This forum is modconing me crazy

HydroNiCK

I have been a member of this site for years now.  I joined as a young lad after Ken Resnick told my class about it.  Yous guys are a wealth of knowledge which i nerdly enjoy and find helpful as a plumber.  While having said that this site is also contributing to my neuroticism and mental decline.  Knowing too much information often times prevents me from making a decision.  My brain is locked out on high temp thinking about heating.  Currently my nights are spent reading, staring at my pipes, and muttering to myself.  So since this all of your fault I'm going to need your help to set me straight.

My 1964 Utica heated it's last baseboard and after keeping it alive for the last 5 years I've been in the house it it's standing pilot stands no more. You can find my previous posts on it if you'd like and I might even post autopsy pics. The gas was starting to get sucked back into the rails and becoming unsafer-er among other things. So I ripped it out.

The 100,000btu 70% boiler heated 2nd fl apt. 936sqft with 63ft baseboard.  I added a 2600 btu radiant zone to a first floor room heated by mini split. The majority 1st floor is heated by a furnace which Id like to phase out. I installed mini splits and am slowly adding underfloor radiant.  

House born in 1964 is r13/poorly insulated. Heatloss is 65,085 basement included. I'm getting cellulose blown in next week.

My problem:. I can't decide between a modcon or cast iron.  Currently my mother in laws apt has no heat and time is ticking.   I want to get a condensing boiler but know they are finicky. It would be heating baseboard and small radiant zone until eventually 1st floor radiant is completed.I have high iron content in my water so I scratched ibc sl10 off my list.  Im looking at the Knight and reading all the problems people have had with it (which aren't many) but don't see any installers or reps in my area.   I'm thinking it might not be a good time to experiment.  Are they annoying to clean?  Not to mention people are advising to stock up on parts just in case.  It sounds risky. I thought I'd be wiser to install a Minitherm however it uses a 3/4 ng connection.  I'd have to re-pipe my gas before I can hook it up.  Then pipe it to handle my future radiant.  I want the new technology but don't want to hear it from my wife if the modcon is nothing but problems.  Yet cast iron and my future plans might not mesh well.  I can't make a decision because of the negatives I see with both.  I've installed boilers for other people. This decision shouldn't be this hard but since this is for myself I'm paralyzed by the glut of information stored in my head.  I know I sound crazy. It's only a boiler right.... Any advice?

Steamhead

@HydroNiCK , where are you located?

hot_rod

what is the total square footage you are heating?  With a 65,000 load it must be 2500 sq ft or more?

Im not sure finicky is accurate for mod cons. I’ve lived with quite a few in my home shop and in laws places, without any major issues. And no none of them had yearly maintenance, some had no maintenance.

On the plus side for mod cons is the mod part, the ability to modulate even if not condensing. This takes a huge amount of cycling out of the boiler. If in shoulder seasons you can condense, efficiencies go up, way beyond that 70% that you might have now 

yes they are more complex more components to fail. With over 30 years now on the condensers, the bugs are mostly worked out

Any equipment is just an assembly of parts made all over the world, not unlike todays vehicles. So the boiler manufacturers are always depending on the parts suppliers to furnish the best most reliable components. Electronics, fans, gas valves, often the HX

The brand you buy is mostly a name on the sheet metal jacket

All the major brands have reps and dealers across the US and Canada. Although a lot of the best hydronic guys tend to be underground. The don’t always advertise because they have more work than they can keep up with.

The area reps and wholesalers always know who the best and most experienced hydronic guys are.

mattmia2

If you think the size of the gas line going in to the boiler tells you what size gas line you need, you need to do more reading.

SuperTech

I personally feel like cast iron boilers are the best option for high temperature applications.  Maybe add a buffer tank or reverse indirect to reduce cycling.  Actually my favorite option is a steel boiler, the EK-1 Frontier with the Carlin EZ gas burner. 

ChrisJ

mattmia2 said:

If you think the size of the gas line going in to the boiler tells you what size gas line you need, you need to do more reading.

Did you mean to say the size of the gas connection on the boiler does not tell you what size you need?

hot_rod

Did you do an assessment of the heat emitters, determine how often you could run in condensing mod? That could help with the decision also.

The future is is in low temperature hydronics. Ideally you could run condensing mode throughout the heating season.

The best advice is to look at lowering the load as much as possible first, then on to the design and product selection. the more radiant you add the more a mod con makes sense.

https://www.caleffi.com/sites/default/files/file/idronics_25_na.pdf

HydroNiCK

hot_rod said:

what is the total square footage you are heating?  With a 65,000 load it must be 2500 sq ft or more?

Im not sure finicky is accurate for mod cons. I’ve lived with quite a few in my home shop and in laws places, without any major issues. And no none of them had yearly maintenance, some had no maintenance.

On the plus side for mod cons is the mod part, the ability to modulate even if not condensing. This takes a huge amount of cycling out of the boiler. If in shoulder seasons you can condense, efficiencies go up, way beyond that 70% that you might have now 

yes they are more complex more components to fail. With over 30 years now on the condensers, the bugs are mostly worked out

Any equipment is just an assembly of parts made all over the world, not unlike todays vehicles. So the boiler manufacturers are always depending on the parts suppliers to furnish the best most reliable components. Electronics, fans, gas valves, often the HX

The brand you buy is mostly a name on the sheet metal jacket

All the major brands have reps and dealers across the US and Canada. Although a lot of the best hydronic guys tend to be underground. The don’t always advertise because they have more work than they can keep up with.

The area reps and wholesalers always know who the best and most experienced hydronic guys are.

My calc. Is based on 2962sqf.  65000 is on the high side. There are too many windows in this house and I'm getting cellulose blown in. I have a lofted room with too many windows and a cathedral ceiling. The first floor of the room is pine tongue n groove on joists. No sub-floor over a garage. Yes really. I usually keep it out of the heatloss calc. Because it throws it off. That rooms load is 20,000 btus.  SnugPro calculated my heatloss to be 46,000 btu without the loft room.  

The upstairs apt. is 936sf with 63' of 3/4 baseboard, a heatloss 13,070btu, and a mother in law that thinks 73 degrees is too cold.  I started calculating the baseboard and came up with 125 at 1gpm. Don't think that's going to fly because she's not going to be able to toast marshmallows on her baseboard so is going to say that her heat isnt working.

Lochinvar site didn't list any installers or rep within like 50 miles of me.  I thought a compromise might be to get a Laars FT since Rathe is by me. Or maybe a Bosch Greenstar since many install them in my area.  So you see this is what I'm thinking about.  I'd like to install the boiler myself but as someone that has installed mostly Navien modcons I know I don't want a Navien. I'd like to install the knight but don't know how worried I should be as a first time installer of a particular modcon without access to support close by if needed since someone else's comfort is at stake. Therefore cast iron...or not.  But thank you. Your post re-assured me a little that my expectation of a modcons reliability or  mishap or access to parts nowadays might not be total disaster and doom.

mattmia2

Another option is to pipe it primary-secondary with 2 very small mod cons, that way you have redundancy if one mod con fails.

I like HTP's stuff. Lochinvar I think has some more sophisticated config available on some models.

hot_rod

HydroNiCK said:

hot_rod said:

what is the total square footage you are heating?  With a 65,000 load it must be 2500 sq ft or more?

Im not sure finicky is accurate for mod cons. I’ve lived with quite a few in my home shop and in laws places, without any major issues. And no none of them had yearly maintenance, some had no maintenance.

On the plus side for mod cons is the mod part, the ability to modulate even if not condensing. This takes a huge amount of cycling out of the boiler. If in shoulder seasons you can condense, efficiencies go up, way beyond that 70% that you might have now 

yes they are more complex more components to fail. With over 30 years now on the condensers, the bugs are mostly worked out

Any equipment is just an assembly of parts made all over the world, not unlike todays vehicles. So the boiler manufacturers are always depending on the parts suppliers to furnish the best most reliable components. Electronics, fans, gas valves, often the HX

The brand you buy is mostly a name on the sheet metal jacket

All the major brands have reps and dealers across the US and Canada. Although a lot of the best hydronic guys tend to be underground. The don’t always advertise because they have more work than they can keep up with.

The area reps and wholesalers always know who the best and most experienced hydronic guys are.

My calc. Is based on 2962sqf.  65000 is on the high side. There are too many windows in this house and I'm getting cellulose blown in. I have a lofted room with too many windows and a cathedral ceiling. The first floor of the room is pine tongue n groove on joists. No sub-floor over a garage. Yes really. I usually keep it out of the heatloss calc. Because it throws it off. That rooms load is 20,000 btus.  SnugPro calculated my heatloss to be 46,000 btu without the loft room.  

The upstairs apt. is 936sf with 63' of 3/4 baseboard, a heatloss 13,070btu, and a mother in law that thinks 73 degrees is too cold.  I started calculating the baseboard and came up with 125 at 1gpm. Don't think that's going to fly because she's not going to be able to toast marshmallows on her baseboard so is going to say that her heat isnt working.

Lochinvar site didn't list any installers or rep within like 50 miles of me.  I thought a compromise might be to get a Laars FT since Rathe is by me. Or maybe a Bosch Greenstar since many install them in my area.  So you see this is what I'm thinking about.  I'd like to install the boiler myself but as someone that has installed mostly Navien modcons I know I don't want a Navien. I'd like to install the knight but don't know how worried I should be as a first time installer of a particular modcon without access to support close by if needed since someone else's comfort is at stake. Therefore cast iron...or not.  But thank you. Your post re-assured me a little that my expectation of a modcons reliability or  mishap or access to parts nowadays might not be total disaster and doom.

Great support from the Rathe team. The boiler would be very similar to the Lochinvar of the same type, FT fire tube. Typically the installer or wholesaler deals with the rep should issues arrive.

HydroNiCK

mattmia2 said:

If you think the size of the gas line going in to the boiler tells you what size gas line you need, you need to do more reading.

I use  NG sizing tables and draw the whole system out on paper.   I saw that the boiler had a 3/4 inlet and thought to myself "why did they make it a 3/4 inlet. It doesn't need that".  I thought it's obviously for a reason like the boiler sucks a lot of gas quick and it should be piped first in the system or when it fires up they were concerned about it's draw creating a vacuum and blowing a nearby appliance pilot out. After looking at the install manual I see it's a Honeywell gas valve and I could switch out the 3/4 flange for a 1/2" one which if I get that minitherm I would probably do.  However, just like how on a steam boiler your not supposed to reduce the piping from whatever size tapping the mfg provided I thought the same with the 3/4 water connection even though you can't treat water like gas I didn't want to void a warranty or whatever...Let me preface that by saying I was taught to install gas piping in new construction and learned all the practices n nuances that go along with that.  This boiler is residential homeowner finish work and my initial reaction was to figure where I have to cut this branch in because that's what the plan called for.  I barely ever had to install piping then modify it to an appliance I was to buy after the fact or pipe a half inch branch to an unexpected sized inlet.To this day I have never used  csst hose.  So am I a licensed master Plumber able to touch gas..Yes. Do I know everything? No absolutely not. I learn new things all the time that's why I enjoy this forum.  So please correct me if I'm wrong.

HydroNiCK

Steamhead said:

@HydroNiCK , where are you located?

Long Island

EBEBRATT-Ed

You size the gas pipe by the connected load, available pressure, length of run taking into account other connected appliances. The connection size on the boiler means zip

ChrisJ

EBEBRATT-Ed said:

You size the gas pipe by the connected load, available pressure, length of run taking into account other connected appliances. The connection size on the boiler means zip

I just re-read what @mattmia2 typed and it makes complete sense now and yet I swear it didn't the other night.

I'm confused. Maybe I was tired.

hot_rod

You will find that mod cons want a 3/4 line, even though a 1/2" might cover the their load. It's the negative pressure gas valves that work best with a bit more pipe capacity.

pedmec

Are you still using a rotary phone? Still going to the library to get information? Still have a car with a carburetor. I hate to sound negative but we have to stop living in the past. We are moving forward with technology. Jump on the train.

I know that mod/cons require yearly maintenance but so do oil burners. And i never hear customers complain about getting there burners cleaned every year. It's the reality of having oil heat. And now that DOE requirements are going to be 84% for natural gas cast iron boilers wait to you see all the corroded flue pipe and cracked chimneys. I've been seeing it for the past 30 years with fan assisted furnaces which run around 85%.

The price increase of cast iron with the added expense of required combustion air equipment and possible chimney liners have all but eliminated the price difference between cast iron boilers and mod/cons. Plus the smaller foot prints of mod/cons and the piping arrangements have allowed homeowners greater floor space. To me its a no brainer but i'm just one mans opinion. (plus i dont mind not having to carry cast iron boilers into basements, never mind breaking down the old ones to get out of the basement. you do 2-3 a week for a couple of years and it wears on you. my back appreciates it).

ChrisJ

pedmec said:

Are you still using a rotary phone? Still going to the library to get information? Still have a car with a carburetor. I hate to sound negative but we have to stop living in the past. We are moving forward with technology. Jump on the train.

I know that mod/cons require yearly maintenance but so do oil burners. And i never hear customers complain about getting there burners cleaned every year. It's the reality of having oil heat. And now that DOE requirements are going to be 84% for natural gas cast iron boilers wait to you see all the corroded flue pipe and cracked chimneys. I've been seeing it for the past 30 years with fan assisted furnaces which run around 85%.

The price increase of cast iron with the added expense of required combustion air equipment and possible chimney liners have all but eliminated the price difference between cast iron boilers and mod/cons. Plus the smaller foot prints of mod/cons and the piping arrangements have allowed homeowners greater floor space. To me its a no brainer but i'm just one mans opinion. (plus i dont mind not having to carry cast iron boilers into basements, never mind breaking down the old ones to get out of the basement. you do 2-3 a week for a couple of years and it wears on you. my back appreciates it).

There were several reasons I went from an oil burner to an atmospheric NG boiler. One of them was yearly maintenance. Not only do they require far less maintenance, they're cheaper to buy, cheaper to repair and less likely to fail.

I don't see why there would be any issues with B vents or lined chimneys? Perhaps requiring greater than 82% is unreasonable and impractical.

I chose equipment based on the cost of ownership and the amount of possible headaches it could give me. Not by what salesmen told me I needed.

pedmec

@ChrisJ


Ihe pricing of cast iron boilers is the same as a mod/con.

Additional cost to install cast iron is combustion air and possibly a chimney liner.

Combustion air and exhaust is part of the vent package for a modcon.

Sorry, thats pretty much a wash if not in favor of a modcon.

Aluminum chimney liners will only last about 10 years-15 years if condensation happens in the liner. I've ripped out dozens installed in a development i took care of. and its not cheap installing aluminum liner. you can go stainless steel and pay anywhere between 2 and 3 times the cost of aluminum.

And im not a salesman. I have installed and serviced 30 years worth of heating systems. Pretty good amount of experience.

ChrisJ

pedmec said:

@ChrisJ


Ihe pricing of cast iron boilers is the same as a mod/con.

Additional cost to install cast iron is combustion air and possibly a chimney liner.

Combustion air and exhaust is part of the vent package for a modcon.

Sorry, thats pretty much a wash if not in favor of a modcon.

Aluminum chimney liners will only last about 10 years-15 years if condensation happens in the liner. I've ripped out dozens installed in a development i took care of. and its not cheap installing aluminum liner. you can go stainless steel and pay anywhere between 2 and 3 times the cost of aluminum.

And im not a salesman. I have installed and serviced 30 years worth of heating systems. Pretty good amount of experience.

What's the total cost of ownership when failures and maintenance are included modcon vs cast iron atmospheric? How long does the typical modcon last?

We know all boilers *should* be looked at and cleaned yearly but we also know most atmospherics are ignored for many years and go just fine.

SuperTech

Modern oil equipment, especially Energy Kinetics boilers require very little maintenance if supplied with clean oil setup for correct combustion.  I service many that are soot free every year. My WBV Peerless just gets a new nozzle and oil filter every year and stays clean. 

Mod cons are great for low temperature applications but as a service tech I don't like them for the same reason I don't like mini splits.  They all require model specific parts and I can't be sure that I will be able to fix the system at midnight on Christmas eve.  An oil burner or cast iron boiler isn't a problem.  Universal parts are available and I always have what I need on the truck. 

Almost every time I service a mod con or combi that is heating fin tube baseboard they are always in bad condition, especially if its a Navien. 

GGross

"They are all junk when you are out fixing them"
-Quote from my favorite service tech

SuperTech

GGross said:

"They are all junk when you are out fixing them" -Quote from my favorite service tech

I can understand that point view.  Equipment that I can fix quickly with parts on the van keeps me happy and my customers happy.  They don't like it when the supply house tells me that the inverter board or combustion fan motor isn't available for several days. 

The Steam Whisperer

The combination of proprietary parts, wholesalers not stocking repair parts for the boilers they have sold, and shorter life, made me drop modcons ( I was installing Triangle Tubes ( firetube)) years ago. If the CI boiler manufactures would put out a modulating burner with outdoor reset, that would eliminate about 2/3 of the efficiency advantage of modcons.

In the steam world, nearly everything larger than 500,000 btu's we install is modulating, and on two pipe, modulating with outdoor reset. I'm talking to suppliers about adding condensing stack economizers, since our return temps on two pipe steam are about 80F or lower for about 95% of the heating season.

Sal Santamaura

pedmec said:

Are you still using a rotary phone?...

Still have one in the house, a pseudo-antique oak-case thing my wife wanted and I bought for her in the 1980s. But that's really not the applicable analogy. In terms of telecommunications equipment, we have at least one corded phone on each floor. And continue to have plain-old-telephone-service (POTS), i.e. copper to the home, powered by the AT&T central office. During an extended utility power failure, we always have phone service. There are battery banks for short-term and a diesel generator for long-term backup at the central office.
While not arguing against modcons, in a rugged climate I wouldn't have one without some backup form of heat. Belt and suspenders, especially if replacement buckles for one's belt have a high probability of becoming unavailable.

mattmia2

In most places as they replace equipment they terminate the remaining copper to a bridge that connects to the new fiber back to the co so it is no longer powered by the co.

Sal Santamaura

mattmia2 said:

In most places as they replace equipment they terminate the remaining copper to a bridge that connects to the new fiber back to the co so it is no longer powered by the co.

Not here. I don't know if state regulators require them to maintain the traditional powering approach, but as long as it's in place, I'll keep the service. We experienced an extended power failure within the last few months, during which our cell service went down, but the POTS line was uninterrupted. See page 187 here:
https://attdr.att.com/Documents/TP76400/ATT-TP-76400.pdf

SteamFTW

Makes me think of people who get all excited about installing an Internet-enabled door lock and then find themselves standing in the rain unable to get into their house because the power is out…and they had gotten complacent and stopped bringing a key along “just in case”. There’s some great tech out there, in all kinds of sectors, but there’s no shame in choosing “ol’ reliable” over “new-and-improved”, if it lets you sleep at night. A mother-in-law apartment involves a level of risk unlike anything else. I say: respect your gut feeling, whatever it’s telling you. 

archibald tuttle

@ChrisJ i don't disagree that atmospheric boilers are the simplest thing going and you can actually modulate them the same damn way you can turn down your stove burner but most don't have modulating or two stage valves. they control the air input based on what is entrained by the rush of the income gas which is, of course, reduced with a two stage or modulating valve.

unfortunately, it just isn't worth it to manufacturers, what with fancy smancy stuff they can sell for more and with gas getting cancelled anyway to make some sensors and controls that could modulate fire to get the best out of the boiler under certain load conditions. Worse yet, probably the most to be gained would be in use on steam boilers to modulate to create vapor pressure once boiling has started but zero manufacturers interested in that.

@HydroNiCK what was really wrong with your utica, are you saying the burner assemblies were corroded? I haven't tried to get that as a part. But i would never give up a cast iron boiler that wasn't leaking. I am partial to taking a power burner style oil cast iron and slapping a carlin EZ gas on there. You can probably get one for next to nothing that someone took out because a plumber convinced them to put in a modcon. Disappointed they haven't worked modulating into the EZgas platform yet, but it still is a nice setup and i've got half a dozen running so keep basic replacement parts around, but they run and run. Modcons are my last choice unless low temp emitters.