I am considering a Ultra 230 boiler and in looking over the documentation I have three questions:

1. What the heck is a "condensing" boiler?

2. Will this boiler system work with cast iron radiators?

3. The piping diagram shows a 12" long connection atop the boiler between the input and output water lines. What keeps this connection from "shorting out" the boiler loop? The note says "don't exceed 12".

Ist call a qualified contractor. The boiler must be installed by them or the warranty will be VOID.
2nd Condensing boilers are the same as high efficiency furnaces. They remove more heat from the fuel to save you $$ on heating your home.
3rd yes it will work well with the old cast iron radiators if it is installed correctly and adjusted for them.
4th this is a bypass line. Yes it is necessary to keep the boiler temp up under certain circumstances. Ask your boiler installer and I am sure they will explain the rest to you.
Remember this is not like an old time boiler. All adjustments are critical and if not done properly can damage or end up costing you more $$ then you will save if not installed correctly.

A condensing furnace is around 90 percent efficient, the combution gasses condensate at these low temperatures before the flue gasses are exhausted, thus the water has to drain out of the boiler. Yes it will work with any radiator. The loop is called a primary loop and usually requires 2 pumps, does this unit do domestic water heating too? Also look into a Munchkin boiler, we have had praise from homeowners, and they a very small and light.

The Weil McLain boiler is a good boiler if used in the correct application. Radiant floors or a cast Iron Radiator application is the best application for this boiler. An Ultra 230 is a very big boiler so you must have either a very large area to heat or you can throw a cat through the cracks in your walls.

The process of removing more than 90% of the usable heats caused condensation as a by-product. Lower efficiency heaters expel moisture as steam, thus the vapor seen outside as a boiler runs. Trapping the moisture and internally and pumping it away helps add a little more efficiency.

The boiler loop is designed to keep the boiler in the optimum boiler temperature range and is required for Cast Radiators. When the zone calls for heat, there is a lot of cold water being pumped back to the boiler. Without the Boiler Loop, you would shock the boiler, which is operating at temperatures reaching 200 degrees with 60 degree or cooler water. This could cause premature failure of the boiler and takes much more energy to heat up. The boiler loop allows the water to be directed in two directions. One being through the boiler to heat up and the second is directed back through the calling zone. You might figure that the water not being pumped through the boiler loop will not help heat the house, not true. As it passes over the boiler loop it does pick up heat. Remember "Heat Seeks Cold?" The zone loop absorbs some of the heat and directs it back into the loop. Does it take longer to heat the zone. Yes. Does it use more energy? No. Think of your car engine. Unless you live in NYC you don't start your engine and floor the gas pedal while shifting in gear. You modulate the gas pedal to compensate for road conditions. The Weil McLain does the same. It modulates it's gas consumption and keeps the boiler running in the optimum range. Picture it as cruise control for your home.

There has been some issues with this boiler and internal leaks so ask your heating contractor if they are aware of this and if they have the proper tools to set up the boiler for your application. Specifically ask them if they have a Combustion Gas Analyzer. This tool is required when setting up the boiler. This boiler is not a boiler you can just take out of the box and use. It’s designed to adapt to different systems and will require an initial set-up to your application.

I hope this got to you in time.

One last note. The new condensing boilers will not save much money on fuel if you run them higher than 140 degrees on the return leg. In many cases they are not recommended when the return temp is high because they will drop from the 90% + efficient status to low 80% if you are lucky. When you combine the high initial purchase cost with very high replacement parts cost and the guarantee of a annual service call and cleaning you may be better off with a much less complicated but less efficient number wise boiler.

If you can live with cast iron radiators at a lower temperature and if there will be enough radiation from the old cast iron radiators at a lower temperature it could work out for you. If you think you will need to raise your water temp up to keep the heat up in the home then I would pass on the newer style boilers.

I am sorry I did not post this in my first post to you.
The other two gentleman are correct as to there working and information.

Check with the boiler manufacturer you are considering using about the lower temps you will have to run for efficiency or do some research on line best to do it now instead of being sorry later.

A discission was awarded lately by a court of law here in Ohio as to the responsibility of a contractor to install a unit in such a way as to cause the equipment to operate as designed with the promised energy savings.
Basically the customer (commercial) had XYZ company install a series of boilers that were stated to run at 90+% efficiency. When there gas bill usage did not reflect this savings the customer took the HVAC company to court. All the experts were called and basically said that the equipment was not designed to condense at a temperature over 135 to 145 degrees. The judge said that the HVAC company was responsible and made an error when suggesting this type of equipment would save the customer money because the equipment would not run in the maximum energy saving mode because the temperature of the building could not be maintained while in condensing mode.

This ruling made the rounds at a few of the supply houses and now no one wants to be involved with the higher efficiency equipment as a replacement unit. They will only use the equipment on new installs that are designed for this type of condensing boiler.

I am considering a Ultra 230 boiler and in looking over the documentation I have three questions:

1. What the heck is a "condensing" boiler?

2. Will this boiler system work with cast iron radiators?

3. The piping diagram shows a 12" long connection atop the boiler between the input and output water lines. What keeps this connection from "shorting out" the boiler loop? The note says "don't exceed 12".
If you have any problems with the Weil McLain Ultra 230, don't count on Weil McLain to help.

Six months after an incompetent heating contractor installed a Weil McLain Ultra 230 High Efficiency boiler and Ultra Plus Indirect Fired Water Heater, the contractor could still not fix the system intermittently turning itself off.

I contacted three heating contractors who had experience with Weil McLain Ultra 230 boilers to diagnose the problems. They concurred that the installation was so screwed up, it needed to be re-piped.

One heating contractor brought along a heating engineer to figure out the mess. The heating engineer contacted Weil McLain that I needed help. The heating engineer found significant problems that could damage and break the Ultra 230 boiler.

Weil-McLain sent a field rep, Tom, to my home. Tom comes with high credentials. I recently Googled him to discover he was leading a continuing education seminar for home inspectors. I, however, could give him no credibility after the antics he pulled.
I was devastated after having expectations of real help from Weil McLain.

First, he said the heating engineer who called Weil McLain should have talked to Tom before giving me an analysis of the Ultra 230 problems.

Tom turned the boiler on for a minute or two. Then he turned it off. He told me that showed the boiler works and does not shut itself down.

The heating contractors who inspected the system said the water intake valve should be open, whereas it was closed. Tom insisted it should be closed, as he "instructs his heating contractors that the valve is the last thing they should close when finishing an installation." The heating contractors told me that because the valve was not properly installed, had it been left open, boiler water would have entered the domestic water supply. So Tom stopped my domestic water from being contaminated, but would not recognize the installation error that caused boiler shutdowns.

I attempted to contact Weil McLain engineers about this detail. Since Weil McLain does not want homeowners to contact its engineers about their problems, I had to use some cunning to talk to an engineer. He said the valve should be open, contradicting Tom.

I picked the best contractor I talked with to promptly fix the gas leak.

Fixing the Weil McLain Ultra 230 was another matter. It needed an expensive re-piping.
I sued the heating contractor. Tom was one of the defense witnesses.

After receiving a cash settlement, I had the system re-piped. Now the Weil McLain Ultra 230 delivers energy efficiency. And it has not shut down once.

As I remain disturbed with Tom's behavior and the likelihood that other homeowners will suffer from his lack of integrity, I wrote about my experience with Weil McLain to the CEO of SPX, the corporate parent of Weil McLain.

Promptly Weil McLain went into CYA mode. They sent an engineer to my home to confirm there was no damage to the boiler from the multiple shutdowns.

I told Tom's manager details of my experience with Tom. I urged him to implement systems at Weil McLain that will protect homeowners from the misconduct of its field reps such as what I experienced.

Tom's manager called me to tell me he "talked" to Tom. The manager gave no details of what they talked about. He said nothing about any discipline. I asked how Weil McLain will protect consumers. He told me essentially gobbledygook about Weil McLain's "Chicago method" and "Boston method." I heard absolutely nothing that would stop such misconduct in the future.

I feel your pain. LOL

When I field inspect problems for various manufactures the standard process is to find out if it is a manufacturer problem or not. If it is not the manufactures problem I tell the owner to call a HVAC company and get it fixed. Now I do usually make the owner aware of the problem areas of his install but I never re engineer the system since I am not there to do that.

When someone tries to call me to court as a professional witness(very expensive per hour) I can only testify that the boiler was OK but the install left something to be desired. The manufacturer does not want to get in the middle since they are only responsible for the boiler itself and not the install.

It is a shame that there are hacks out there that do bad work and no nothing about the equipment they put in but you hired them to start with and I am sure you checked the BBB and the rest of there credentials.

I am also sure you got a minimum of 2 estimates or possibly 3 so you had a choice of who to hire and that the company was certified by NATE or other national testing system for the HVAC industry Do not blame the manufacturer. They make great equipment and test it for a long time before releasing it for sale. Once it leaves the factory with THE INSTRUCTIONS that no one reads who can tell what will happen.

The manufacturers are not involved with police work so they have no way of knowing what goes on with there product once it is out of there hands. I always believe in putting the blame where it belongs. You hired them because they lied to you when they told you they could do your job. It is the install companies fault period and not the manufacturer.

hvac1000 wrote:
> The manufacturers are not involved with police work so they have no way of knowing what goes on with there product once it is out of there hands. I always believe in putting the blame where it belongs. You hired them because they lied to you when they told you they could do your job. It is the install companies fault period and not the manufacturer.


I could not agree with you more.

What I expected from Weil McLain was an objective opinion of the problems.

Instead the Weil McLain rep provided cover for the heating contractor's incompetent installation.

I did not expect Weil McLain to throw the homeowner under the bus to protect the heating contractor. That stinks and it was irresponsible.

((Instead the Weil McLain rep provided cover for the heating contractor's incompetent installation))

It is always best to stay neutral and I never mind telling the homeowner who they might want to call for the repair but I do it in a strange way.

I have them get the yellow pages and as there finger slides down the page I do the yes thing. That way they have a selection and I never say anything bad about a contractor. As much as I dislike bad workmanship I try not to bad mouth anyone by name. It is always possible that the good can have a bad day but at least they should fix there mistakes.

Sorry about your problems especially with such a well respected name as Weil Mclain.

hvac1000 wrote
> Sorry about your problems especially with such a well respected name as Weil Mclain.

That is why Weil McLain rep's covering up the bad installation is especially reprehensible. Tom's and Weil McLain's reputation made fixing the installation take two years longer and cost thousands of dollars more than if Tom had been honest about the problems.

I thought I was careful selecting a competent heating contractor. The contractor had maintained the old boiler for the three years that I owned the house. I thought he had done a proper job.

The contractor had a clean BBB record. He won People's Choice for heating/cooling contractors in my city for two or three years in a row. He was in business about 15 years. He was high bid, but I would rather pay more to get the job done correctly, then take a chance with someone I did not know. However, my trust was totally misplaced. Today this heating contractor is under bankruptcy protection.

> It is always possible that the good can have a bad day but at least they should fix there mistakes.

I gave the heating contractor over six months to correct the multiple problems. I called him 17 times to fix the problems. My family suffered from scalding hot water all through the first winter. When he fixed the scalding water, he made a new mistake that caused boiler exhaust to vent into our living quarters.

The contractor never addressed the problems behind the multiple Weil McLain boiler shutdowns from hard lockouts.

Plus the heating contractor was unscrupulous. Because of sleazy fine print in the contract, I had to pay him an extra $1,000 because the water heater was not included. He claimed I had to pay an outside plumber for the heater. That was not true as I never received an invoice from the plumber, and the water heater installation violated a number of building codes that would have cost a master plumber his license.

For the safety of my family and home, I would not allow that heating contractor to work on my Weil McLain again. I have to protect my family.

Tom from Weil McLain gave the incompetent and unscrupulous heating contractor the protection of his credentials to make it much harder for me to force the heating contractor to pay a competent contractor to fix his mistakes.

In talking to the various heating contractors, I found that they had many examples where they came in and fixed the incompetent heating contractor's installations. But as this is all done behind the scenes, the heating contractor enjoyed an undeserved good reputation.

This is the ugly reality of the heating industry that homeowners need to be aware of.

The good heating contractors should work to make the industry clean by demanding real accountability of their peers who lack integrity. It costs all you money with higher liability insurance. It was the heating contractor's insurance company that paid my legal settlement to re-pipe the boiler. The contractor's reason why he made the insurance claim was that he damaged our home when he drilled holes out the side of the house for the vent pipes. These pipes that emit massive amounts of steam were directly under a bedroom window and next to the backyard door. The placements of the vents violated Weil McLain's installation instructions.

There were many, many problems with the installation that Tom from Weil McLain refused to recognize.

Weil McLain has done nothing meaningful to stop its expert field rep from no longer providing cover to incompetent Weil McLain boiler installations. The only way to stop such irresponsible behavior is to warn homeowners.

hvac1000 wrote
> Sorry about your problems especially with such a well respected name as Weil Mclain.

That is why Weil McLain rep's covering up the bad installation is especially reprehensible. Tom's and Weil McLain's reputation made fixing the installation take two years longer and cost thousands of dollars more than if Tom had been honest about the problems.

I thought I was careful selecting a competent heating contractor. The contractor had maintained the old boiler for the three years that I owned the house. I thought he had done a proper job.

The contractor had a clean BBB record. He won People's Choice for heating/cooling contractors in my city for two or three years in a row. He was in business about 15 years. He was high bid, but I would rather pay more to get the job done correctly, then take a chance with someone I did not know. However, my trust was totally misplaced. Today this heating contractor is under bankruptcy protection.

> It is always possible that the good can have a bad day but at least they should fix there mistakes.

I gave the heating contractor over six months to correct the multiple problems. I called him 17 times to fix the problems. My family suffered from scalding hot water all through the first winter. When he fixed the scalding water, he made a new mistake that caused boiler exhaust to vent into our living quarters.

The contractor never addressed the problems behind the multiple Weil McLain boiler shutdowns from hard lockouts.

Plus the heating contractor was unscrupulous. Because of sleazy fine print in the contract, I had to pay him an extra $1,000 because the water heater was not included. He claimed I had to pay an outside plumber for the heater. That was not true as I never received an invoice from the plumber, and the water heater installation violated a number of building codes that would have cost a master plumber his license.

For the safety of my family and home, I would not allow that heating contractor to work on my Weil McLain again. I have to protect my family.

Tom from Weil McLain gave the incompetent and unscrupulous heating contractor the protection of his credentials to make it much harder for me to force the heating contractor to pay a competent contractor to fix his mistakes.

In talking to the various heating contractors, I found that they had many examples where they came in and fixed the incompetent heating contractor's installations. But as this is all done behind the scenes, the heating contractor enjoyed an undeserved good reputation.

This is the ugly reality of the heating industry that homeowners need to be aware of.

The good heating contractors should work to make the industry clean by demanding real accountability of their peers who lack integrity. It costs all you money with higher liability insurance. It was the heating contractor's insurance company that paid my legal settlement to re-pipe the boiler. The contractor's reason why he made the insurance claim was that he damaged our home when he drilled holes out the side of the house for the vent pipes. These pipes that emit massive amounts of steam were directly under a bedroom window and next to the backyard door. The placements of the vents violated Weil McLain's installation instructions.

There were many, many problems with the installation that Tom from Weil McLain refused to recognize.

Weil McLain has done nothing meaningful to stop its expert field rep from no longer providing cover to incompetent Weil McLain boiler installations. The only way to stop such irresponsible behavior is to warn homeowners.


It is a shame you had to go through all this stuff. You probably have 100 hours or more just on phone calls and hanging around the house for the repair men that never fixed it to start with.

High efficiency units are not as easy to install as the old style boilers. You need 2000.00 worth of test equipment just to fire them over and set the controls to get the proper energy efficiency out of them. People are paying for many high efficiency heat and cool units and have no idea the installer has no idea how it really works. Good luck on any future purchases. This one taught you a valuable lesson to learn from.

I am considering a Ultra 230 boiler and in looking over the documentation I have three questions:

1. What the heck is a "condensing" boiler?

2. Will this boiler system work with cast iron radiators?

3. The piping diagram shows a 12" long connection atop the boiler between the input and output water lines. What keeps this connection from "shorting out" the boiler loop? The note says "don't exceed 12".

It is a new style of boiler that is more efficient because it transferrs more energy you paid for into your home as heat.

A condensing boiler likes water temperatures at about 130 degrees on the return water end If the water temperature goes higher like 160 degrees recommended for baseboard/cast iron radiators the condensing boiler will not work at top efficiency and in your case might not be worth buying since you have cast iron radiators.

I do not have the diagram so I am not going to guess. That question is better asked of the professional HVAC contractor that is going to do your install.

I will say that these are great Mod/Con style boilers and many are in use today. The parts to repair them are expensive after the warranty is over.

I might dare to say that you might call the company and ask for there advice as to who they recommend to do your install. Hopefully you will have better luck than the other poster.

I would never turn off a water supply valve to a boiler... that is ridiculous. That's why there is an autofill installed, to insure that the boiler will fill itself when necessary. And as far as boiler water getting into your domestic water, that's why it is code to install a backflow preventer.
The heat exchanger in an ulta is extremely tiny, especially compared to old boilers which can hold gallons and gallons of water. That is why you need the primary loop, to ensure proper waterflow through the heat exchanger. Then the amount of water needed to feed whatever zones are calling for heat is pulled from the loop when it exits, and put back in when it returns. If only one zone were calling with 3/4 supply piping, there wouldn't be enough water running through the boiler, shutting it down to protect itself.
If you are still looking into getting this boler, you MUST make sure your contractor is doing this! If they fight you on it, they have noooooo idea what they are doing. This boiler has great features like automatic reset, but must be done properly, its not even close to a push/pull install.

Who was the contractor that you hired to fic the problem? I am having similar issues.

Weil McLain provides factory training specifically for their condensing boiler line as do most of the manufacturers of condensing high efficiency boilers. One should ask if the contractor they intend to hire has a certification from any of these manufacturers.

Cast iron radiators were designed for low temperature operation and are nearly perfect for the condensing boiler. Since the cast iron radiators for the most part were driven by gravity (not pumps back then) a primary/secondary pump arrangement is not necessary nor beneficial as two pumps double parasitic electric consumption.

Weil McLain requires P/S pumping on everything as does Buderus and others, but IBC, Triangle Tube and yes Munchkin - now HTP - also allow smart guys to do it right.

Any condensing boilers is only as good as the installation and local support.

First start with a proper heat load analysis. This requirement will eliminate 9 out of 10 prospective contractors and make your search a short one.

"It is a new style of boiler that is more efficient because it transferrs more energy you paid for into your home as heat."

I installed my first low-mass, PVC vented 91% efficiency condensing boiler in 1987... hardly new.

Please provide me with the manufacturer name of that 91% boiler. I am just curious since I have been in the HVAC biz for many years and in 1987 I do not remember a condensing boiler available in my area at any of the distributors. Thank you

Glowcore. Though HeatMaker was also available at the time.

As soon as I read Glowcore I thought of Heat Transfer Products Company which made them. They have not been around for a long time and I believe they had some problems with there burners but I only worked on one or two of these units and they worked fine after a small part replacement or adjustment. It has been to many years ago to remember exactly what was wrong with them to start with just guessing here. That is what happens when I got older since I have forgot more manufactures names than I remember.

One last note. The new condensing boilers will not save much money on fuel if you run them higher than 140 degrees on the return leg. In many cases they are not recommended when the return temp is high because they will drop from the 90% + efficient status to low 80% if you are lucky. When you combine the high initial purchase cost with very high replacement parts cost and the guarantee of a annual service call and cleaning you may be better off with a much less complicated but less efficient number wise boiler.

If you can live with cast iron radiators at a lower temperature and if there will be enough radiation from the old cast iron radiators at a lower temperature it could work out for you. If you think you will need to raise your water temp up to keep the heat up in the home then I would pass on the newer style boilers.

I am sorry I did not post this in my first post to you.
The other two gentleman are correct as to there working and information.

Check with the boiler manufacturer you are considering using about the lower temps you will have to run for efficiency or do some research on line best to do it now instead of being sorry later.

A discission was awarded lately by a court of law here in Ohio as to the responsibility of a contractor to install a unit in such a way as to cause the equipment to operate as designed with the promised energy savings.
Basically the customer (commercial) had XYZ company install a series of boilers that were stated to run at 90+% efficiency. When there gas bill usage did not reflect this savings the customer took the HVAC company to court. All the experts were called and basically said that the equipment was not designed to condense at a temperature over 135 to 145 degrees. The judge said that the HVAC company was responsible and made an error when suggesting this type of equipment would save the customer money because the equipment would not run in the maximum energy saving mode because the temperature of the building could not be maintained while in condensing mode.

This ruling made the rounds at a few of the supply houses and now no one wants to be involved with the higher efficiency equipment as a replacement unit. They will only use the equipment on new installs that are designed for this type of condensing boiler.

Almost perfect.

Except, the by-pass, or primary/secondary (P/S) pumping is required to keep minimum flow through the low-mass heat exchanger used by most condensing boiler manufacturers. The addition of a by-pass or two pump, primary-secondary pumping can be a detriment to high efficiency potential, since they may increase return water temperature to the boiler and always add the parasitic cost of the second pump, without adding anything to the performance of the boiler or system.

When replacing boilers in older homes with one thermostat (zone) here in the Twin Cities, we use IBC, Lochinvar, Triangle Tube, Viessmann, and HTP products, as they appreciate the fact that every boiler system is a custom design. By contrast, Buderus, Burnham, SlantFin and Weil McLain specifically mandate the use of P/S pumping in all application new and retrofit, voiding the warranty if P/S is not used. The simple majority of the condensing boiler manufacturers do require P/S pumping to protect their boilers from overheating and only those familiar with the technology should deviate from this "idiot proof" policy.

The high efficiency condensing boilers are a perfect match for almost any old gravity cast iron radiation system, as they were originally designed for relatively low operating temperatures and often may operate well below the original design water temperature with the reduced heat loads often found in older homes with upgraded windows and insulation. Our best fuel savings matching a "then new" Lochinvar Knight to the cast iron radiators of a 1921 bungalow in St.Paul, MN. The local gas supplier came out three times to check their gas meter as the fuel bill had gone down over 60%.

Had I been an expert witness for the contractor in the "Ohio" case, I doubt the outcome would have been the same. Regardless of application, a properly installed condensing boiler will typically operate at 88.6% combustion efficiency in the coldest weather, delivering 180°F water to the system and not condensing at all. In cold climates the design condition (coldest week of the year) is so short that the bulk of the year much lower temperatures can be used to heat the space. It is in the shoulder months that the condensing boiler saves the most on fuel in non-typical applications such as fin-tube baseboard, fan coils and cast iron radiator.

There is much confusion over the savings available from condensing boilers. For instance it is the "return" water temperature that lowers the flue gasses to dew point and recovers the energy. So any system designed to operate with a return below 140°F will likely condense a good part of any heating season. All condensing boiler available in the US and Canada today feature weather sensitive controls, which modulate the flame and consequently the output and average water temperature of the system.

Those who downplay the inherently superior performance of condensing boilers willingly the ignore the obvious advantages and real-world saving of this superior technology including, sealed combustion (shutting down the drafty chimney), weather sensitive control (lower operating temperatures on all but the coldest days and reduce flue temperatures (from 400°F to less than 150°F).

When choosing a high efficiency condensing boiler one should seek out the local expert, whom you will recognize by his certificate of competency, issued by any condensing boiler manufacturer and the sample heat load he provides since sizing any boiler is the first critical step in any hydronic heating design.

As soon as I read Glowcore I thought of Heat Transfer Products Company which made them. That is what happens when I got older since I have forgot more manufactures names than I remember.

Sorry, Heat Transfer Products did not make GlowCore boilers. In fact we bought some of the first indirect-fired-water heaters from HTP to make the first condensing boiler/indirect package in the country. HTP did not come out with the Munchkin until 2000 or so. GlowCore made condensing boilers from 1985 to 1995 or so. But I can relate to memory loss...

Almost perfect.

Except, the by-pass, or primary/secondary (P/S) pumping is required to keep minimum flow through the low-mass heat exchanger used by most condensing boiler manufacturers. The addition of a by-pass or two pump, primary-secondary pumping can be a detriment to high efficiency potential, since they may increase return water temperature to the boiler and always add the parasitic cost of the second pump, without adding anything to the performance of the boiler or system.

When replacing boilers in older homes with one thermostat (zone) here in the Twin Cities, we use IBC, Lochinvar, Triangle Tube, Viessmann, and HTP products, as they appreciate the fact that every boiler system is a custom design. By contrast, Buderus, Burnham, SlantFin and Weil McLain specifically mandate the use of P/S pumping in all application new and retrofit, voiding the warranty if P/S is not used. The simple majority of the condensing boiler manufacturers do require P/S pumping to protect their boilers from overheating and only those familiar with the technology should deviate from this "idiot proof" policy.

The high efficiency condensing boilers are a perfect match for almost any old gravity cast iron radiation system, as they were originally designed for relatively low operating temperatures and often may operate well below the original design water temperature with the reduced heat loads often found in older homes with upgraded windows and insulation. Our best fuel savings matching a "then new" Lochinvar Knight to the cast iron radiators of a 1921 bungalow in St.Paul, MN. The local gas supplier came out three times to check their gas meter as the fuel bill had gone down over 60%.

Had I been an expert witness for the contractor in the "Ohio" case, I doubt the outcome would have been the same. Regardless of application, a properly installed condensing boiler will typically operate at 88.6% combustion efficiency in the coldest weather, delivering 180°F water to the system and not condensing at all. In cold climates the design condition (coldest week of the year) is so short that the bulk of the year much lower temperatures can be used to heat the space. It is in the shoulder months that the condensing boiler saves the most on fuel in non-typical applications such as fin-tube baseboard, fan coils and cast iron radiator.

There is much confusion over the savings available from condensing boilers. For instance it is the "return" water temperature that lowers the flue gasses to dew point and recovers the energy. So any system designed to operate with a return below 140°F will likely condense a good part of any heating season. All condensing boiler available in the US and Canada today feature weather sensitive controls, which modulate the flame and consequently the output and average water temperature of the system.

Those who downplay the inherently superior performance of condensing boilers willingly the ignore the obvious advantages and real-world saving of this superior technology including, sealed combustion (shutting down the drafty chimney), weather sensitive control (lower operating temperatures on all but the coldest days and reduce flue temperatures (from 400°F to less than 150°F).

When choosing a high efficiency condensing boiler one should seek out the local expert, whom you will recognize by his certificate of competency, issued by any condensing boiler manufacturer and the sample heat load he provides since sizing any boiler is the first critical step in any hydronic heating design.

The Ohio case was interesting. What it came down to was the fact that there was not enough radiation surface available to heat the structure without running the condensing boiler at 180 degrees. It was a fan coil system and that added to the problem. The original contractor that installed the condensing boiler did not take the lack of heat radiation surface into consideration since it had always done the job before with the old boiler. He had told the customer and put in writing that the system would work as advertised which was 92 or 93 % efficiency but when operated at a higher temperature it was less than you mentioned at 82% or so efficient. The customer felt he was cheated since his utility bills were still quite high. In other words the court ruled that the customer did not get what he paid for and that brings me to the root cause of the problems around here with high efficiency boilers.

Not many HVAC company's around here really have a pro on staff that knows how to sell condensing boilers properly and after they are sold no one to properly service them. I am sure there are a few but not many since this is not real boiler country at my location.

The next item I see time after time. Lack of proper design on replacement type installs. Almost all the systems are short on heat radiation. Since there is not much cast iron here it is mostly copper baseboard and some fan coil systems originally designed to run at 165 to 180 degrees. If you do not have enough feet of copper baseboard you have to run a higher temp water to maintain the temp in the structure when it gets real cold outside. You and I know there are controls that can vary the boiler temp and most if not all mod-con condensing boilers have this control as part of the package from the factory but years ago this was not included in some of them so most of the company's did not install a good old Tekmar 256 or similar to help eliminate part of the problem.

You see and service many more boilers in your area as I mentioned before and that gives you an edge on knowledge much more so that the locals here. I have been retired for many years but still enjoy talking about it and every once in a while fixing a problem.

I still run my dependable Paloma style system here. I test it every year with my old dependable UEI KM900CO/P Combustion Efficiency Analyzer and it is at 80% during high fire every year. I also send the meter back to UEI every year to have it calibrated. I know it is old but at one time it was the cats meow. That Paloma has been in since 1980 or 1981 and so far my design for this 2600 sq. ft. house has worked well. My gas bills are real cheap as compared to others in this area of similar size homes. In 30 plus years the Paloma has only needed 8 real services when a part went south and usually that is the diaphragm in the water valve used for gas safety and to prevent dry fire. One expansion tank (internal rubber duck went bad) and one Grundfos pump. It has been a great unit and I have enough spares to keep it running long after I am gone if anyone knows how to work on this simple machine. Note: I have always kept the gas pressure a bit low and that has kept the heat exchanger it in like new condition and no signs of burn out. I might loose a bit of BTU's but did not need them all to start with.

Thanks for posting back on some of this stuff since I always find it interesting to read other peoples perspective on equipment and gain some additional knowledge. I have never met a man or a woman in the heating business that new it all. It is impossible in today's world when something new is developed every few months. ( I will be learning till the day I die). Thanks again.

I appreciate your knowledge and experience. It is true that many of the early fin-tube systems (then trying unsuccessfully to compete with emerging forced air, were short of radiation.

One point must be considered further.

"when operated at a higher temperature it was less than you mentioned at 82% or so efficient."

We design and install many high efficiency condensing boilers and all will produce combustion efficiency at 86%+ regardless of the operating water temperature if the burner is tuned properly, most of them out-of-the-box on NG. Further, the lack of chimney and built-in outdoor reset will save another 5% on the typical fuel bill, so unless the fin-tube was inadequate to heat the space at any temperature a minimum 10% fuel savings should be automatic.

It is good to remember that it never pays to oversell but this one smells bad to me. I fear it was the contractor that didn't get what he bargained for and the category that suffers most.

As soon as I read Glowcore I thought of Heat Transfer Products Company which made them. That is what happens when I got older since I have forgot more manufactures names than I remember.

Sorry, Heat Transfer Products did not make GlowCore boilers. In fact we bought some of the first indirect-fired-water heaters from HTP to make the first condensing boiler/indirect package in the country. HTP did not come out with the Munchkin until 2000 or so. GlowCore made condensing boilers from 1985 to 1995 or so. But I can relate to memory loss...

I appreciate your knowledge and experience. It is true that many of the early fin-tube systems (then trying unsuccessfully to compete with emerging forced air, were short of radiation.

One point must be considered further.

"when operated at a higher temperature it was less than you mentioned at 82% or so efficient."

We design and install many high efficiency condensing boilers and all will produce combustion efficiency at 86%+ regardless of the operating water temperature if the burner is tuned properly, most of them out-of-the-box on NG. Further, the lack of chimney and built-in outdoor reset will save another 5% on the typical fuel bill, so unless the fin-tube was inadequate to heat the space at any temperature a minimum 10% fuel savings should be automatic.

It is good to remember that it never pays to oversell but this one smells bad to me. I fear it was the contractor that didn't get what he bargained for and the category that suffers most.

The contractor did bit the bullet on that deal but I am sure he learned a valuable lesson also. Do not do any job if you do not have the skill level to complete it properly. Lets face it there are good and bad contractors. I always thought I was one of the good guys but I am sure someone somewhere was not happy with my service usually because of price. Somewhere around here there is a big book of thank you letters etc. from customers. My wife made the book to remind me of my past and when I give a class (which is vary rare now) to show the students that you do not have to rip people off to make a good living and have a successful business. If you treat people right they will always call you back when they need something else fixed.

"not happy with my service usually because of price"

If they got what they paid for, the price was right. I would let you do my work.