of the building each hour on a cold day---you can Google "heat loss calculation" if you want to do your own more accurate HLC.

Re: Replacing Old Furnace/hot Water

Thank you very much for your reply. They were very informative. You mentioned DRAFT INDUCER or a POWER VENTER. A third, lower cost alternative mentioned by you is to vent through chimney. Actually using chimney is quite possible in my case since my current boiler uses a 30 ft high chimney. I didn't understand why 4" stainless pipe is needed inside the chimney. Is it to prevent condensation inside the chimney due to lower flue temperature of 300 degree?



Re: Replacing Old Furnace/hot Water


Yes, chimney condensation would be a secondary reason for using a stainless steel coil thru the chimney.

The primary reason is that combustion byproducts rely on a hot chimney to create a draft so the byproducts will move up the chimney---hot air is lighter so it rises up the chimney.

Because of the reduced flue temp down to 300 degrees on the new boiler, the brick innards often don't get hot enough to create sufficient draft---a 4" steel tube is much easier to heat up so a good draft is created.

Re: Replacing Old Furnace/hot Water

> Buderus is a German import & is highly regarded for workmanship & quality, but so is Weil-Mclain---the WM usually costs lots less---the exchange rate of the euro & the dollar is not in your favor---also installing an indirect hot water heater

I went with the Buderus boiler w/indirect hot water heater over the WM. The system was installed in one day (a big plus for me w/my work schedule) -all other bidders needed 2 days to install. :)

A complaint thus far is the new system is noisier than old boiler. But they did install a vent to bring in air, so that maybe some of the noise. Thus far I haven't see any natural gas savings. In fact its costing me $80 a month this summer for natural gas, as opposed to costing me $40 a month for gas during summer months - I used to heat hot water with electric hot water heater. haven't noticed a drop in electric bill since going with indirect. BUT I'm hopefully this heating season, the nearly $300 a month gas bills will be less. Am also using a pellet stove & ceiling fan to supplement heating in a large family room with vaulted ceiling.

Re: Replacing Old Furnace/hot Water

I'm in the process of getting a new heating and hot water system, as well as all new baseboards and I can't agree more with what you said about getting multiple estimates. I have a few tips to pass on from my experience:
First, read and learn everything you can about how these systems work and what the components are. You can also check the web for pricing, how they are installed, etc.
Second, don't just call the local oil company for an estimate. Certainly call them (and maybe two or three other oil companies) but don't be afraid to call several independent contractors too. In my experience, the gas company suggested a gas furnace, the oil company suggested an oil furnace. They may have been more interested in making me a lifelong customer of their product than what was actually best for my needs.
Third, ask your friends, family, neighbors, the local building supply store employees, the plumber, the guy who watches your cat and anyone else you can find in your area what they use for heat, how much the system cost, what the pros and cons of their system are.

When the "experts" come into your home to give you an estimate, DO NOT tell them you've been doing hours and hours of research. Ask lots of questions but let them tell you what they think is best, how they believe the system works. Armed with lots of information from above, you should be able to sort out who actually knows what they are talking about and who is a "fly by night" with little or no experience.

Finally, NEVER let a salesman scare you into upgrading something that is working just fine. I had a salesman tell me a Bederus was only about $1000 more than the bottom of the line boiler system (untrue in my area) and that it was a "forever" system that will last about 100 years. They haven't been making the current systems for that long so I obviously had a psychic salesman.
I had another salesman tell me that I needed an energy audit, which wasn't a bad idea. But then he proceeded to tell me it would cost $1000 and that he had a "friend" who could do it. I chose to contact my local energy company and found out they do low cost energy audits and are not having dinner with my boiler installer anytime soon so they could be more objective.

I asked plumbers, roofers, electricians, cabinet installers, painters, even the guy who mows my lawn about the companies they've used and what their experience was. I looked them up on the Better Business Bureau, I googled company names and found out who to avoid.

I know all this takes time but I work hard for my money and I don't want to waste it. I also didn't want to end up without enough heat in the winter or wasting money on too large a system.

I did decide to narrow it down to two estimators who both made (free) suggestions on what areas were the most important to insulate. They took the time to actually look at each room, measure baseboards, looked at windows and doors, asked about what was in the walls, etc.
I had one salesman who wouldn't even leave the living room while giving an estimate (he never looked in the basement at all) and told me I needed all new pipes and should add them to the attic and basement. Another psychic who just "knew" what system I needed without even looking at what I had.

The bottom line is that these people work on commission or in the case of the independents, they make a profit on what they sell/install. So always keep in mind that some of them are less interested in what you need and more interested in how much they can sell you.

Re: Replacing Old Furnace/hot Water

Does the advice given here for oil hot water heat also apply to oil steam heat? The oldest part of our house dates to 1880, but it's been added on to over the years. It's about 2700 square feet. We bought it eight years ago, shortly after the owner installed a new boiler (Peerless cast iron). I don't know much about the specs for oil boilers, but the model number on this one is WBV-04-150-SP.

We have a separate oil-fired hot water heater. Is an indirect water heater an option for us, too? We thought about solar roof panels, but our house is well shaded by magnificent old sugar maples and I'd hate to cut them down.

The house seems to be reasonably well insulated (at least what I can see in the attic), and we've replaced most of the windows with higher efficiency ones. But we still go through an awful lot of oil considering we keep the thermostat at 62 in the winter and the radiators are turned off in three 2nd-floor rooms. As much as 400 gallons a month in January, typically our coldest month.

Re: Replacing Old Furnace/hot Water


Yes, many of the same points made about oil-fired hot water boilers, also apply to oil-fired steam boilers.

That sounds like a lot of oil being burned in January---do you have any idea what your ANNUAL fuel consumption bill is???

What is your general location???

There are several approaches used to make sure you are not wasting oil:

Do a HEAT LOSS CALCULATION (Manual J)-which calculates how many btu's/hour are bleeding out of your building each hour---for example if 100,000 btu/hr are bleeding out of your building on a cold day, your boiler has to burn about 3/4 gallon of oil to keep the building warm.

Ways to burn less oil can include adding more insulation to exterior walls & attic & crawl space, and perhaps using a smaller nozzle on your boiler to burn less oil.

You can unscrew some of the electric receptacle covers on your lower exterior walls & shine a flashlight to see if there is any insulation in the exterior walls--there should be R19 in the walls; there should also be R40 in the attic.

If there is little or no insulation in the walls, you're wasting oil--you should have some blown in.

The Peerless site lists the WBV-04-150 as having a 1.50/gal/hr nozzle which puts out 180,000 btu/hr.

Many times, your oil service person can put in a smaller nozzle (the WBV can be fitted with a 1.50, 1.25 or a 1.00 gph nozzle)---the smaller nozzle will burn much less oil with a smaller flame that will save a lot of oil.

A very rough heat loss calculation is done by taking the total square footage of the building (including heated basement/utility room, etc.) and multiplying by a heat factor between 30 and 60 (30 = very tight house with double windows, much insulation, mild climate---60 = very drafty house with little insulation, high ceilings & drafty windows, very cold climate).

Thus a 2700 sq.ft. house X 40 = 108,000 btu/hr---if there is less insulation: 2700 X 50 = 135,000 btu/hr.

If there is a lot of glass & high ceilings, etc, then your hourly heat loss could be 180,000 btu/hr.

If you have the standard nozzle on your Peerless WBV the boiler is burning 1 1/2 gallons/hour of oil to output 180,000 btu/hr---offhand, that sounds too high for the sq.footage of the house---if they put in a 1.00/gph nozzle you would burn 1/3 less oil than you're burning now.

If you add the oil-fired HWH, that's a lot of oil being burned.

Definitely call the heating service person & have them check the nozzle size.

In most cases, yes, you can add an indirect HWH to your steam boiler, so this would also help reduce your oil consumption--they cost ~$700--recommended 40 gal units would be Triangle Tube, HTP Super Stor, Crown Megastor, Weil-Mclain, TFI Everheat.

The "hearth" HLC site below allows you to do a heat calc for each room at a time, then add them all up.

There is also a way to calculate the total output of all your radiators by getting the cubic-foot area of each & totaling them all up: Google "calculating radiator heat output" or "sizing radiator btu output" (with & without the quotes).

The Slant/Fin HLC site may take a while to load on your system.


Re: Replacing Old Furnace/hot Water

We're in western New Jersey, Morris County. Our oil bill for the 12 months through July this year was $5,155. We have a contract for $3.49 a gallon that goes through December this year. After that, I'm sure it will be a lot higher.

Our house has high ceilings, and there's a room on the second floor with a vaulted ceiling, no attic above it. I'm sure that's not as well insulated as it should be, but I'm not sure how we'd insulate it further without taking off the roof or taking down the ceiling. I'll check with the heating service people about the furnace nozzle and an indirect water heater, and see about adding more insulation to the walls.


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