Reducing Coupling on Two Upstairs Radiators at end of run causing Problems?

ww

Two upstairs radiators on the far end of the run have reducing fittings from the normal size hot water pipe feeding the radiators of appoximately one inch plus or minus down to maybe a half inch copper pipe.



It took awhile for the last radiators on top and bottom floors to get hot recently and wonder if that reduction impedes the flow of water and the circulation of the hot water to those radiators and others in house when there is a call for heat?



Old Delco Boiler, Beckett AF, 2 family house, burner recently tuned up.

billtwocase

sounds like

you have a mono-flow system. That would be normal size piping for that. Has there been any change to the piping? Burner down fired when serviced? Radiators been checked for air?

ww

these are the only two radiators in house with these small pipes

  both floors get heated by the boiler and one circulator.

no new piping. burner was serviced filters,nozzle,electrodes,etc.

these small pipes were put in because the fittings couldn't be removed on radiators at the time and prevented the larger pipes from being used.

icesailor

Squared Off:

"Pipes increase as do their squares".

That means that it takes four 1/2" pipes to equal what a 1" pipe will do (or carry).

They should have at least piped it in 3/4". It was easier and cheaper for someone (lazy) to run 1/2".

ww

Photos of Piping

Some photos of piping.

billtwocase

looks like

3/4" pipe to me. I would like to see basement pics of the piping. If this is set up monoflow, it will and should work fine. Looks like 1-1/4 piping?

ww

pipe measurements

these are all OD measurements:



copper pipe: 5/8

system inlet and outlet pipes from floor: 1 1/4

reducer fitting in radiator:

inside: 13/16

outside: 1 11/16

I imagine the reducing fitting in radiator can be changed. I was told this was done this way because this fitting could not be removed.

From what I think and what I'm told this would cause a circulation problem.

JStar

Piping

1/2" pipe can carry about 15,000 BTUH. 3/4" can carry about 40,000 BTUH. Do you know the rating of the radiator?



I would be more worried about the way it's piped. The supply should enter the radiator on top, with only the return on the bottom.

ww

supply and return pipes

are on the bottom of all radiators in the house. No problems heating here except two on top. Only difference in all is the two radiators on top as explained with the small pipes.

icesailor

All crossed up:

""The supply should enter the radiator on top, with only the return on the bottom""



Not necessarily. if it is a pumped radiator, it is better if both the supply and return are piped into the bottom. If the supply and return are piped to one end of the radiator, it may not heat the opposite end. If you put the supply on the high side of one end and the return is on the bottom of the other end, the heated part of the radiator can run on a diagonal with the outside of the triangle being cold. The longer the radiator, the easier it is to happen. The harder/higher it is pumped, the greater possibility it has to happen. It will do it the least when both are piped into the bottoms.

icesailor

Two radiators:

I think that the radiator that was there in the beginni9ng was moved and the one there is the replacement. There is a notch on the bed molding to the left of the radiator and the other radiator feed goes past it. The bottom bushings have never been out of the radiators in place now. They set the radiator up on bricks but unscrewed the valve/unions and replaced them with those copper adapters.

You really need someone that knows what they are looking at to decide how to proceed. The original radiator must have worked. If only the radiator could talk and tell its tales.

ww

solution to situation...

I think I'll at some point drain the water a bit from the boiler so that it will be below the top floor radiators. Then repipe this with bigger pipe and fittings. According to what I see here and what I'm thinking it will work better with the bigger pipes than what is in there now.



one more thing..there are two radiators that are in the room and piped together.

Steamhead

Not the first time I've seen this

and it won't be the last.



This was probably a gravity system, judging from the pipe size and spacing. Gravity systems used larger pipes because there were no circulator pumps back then, and this kept the resistance low enough that the water would circulate on its own.



For some reason the original radiators had to be replaced- maybe they froze? The replacements came from a newer system that always had a circulator, and used smaller pipes as a result. But they did not replace the reducing bushings in the radiator to accommodate the pipe sizes your system uses. So the water is going everywhere but those two radiators, because the small pipes have so much more resistance than the originals.



You have the right idea. But it might be well to have a pro do this work, since getting those old bushings out can be difficult if you don't have the right tools.

SWEI

Help me get uncrossed

Most current radiator manufacturers recommend piping which will result in diagonal flow.



Are they missing some critical data?

icesailor

Flowing on a bias:

I don't know what the radiator manufacturers are saying but, the new "modern" radiators are usually 1 1/4" or 1 1/2" on the bottom and 1" on the top. Either way, most I see, old or new are piped with the supply and return on the bottom. In retro-fitted old houses, they were often piped on the same end because of convenience. On gravity systems where the flow is slow but the volume is high, the hot water rose diagonally from the bottom inlet and rose to the top. Where the cooler water in the radiator, being heavier that the hot, went out the bottom return. Only in grossly over pumped system did I ever see a problem where the hot water went in so fast that it beat the cold water out. People that don't understand that the water flow through a gravity system without a pump might have the same flow as a properly designed system with a pump. Many look at all that water and thing that a bigger pump will do the job better. When in fact, it will make it worse. There's very little restriction in the 1 1/4" gravity pipes but a ton of it in the 1/2" pipes. I'll bet that the circulator is grossly oversized. If it was a three speed circulator, I bet the radiators would start working if they ran the pump on the lowest speed. Or, but a 4-way mixer on it and ran the system circulator on ODR. To prove my point, open the flow check so the system runs on gravity. Disconnect power to the circulator. Set the high limit to 140 degrees and let it run. In a few hours, both those radiators will be as toasty as the rest of them. Once the temperature evens out, the system will balance out. Like when you forget to close the flow valve when you work on a system or drain the house for the winter. The customer will be calling back telling you that the house is too hot and the thermostat is satisfied. It goes along with forgetting to turn the power switch back on before you leave. Both things I have done consistently.

SWEI

Gravity flow

is a different animal for sure.



I was referring to European plate radiators, a la Myson or Runtal.  We derate them by 5% for inlet/outlet on the same end, but when there is room, we pipe them diagonally per the manuals.  I was just wondering if there was a better way.  Probably time to invest in an IR camera.

icesailor

IR camera's

IR Camera's are nice. Expensive too.



You'd be surprised what you can tell with  IR thermometer gun. For a lot less money.

A pumped Hydronic system is just a gravity system with a pump.

Turn off the power to the circulator and open the flow check. Given time, the whole system gets hot. ODR will solve a lot of problems with Hydronic systems. Pumped or gravity because of the long run times with the same temperature fluid.

SWEI

No arguments here

When properly implemented, ODR and (more) constant circulation create a level of comfort that most customers have never experienced.



I have a fantastic IR thermometer (Fluke 568) but I'm ready for the next step.  Been watching the prices drop for about a decade now.

icesailor

Wise move:

Wise move to wait.

I just bought a Ryobi Inspection Scope. A few years ago, an electrician friend bought one from HD and got it in sale for less than $150.00. I just bought one for $99.00 from HD. Fine for what I wanted it for. I'd have liked to bought a better one but for less than $100.00, I couldn't go wrong. I found an antique empty 16 OZ can of Miller High Life beer in the wall behind the shower in my FLA Condo.

ww

I've taken another photo of the two radiator setup.

As you can see there are two pipes coming from the floor which are 1 inch. The radiators are connected using 1/2 inch copper. There are no shutoff valves.

1. I have to figure out if I am going to join these two radiators or just put one in for now. these radiators are small compared to the other radiators in house. I don't mind putting one in first since it's on the top floor and I can drain some water off easily. Maybe a new radiator?

2. How do I set up the valve..which side of radiator...and which pipe coming from the floor?..I guess I have to figure out which is the fill pipe and which is the return pipe..what is best way to do that?

3. From what I can see I will take off that reducing fitting from one inch to 1/2 inch copper and install a 90 degree nipple leading into the radiator reducing fitting that has to be changed to a bigger one.
Then a valve has to be put in on one side. I think that once I do that those pieces of 2x4 can be taken out since the fittings will line up hopefully.

4. I know for steam radiators I had to use a spud wrench to take these things off. Is it the same for these hot water radiators.

5. Is there any tech info on this stuff somewhere?

6. I will be able to install a new circulator soon. I was wondering..should I put that circulator in first with the same piping on radiators and see how it works..then change the radiator piping to compare performance of the circulators?

icesailor

Are those 2 radiators where one was before? How are they connected? If the two radiators are connected with the pipe that runs behind, where does that go? Does it tie the two radiators together?

If so, that's really tweaked. You'll be making some changes to that. There's a history to that. Don't do anything to it until more information is provided. Like are there four pipes coming through the floor or just two?.

ww

Are those 2 radiators where one was before? YES..The original radiator cracked and these two replaced the one.



How are they connected? If the two radiators are connected with the pipe that runs behind, where does that go?

The radiators are connected with the pipe that runs behind and are connected to the lower right and left side of the radiators. You can see that better if you enlarge the photo.


Does it tie the two radiators together? Yes. The radiators are tied together with the 1/2 inch pipe.

If so, that's really tweaked. You'll be making some changes to that. There's a history to that. Don't do anything to it until more information is provided. Like are there four pipes coming through the floor or just two?. There are two pipes coming from the floor in the middle of the two radiators.

I won't touch anything on this yet...

Paul48

I think I read somewhere, that connections bottom-bottom became the preferred way of doing it years ago, because it was much easier to bleed the system.

icesailor

Paul48 said:

I think I read somewhere, that connections bottom-bottom became the preferred way of doing it years ago, because it was much easier to bleed the system.

It may be the preferred method for a single radiator, but when you connect two radiators like they are one, where there is no connection to the top, makes it so the first radiator of the two, has to get completely hot before any hot water gets to the second radiator. Then, if it is truly connected with 1/2" Copper Tube, the restriction is so high, the two radiators can never achieve their output before the rest of the radiator get hot and shut off the thermostat.

Remember about Steam Only radiators that aren't connected at the top won't work on water/hydronic systems. This is the same as a two section radiator without the top connection.

Those bushings can be removed. They MUST be removed and the end connectors need to be increased as large as possible. They MUST be connected at the top.

One radiator always gets hot before the other one starts to feel warm. Then, one is hot while the other one is getting warm. Correct?

Post some photos of the connections in the cellar that go to the radiators.

Paul48

ice......Did you participate in solo debates in school?

icesailor

Paul48 said:

ice......Did you participate in solo debates in school?

No, I didn't.

Someone wanted to know if the piping might have been causing his problem. I've seen that problem and fixed it. Is that a problem?

I never met a problem that I backed away from. I considered it a learning experience. I also seem to have a problem with situational awareness. Should I just STFU and go away?

Is it MY fault that some dubber was too stupid and lazy to put a 2' pipe wrench on those bushings, put up a 6' ladder next to the radiator and jump up and down on the wrench until it came free? Is it my fault that the same dubber thought that you could install those two radiators like that?

I've seen long radiators that were piped at one end with high flow, only heat the first three sections. I've seen the same type situation with Mono-flows in a Cellar where it either didn't work at all, or another when they fed one side high and one side low. The hot was a diagonal and the other side of the diagonal was cold.

People used to ask me. Because I didn't give a ship and I never treated anyone like they were stupid for asking me, and I learned something.

That's a problem? People come here for answers. I get more answers to questions I have than I ever answer to.

Paul48

icesailor said:

Flowing on a bias:

I don't know what the radiator manufacturers are saying but, the new "modern" radiators are usually 1 1/4" or 1 1/2" on the bottom and 1" on the top. Either way, most I see, old or new are piped with the supply and return on the bottom. In retro-fitted old houses, they were often piped on the same end because of convenience. On gravity systems where the flow is slow but the volume is high, the hot water rose diagonally from the bottom inlet and rose to the top. Where the cooler water in the radiator, being heavier that the hot, went out the bottom return. Only in grossly over pumped system did I ever see a problem where the hot water went in so fast that it beat the cold water out. People that don't understand that the water flow through a gravity system without a pump might have the same flow as a properly designed system with a pump. Many look at all that water and thing that a bigger pump will do the job better. When in fact, it will make it worse. There's very little restriction in the 1 1/4" gravity pipes but a ton of it in the 1/2" pipes. I'll bet that the circulator is grossly oversized. If it was a three speed circulator, I bet the radiators would start working if they ran the pump on the lowest speed. Or, but a 4-way mixer on it and ran the system circulator on ODR. To prove my point, open the flow check so the system runs on gravity. Disconnect power to the circulator. Set the high limit to 140 degrees and let it run. In a few hours, both those radiators will be as toasty as the rest of them. Once the temperature evens out, the system will balance out. Like when you forget to close the flow valve when you work on a system or drain the house for the winter. The customer will be calling back telling you that the house is too hot and the thermostat is satisfied. It goes along with forgetting to turn the power switch back on before you leave. Both things I have done consistently.

I made that comment, in part, because it corroborated what you said your experience was.

ww

Post some photos of the connections in the cellar that go to the radiators.

Here are some photos. The pipes range in size from 2 1/4 to 1 inch in the photos.

Let me know if you need other views.

icesailor

That's particularly bad. Trust me. A competent Piper could get those bushings out easily.

You only need to get the bushings out and pipe it with 3/4" copper tube. 1" would be best. But you have to connect the top and bottom facing outlets to at least 1" pipe (IMO) and it will work. It then "sees" the two radiators as one. When you make the system "SEE" the two radiators as one, it will work properly. As it is now, the huge restriction put in to the system will just make the flowing hot water volume never get to that radiator(s).

If there is no other load on the boiler (like hot water, an Indirect or a Tank-Less coil, and the only thing that starts it, you could add ODR and it would probably resolve itself. It wouldn't be right. But it might work.

If you start the thermostat and the burner/circulator starts, follow the hot water around and see how much slower it travels through those two pipes than the rest of the system.

It also might be effective to find a used radiator that will fit in that space but be higher or have more tubes per section.

ww

ok..thanks...the photos i posted last of all the white pipes are some of the radiators on the first floor. It looks like you are referring to the top floor...the one i'm changing is the one on the top floor...wondering on those bushings on the top floor..i guess the restriction of flow would remain if i took out the outer bushing connecting the copper pipe..and found a 1/2 inch to one inch an used a one inch pipe...?

I understand about connecting the radiators like you say..make the radiator one...why would someone do that the way it was done...not knowing anything i would have figured that was wrong.


As far as taking those bushings off if they can come off I usually get them off..I have up to 4 foot pipe wrenches, a 4 foot pipe, a hammer and penetrating oil.

Do those bushings come off using a spud wrench like the ones i took off in a steam system or not?

icesailor

You don't need a 4' pipe wrench to get the bushings out. It might help. I'd be using a 2', 3' at the most because I don't own anything larger than a 3' wrench.

See the hexagonal part on the radiator painted white? That comes out. Get a scrap piece of plywood to put on the floor. Set the radiator on the plywood to save the floor. Put a 6' step ladder beside the radiator to support your self while you jump up and down on the wrench. You don't need any heat or lubrication. Remember, you want the wrench to be pushing DOWN so you are jumping DOW to the earth. NOT lifting UP and lifting the whole radiator.

Then, there's the two plugs on the top. Two have to come out. If they have a hex head, you can try to find a 6 point socket to fit it. If it is a 4 point, yu can find 4 & 8 point sockets but not easily. Farm equipment was all square head nuts and bolts. They switched to hex heads. You used to be able to get 4 & 8 Pt sockets from Sears. Not now. You might need to drill a big hole in the plug with a metal hole saw and get a metal saw blade inside to cut down to the threads and split the plug out.

ww

thanks for the great info!

I traced the supply and return lines leading to the radiators including the upper floor in question. That's the one with no shut off valve and the one to be joined and piped.

I noticed that in some of the rooms the shut off valve is on the supply side (going out from boiler on top) and some are on the return side(to bottom of boiler)

I needed to trace all this to find out which side to put the valve and for later reference when I follow the heat circulating throughout the house through the pipes.

Which side does the valve go on?

On the top floor there are two pipes in the floor..and two pipes leading from the lower floor..I traced the left pipe leading up to be the return and the right pipe the supply. I hope that means the pipe on the floor on these same sides are the same.

Based on what I observe here the valve can be put on either side and still work? The valves I checked haven't been changed for any repair jobs by me or anyone I know of.

icesailor

Personally, I don't think it is a game changer where the valves go. Especially if you feed through the bottom.

Measure the two pipes as they rise out of the floor. Are they the same height? The lower one is probably the side with the valve. Measure the heights of other radiators and see if there is a difference. And which ones have the valve.

I have always found that when I didn't know how something had been done, I looked around for an example of how some old dead guy did it. They can still teach a lot while taking their dirt nap.

ww

Thanks. That's just what I did..walked around and looked...the dead men speak to us through their work.

icesailor

It must have worked once, or they would have fixed it. If it was once working, what did someone do to it to make it stop working?

If you have an idea how the old dead guys did it, you become smarter.

ww

ok..used a 6point impact socket,breaker bar and pipe...no problem getting this off.

icesailor

You Da man!!!!.

See how easy those came out? The bushings will be just as easy. Now, you're one pay grade ahead of the guys that installed the radiators that thought the bushings were part of the radiator.

ww

yes indeed...i got around to working on that again..and all the bushings are taken out, the old pipes gone. Now I'm going to make one radiator out of the two...instead of using unions between them does anyone know where I can get a kit that has right and left threaded bushings and tool to join them together with a thin gasket between them?

ww

I came across this excerpt from an article on old radiators..I should have figured that Dan would have an answer for my question..and here it is..maybe the tapered ones will work since there is a threaded rod on the radiators I'm working on...


So be prepared for a setback or two.
The best explanation I found of how radiators are assembled comes from Dan Holohan, a writer with an unusual interest in steam heating systems. He and his wife maintain a website (www.heatinghelp.com) with all kinds of information on the subject, plus a lot of other interesting stuff. Dan also has written a book on the topic.
Dan says there are two types of nipples that join radiator sections. One has right-handed threads on one end and left-handed threads on the other. When the manufacturer turned the nipple, it would draw two radiator sections tightly together.
While ingenius, this design had a serious flaw. After a few years of use, the nipples corroded into an immovable blob of metal that you can't take apart. Further, no one makes replacement nipples of this type. If you were lucky enough to get sections apart, you would never be able to get them back together.
The other type of nipple has no threads. These are tapered connections that form a tight seal as forced is applied with a threaded rod and a nut. Logically enough, they're called push nipples and, because your radiators are held together with a rod and nut, that's what you're dealing with.
Theoretically, you should be able to loosen the big nut on the end and then force the sections apart with a pry bar or some wooden wedges. Applying heat or a penetrating thread lubricant would probably help, and you might indeed need a breaker bar to loosen the nut.

icesailor

The above will work if the two radiators are exactly the same. But you don't go about it like you mentioned what you are hoping to do. And if the radiators are old enough to have threaded nipples joining them, don't even bother trying to modify them. I'll do anything. I'd be stopping at that.

If you are going to try to make the radiator onto a big one out of two smaller ones, you only take the right or left end section with legs off of each radiator. Then, off of one radiator, remove as many intermediate sections as you need to get the R or L end leg section back on. Bottom nipples are all 1 1/4". Some Modern radiators have 1" top nipples. You can tell if the upper plug measures around 1 1/4". It will be a 1" push nipple. If the plug is around 1 1/2", it is a 1 1/4" push nipple. If you take the 1 1/4" bushing you took out of the bottom and compare the plug in the top, it should appear that it would fit. You will need the proper push nipples. You then need to get the old nipples out of any section you are going to use over out to be replaced by new ones. You need to lay the radiators down on their sides on a piece of plywood and split them apart. You must remove the draw rods. You will need new ones. You will have to cut and thread them for the proper length. They split apart easily when you carefully put a fat wedge between the sections and carefully hit it with a heavy hammer. Any push nipples you need out are easily removed with a 18" pipe wrench and spinning them out. Don't try to cut them out. You might be sorry. Then, you have to very thoroughly clean the machined surfaces where the nipples go. You need to get all paint off the surfaces so there is no interference. Carefully sand with fine sand cloth, the black preservative off the push nipple and with a brand new can of pipe dope, paint the surface of the nipple and the inside of the section, Insert the nipple and carefully align it. If it is cocked, it will be ruined and you might destroy the mating surfaces. Slide the sections together, mating the push nipples in their proper holes. Take the threaded rod and thread it through the radiator and engage the nuts to the properly cut and threaded lengths of rod. Tighten the rods as far as reason. Then, you have to put something like a 2'X6" against the end section and whack the 2" x 6" with a 10# top mall to push it together. Not too hard. As it goes together (if it goes together) tighten the threaded draw rods. If you get it together so that the pipe dope squeezes out from between the two sections, you're home free (hopefully).

Simplify though, I'd live with the two radiators connected together in a proper way, kick some grass on it and be on my way. They would probably work together if they were just piped together with 3/4" Copper.

If you're really serious, and you lived close to New Bedford, MA, you could see if my old wholesaler would split and make up your radiator for you. They make up any size radiator that you might need that isn't a standard size. We often sent them radiators from frozen up houses and they would test, replace and test again the repaired radiators if they were modern and stock radiators. For a fee of course. They are set up to do this because it is a really old company and they used to make radiators for the old dead guys. They have hydraulic presses to push them together. You have all the sections you need to do it. You might end up with a radiator that is a smaller output than the original one. Measure around with the old ones and find one that has the same distance between the pipes. Tell us and we can tell you what the output of the radiator was. And what a new one is. If you leave the two connected and improve the connection, you can put a TRV on it and have better control of the heat in the room. I find that it is never too hot for the ladies in the winter in a room. Especially if they have thyroid issues and their temperature regulators are on the fritz.

ww

ok..thanks for the info...i'll think on this one..either with the nipples as explained or at the least using either a union in between with nipples or a left/ right threaded nipple..i'll see what's available around here. thanks