Why are cast iron emmiters and diverter tees no longer used?

SuperTech

I have been researching information on my system at my home, it's a two pipe diverter tee system with cast iron baseboards. I have read a lot about how cast iron doesn't cool off nearly as fast as fin tube, and the cast iron seems to be superior in many ways.

So why are cast iron baseboards radiators no longer installed in New homes? All the new houses in my area ate equipped with furnaces, if a boiler is installed it usually is used for hydro air or fin tube convectors.

Are the builders just doing everything as cheap as possible? It doesn't seem like it is the more efficient option. Are the new methods really better? Why are diverter tees never used anymore?

L Thiesen

Yes, builders try to do the cheap way. Just make it look good and dont care if doesnt work as well as it could have. I used to know a bulder in my area who built some of the biggest homes in the area who would put in $50 fixtures in the bathrooms, Moen faucets and Eljer stools.

Steamhead

Yup- build them as cheap as you can, get as much money as you can, and don't answer the phone when people call to complain. That's how builders and remodeling contractors work. It also explains why Codes had to require things like insulation and better windows before builders would use them.

If you want to be completely disgusted, watch a Ryland home being built. It's amazing these things don't fall apart in two weeks.

STEVEusaPA

But Ryland home are 'built for life'...why would they lie?
Just like Toll (Troll) Bros.
The most skilled craftsmen and busiest person in these poorly built overpriced homes is the punchlist person.

NY_Rob

Installing Cast iron BB is slow work and it's heavy to lug around (2 man job)... and you need the joiner tool to combine sections... and sometimes they leak. It's also 4x the price of fin-tube... so that and the increased labor time to flush/assemble/add fittings/pressure test/install the cast iron vs fin-tube makes fin-tube the low cost winner.

That being said, most here know the tremendous advantages cast iron BB offers over fin-tube. When used with a mod-con CI BB can prevent short cycling, and even regular cycling plus negate the need for a buffer tanks on smaller systems.

SuperTech

That's what I figured. The man who built my house lived in it afterwards, so I think he used cast iron baseboards because he knew the benefits.

And Toll Bros?! They build the biggest POS homes in my area. I'm constantly repairing the work they did.

I'm looking forward to putting more cast iron baseboards and radiators in my house.

hot_rod

If you can do the work yourself, all sorts of options. Occasionally you find free radiators, yours for the hauling.

I've found them very easy to get heat out of, just get HW in and out some how. Even single pipe steam rads will work on hydronic systems.

I drove to Omaha one day and back, 8 hours for a unique corner rad that someone here turned me on to. It was scrap yard bound! Got it at the front steps of a 125 year old home being converted to FA.

EBEBRATT-Ed

@SuperTech ,$$$$$on the cast Iron radiation. I like monoflow but it's not used much anymore. The only disadvantage is getting the air out can be an issue.

Most prefer multiple zones. My house has monoflow (1955) and it works fine. Temps very even

bob eck

Most home owners care more about having A/C in their new homes than the heating.
In my opinion that is why air heating and A/C systems are so popular.
Most home owners will not pay extra for a Hydronic heating system and a separate ducted A/C system.
In new construction you could have an A/C system with Hydronic duct coils and an boiler that will do the heating and if you want certain rooms to be heated by radiant or cast iron / copper baseboard or even aluminum panel radiators.
But with most new construction homes the builder gives a certain dollar amount for the heating and A/C systems and to get Hydronic heating system that would be and extra cost to the person buying the home.

SuperTech

I've never had to bleed air from my cast iron baseboards. I've drained the system a couple times. All the air comes right out of the vents on the returns at the boiler. Maybe that is why I have that strange two pipe diverter tee system?

j a_2

I agree the monoflow system, is of the best..never a problem with a properly installed one...Its when happy hands the handyman puts his paws on it, it gets interesting to say the least....How many simple kick space heaters do you come across that don’t work...I saw lots of them...And yes I definitely agree that the builders and general contractors are the worst...they charge customer top dollar and then search out the dumbest cheapest hacks they can find...Not many shops around here partake in the circus , to many learned the hard way, like me...

SuperTech

I think a good HVAC installer or plumber could install a nice two pipe diverter tee system with TRVs for a competitive price. The TRVs would offer better temperature control than zone valves. If homeowners were more informed on the benefits of the higher mass systems cast iron could make a comeback.

j a_2

SuperTech said:

I think a good HVAC installer or plumber could install a nice two pipe diverter tee system with TRVs for a competitive price. The TRVs would offer better temperature control than zone valves. If homeowners were more informed on the benefits of the higher mass systems cast iron could make a comeback.

Trouble is we Americans sent most of it to China...then we buy it back at an enormous upcharge...I had used some new locally manufactured c/I rads, piss poor workmanship...Cast iron is great, but not to most Jmo

NY_Rob

And here's how they do iron work over there....

https://www.youtube.com/watch?v=yE8A6uMYXmw&t=202s

JUGHNE

A Monoflow system was installed in our bank. The piping hung low below the basement floor joists. 30 years ago they wanted to finish that space and it was my job to raise the piping. Had little idea what I was doing. Could solder pipe and didn't know much else. Raised all the piping up nearly tight to the ceiling, rerouted for best finished ceiling. There were 2 to 3 sets of tees that had been capped from a previous remodel. Never knew that could have been a problem. Air removal was not a problem....didn't know there should have been.
Each convector had an air bleeder on a long pigtail.
The system air venting consisted of an 1/8" air vent tapped into the top of a tee....nothing else. Had a compression tank. No problem with start up.
20 years ago took the entire system out, as major addition was getting the entire building converted to roof top Heat Pumps!.
The copper went into my basement heating system and is still there. 1 1/2" return with 1 1/4" loop around the bank basement.
I will be using the remains of the 1 1/4" for some boiler drains.
The monoflow tees were 1 1/4 x 3/4.....I still have them on my shelves......why??

Tinman

I still install cast iron rads and cast iron baseboard. The baseboard is/can be a one man job in my opinion. I'm pushing 60 and still do it solo. Quiet, effective, and will last forever.

To this day, I'm still not a fan of residential copper fin tube baseboard. It's as close to forced air as hydronics get, except for fan coils of course.

SuperTech

1-1/2" return and 1-1/4" supply?

That makes me think my setup is wrong. My supply from the boiler is larger than the two returns. And my monoflow tees are on the supply pipes rather than the returns like many are installed.

hot_rod

It is quite an involved process to design and calculate a single pipe diverter tee system, properly anyways.

I'd wonder how many folks under the age of 60 every learned the procedure, or maybe took a design class at the Little Red School House? I'd also guess not many M.E.s today could design a diverter t system

Siggy does a good job explaining the B&G process in Modern Hydronics, it involves 16 steps!

That combined with the cost of installing a system would make it appeal to a small % of customers, unfortunately.

Sal Santamaura

L Thiesen said:

...Just make it look good...

In addition to installing cheap, scorched-air junk heating, they don't even make the houses look good. Recent 'designer' lipstick trends have become uglier and uglier.

The worst of all possible worlds. Functional and aesthetic dreck.

SuperTech

It seems like the only new homes I go to that have a proper heating system are the ones that are built to the customers specifications.
Usually they have either high efficiency gas furnaces or mod cons heating hydro air systems or radiant floor heat.
It breaks my heart when I see so many mod cons without outdoor reset connected.
I was at a house built in the early 1800s and it had more PEX in it than I've ever seen before. Several zones of floor heat with hydro air as second stage. No outdoor reset. With it 40 degrees outside he was heating with 180 degree water. It was over 90 degrees in the basement.

hot_rod

The desire to have AC also drives potential heating system choices.

Even in the high mountain regions they are now often seeing weeks of above 90F temperatures. That was one of the last markets willing to accept hydronic heating only systems.

For resale consideration also, virtually all homes and commercial buildings look at AC and FA or VRF options.
It's a tougher sell for hydronics when a second FA system needs to be included.
In some cases mini splits can be an option for cooling or shoulder season heat loads.

SuperTech

Maybe because it's because I'm a technician that I love hydronic heat and admire the engineering that went into diverter tee and other older systems.
After doing some research I was quite disappointed to see why fin tube convectors became preferred. It's all about money and ease of installation. Quality and performance are an afterthought.

hot_rod

Yeah, I think many of us share that love of the older technologies and equipment.
Most, but not all consumers are more into low cost throw, away stuff, including their comfort systems. Probably not even aware of what true comfort is, maybe never experienced it.
Or care to

Solid_Fuel_Man

I grew up in a 1920s threaded monoflo heated house, with fin tube connectors however.

I may be on the fringe here, but let's look into the history of how and why the monoflo was designed and manufactured. Its my understanding that it was to lower costs and use less materials to keep competitive with the one pipe steam guys. It's kind of a hybrid between series loop and primary/secondary when you think about it.

It was designed to allow one large loop around the basement without having all the labor or home runs for each emitter (imagine doing that with copper or threaded pipe).

With the advent of cheap flexible pipe the labor and fittings is minimal to make home runs for each emitter. But I really like reverse return which uses lots of pipe and fittings!

As far as cast iron no longer being installed as emitters, I think it's purely a cost and labor thing. It's already been said that most are unwilling to pay for it, and the perception that it is antiquated and inefficient. We all know better!

That's my take on it anyway.

EBEBRATT-Ed

Monoflow or venture was not invented until the 1950s

Steamhead

If it was that old, it may have been a one-pipe gravity system with Eureka or similar tees.

Solid_Fuel_Man

House I grew up in was built in 1922, but was retrofitted from scorched air to hydronic at some point. Based on a 36"x36" filled in hole by the chimney, asumed to be a gravity air return. But there is little ecidence of any other floor penitrations or ductwork. Large Arts&Crafts home.

All threaded pipe so I assumed it was prior to 1950 as it seems copper would have been used. B&G brand Mon-O-Flo one on each return, two zones one per floor. Had 3 piece B&G circulators when I was a kid, had to oil them every month or so or else they let you know they needed it! Line voltage Honeywell mercury vial thermostats.

Solid_Fuel_Man

https://www.antiquesnavigator.com/archive/2015/07/05/371365825102.jpg

Steamhead

That was a "pipeless furnace" where that 3-foot square register was all it had. Hot air would rise and cold air would drop thru the same grille. The Monoflo system was a major upgrade.

Many houses in the Baltimore got similar upgrades- many steam as well as hot-water.

Solid_Fuel_Man

It's amazing to think that all the attention to detail was given with generous maple woodwork and maple flooring throughout. Yes virtually no heating system was incorporated until much later. There was evidence of a wood cookstove by ember marks in the hardwood flooring. 5 bedroom old house.

Leonard

Never knew how good I had it, 60 year 1 ft high old cast iron baseboards and mono-flow fittings. 1 zone, Very uniform heat.

I'll have to post questions after I take some measurements and make a picture of the layput.

SuperTech

Please post plenty of pictures. See if you can get pictures of the tees, boiler piping and baseboards. I'd love to see it all.