Converting from steam to hot water heat

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Converting from steam to hot water heat

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AntGray13

Ready to do my steam to hot water conversion now! Thanks Dan... (tongue in cheek)

nicholas bonham-carter

Jumping from the frying pan into the fire!--NBC

Steamhead

Why would anyone do this?

ChrisJ

Steamhead said:

Why would anyone do this?

I know why and so do you.

Steamhead

All together now...................

jumper

I think Europe banned steam heat. Available was a concentric fitting that provided a one pipe radiator with two connections. Had to run a supply that would go into inner pipe of fitting which went length of radiator. The return could be original steam pipe. Instead of air vents one could evacuate air and then fill with degassed water. I suppose contraption could work because warm water rises?

Steamhead

No, they didn't "ban" it- they rebuilt after the war and happened to use hot-water. I don't know why. Then, all their research went into hot-water.

jumper

Steamhead said:

No, they didn't "ban" it- they rebuilt after the war and happened to use hot-water. I don't know why. Then, all their research went into hot-water.

I think it was in Belgium that I saw those two into one gizmos. Sounds like a difficult way to happen to use hot water.So maybe ChrisJ will tell me why?

ChrisJ

jumper said:

Steamhead said:

No, they didn't "ban" it- they rebuilt after the war and happened to use hot-water. I don't know why. Then, all their research went into hot-water.

I think it was in Belgium that I saw those two into one gizmos. Sounds like a difficult way to happen to use hot water.So maybe ChrisJ will tell me why?

Why did I get dragged into this?
Since I did, my answer would be ignorance is the reason why.

I am, and will always be a fan of transferring heat with phase change whether it's my house or my refrigerator.

BobC

This offers a plausible explanation -

http://diy.stackexchange.com/questions/10506/why-are-steam-radiators-used-in-the-usa

Bob

Steamhead

jumper said:

I think it was in Belgium that I saw those two into one gizmos. Sounds like a difficult way to happen to use hot water.So maybe ChrisJ will tell me why?

Might have made the piping easier to install. They did the same here around the turn of the 20th century with those "Unique" radiator valves.

Dean_7

I have a friend who converted his steam system to hot water. He lost power for 4 days in the recent storms we have had . System froze now has 6 of 9 radiators broken plus a mess. just something to think about.

JUGHNE

These pictures were posted previously. This used to be a steam system as evidenced by the trap. It is now (was) a hot water system. Three floors of damage.

jumper

Dean said:

I have a friend who converted his steam system to hot water. He lost power for 4 days in the recent storms we have had . System froze now has 6 of 9 radiators broken plus a mess. just something to think about.

Say it again. In former USSR there now many apartment blocks with broken HHW. Each winter somewhere power is out too long and HHW is at risk. StormSandy saw people with generators out of luck because modern heating appliances don't like small generator's output.No heat is bad enough without having to consider draining hydronics. And re-filling can be frustrating.

Dean's friend made a serious mistake.

tlowc34

I've read everyone's comments. But I'm still considering the conversion to hot water and I wanted to get the opinion of the group. I figured it would make the most sense to give some info on my house, then info on my current system, then the pros of switching to hot water, pros of staying with steam.
1. My House:

• 1929 Prairie School Style Arts & Crafts Colonial
  
• 3,330 Sq.Ft. First and Second Floor
  
• 1,600 Sq.Ft. Basement (formerly finished)
  
• 1,200 Sq.Ft. Attic (currently unfinished)
  

2. My System

• 2009 Natural Gas Boiler
  
• 2 Pipe Steam Heat System
  
• Cast iron tube type radiators (have the 'flats' cast in for bleed valves, but weren't drilled and tapped since they weren't needed)
  
• Sealed asbestos on exposed plumbing in basement
  
• Radiators were sized for walls without insulation (in 1929). Previous owner had insulation blow-in (1980s)
  

3. Pros of Switching to Hot Water

• Ability to add a zone more easily for the attic (not currently heated, but plan to)
  
• Ability to relocate basement radiators from the ceiling to the wall, near the floor (cause I've hear heat rises, duh!)
  
• Ability to get rid of all those damned sloping condensate runs that KILL overhead space in the basement. I'm 6'4" and with the length of the runs the necessary drop makes for a visual eyesore and an obstruction in the basement. With hot water, I could rerun these in PEX or Copper inside the joist bay, with no slope, and remove all of the asbetos (following strict abatement procedures of course).
  
• Ability to add radiant floor heating systems
  
• Ability to regulate/schedule temperature on a room by room basis from a single control unit and in room (fussy wife)
  
• Safer (lower) radiator surface temperature (2 yr old & newborn in the house)
  
• (this is a working theory I have) Due to the specific heat of water, the heating system plumbing will maintain a more consistent temperature rather than cycling 68 degrees while off to 212 degrees while on, which causes lots of noise with the expansion and contraction of pipes that are laying in joists between floors. Rather than the steam system firing up and running for 20 minutes and getting boiling hot, my hot water system may run for 60 minutes but the system might not even get up to 120 degrees before the system had given enough heat to the rooms to bring the temperature up enough to turn off the system. Then the slow heat loss of the system (because water has a greater specific heat than air/steam) might only drop the system to 100 degrees before another call for heat
  

4. Pros of Staying with Steam

• Reduced cost (not paying to upgrade)
  
• System can't freeze
  
• No pumps to replace periodically
  
• ????
  

Really interested to hear the opinion of the group.

Thanks,
Todd

Steamhead

Sounds like you have a Vapor system. Vapor was the Cadillac of heating in its day and is still one of the best out there. Have you noticed any manufacturer's name on the original valves, traps etc?

You can "zone" a Vapor system room-by-room, by installing thermostatic radiator valves everywhere but the area with the thermostat.

If you put a reflector of aluminum foil or similar above those basement radiators, they will reflect heat downward.

It should be just as easy to run steam and return pipes to the attic as it would be to run hot-water pipes. If not, you can use a heat exchanger on a steam boiler to provide hot water for that zone. Or, if the house is not too tall, you can run a hot-water loop directly from the bottom of the boiler.

Remember that while a steam system runs at 2 pounds or less- much less on Vapor- a hot-water system needs at least ten times that pressure. This WILL do a great job of finding weak points, which will show up as leaks.

Keep the steam.

tlowc34

I believe it to be a Vapor system as well, based on the high/low arrangement of the pipes as they enter and exit the radiator. The traps/valves are all branded Trane. Most have silver tops, but several have green labels and are marked 'B-2'. In my research on Vapor systems, it looks like they aren't supposed to have vents, however several of my radiators do have vents. Do you think these were (incorrectly) added in the past 80+ years to remedy problems with balancing heat between rooms after insulation was added to the walls?

Jamie Hall

tlowc34 said:

3. Pros of Switching to Hot Water

• Ability to add a zone more easily for the attic (not currently heated, but plan to)
  As @Steamhead noted, there are at least three ways to do this with the current steam system. Each has advantages and disadvantages. The work would be more or less the same as with a new hot water system, so this item should not be a factor.
  
• Ability to relocate basement radiators from the ceiling to the wall, near the floor (cause I've hear heat rises, duh!)
  Again, as has been noted, just putting reflectors in would make some difference. However, much of the heat from the radiators is convected -- and the convection works whether the radiator is high or low on the wall.
  
• Ability to get rid of all those damned sloping condensate runs that KILL overhead space in the basement. I'm 6'4" and with the length of the runs the necessary drop makes for a visual eyesore and an obstruction in the basement. With hot water, I could rerun these in PEX or Copper inside the joist bay, with no slope, and remove all of the asbetos (following strict abatement procedures of course).
  This can be a significant point. However, it may be that the pipes can be rerouted to be less of a problem.
  
• Ability to add radiant floor heating systems
  Not a problem. This can be added off a steam system just as easily as off a hot water system.
  
• Ability to regulate/schedule temperature on a room by room basis from a single control unit and in room (fussy wife)
  If this really was a vapour system, as it appears to be, thermostatic control valves can be added for room to room control.
  
• Safer (lower) radiator surface temperature (2 yr old & newborn in the house)
  If this really is a problem -- and I would wonder about it, but then my kids grew up with steam heat and wood stoves and survived, so I may be biased -- enclosures can be created with little loss. I would note that even a hot water radiator is hot enough to cause a very nasty burn...
  
• (this is a working theory I have) Due to the specific heat of water, the heating system plumbing will maintain a more consistent temperature rather than cycling 68 degrees while off to 212 degrees while on, which causes lots of noise with the expansion and contraction of pipes that are laying in joists between floors. Rather than the steam system firing up and running for 20 minutes and getting boiling hot, my hot water system may run for 60 minutes but the system might not even get up to 120 degrees before the system had given enough heat to the rooms to bring the temperature up enough to turn off the system. Then the slow heat loss of the system (because water has a greater specific heat than air/steam) might only drop the system to 100 degrees before another call for heat
  The expansion and contraction of pipes is something to consider, but if the pipes are properly suspended the system should be noiseless or very nearly so. Your point about thermal inertia -- mass -- is well taken, but in your system a large chunk of that mass is in the radiators, which wouldn't change. Depending on how fussy you need or want to be, steam systems can be controlled rather easily to minimize changes in the metal temperatures (it's related to the on/off times of the system). I might note that even with the added insulation in the house it's unlikely that you could get away with 120 degree water heat during the colder months, though you might manage with 160 in and a delta T of 20.
  

4. Pros of Staying with Steam

• Reduced cost (not paying to upgrade)
  
• System can't freeze
  
• No pumps to replace periodically
  
• ????
  Much lower cost. Dead simple. Reliable. Quiet, if done properly.
  

Really interested to hear the opinion of the group.

My two cents worth...

Thanks,
Todd

Steamhead

tlowc34 said:

I believe it to be a Vapor system as well, based on the high/low arrangement of the pipes as they enter and exit the radiator. The traps/valves are all branded Trane. Most have silver tops, but several have green labels and are marked 'B-2'. In my research on Vapor systems, it looks like they aren't supposed to have vents, however several of my radiators do have vents. Do you think these were (incorrectly) added in the past 80+ years to remedy problems with balancing heat between rooms after insulation was added to the walls?

That's a Trane Vapor system. It should not have any vents on the radiators. There should be vents on the ends of the steam mains, as well as one or two on the dry (overhead) return near the boiler.

If any of these vents, or the radiator traps, aren't working, you'll have steam distribution problems.

Charlie from wmass

Heat does not rise. Hot goes to cold. If Heat did not go to cold you could not broil a steak.

tlowc34

Yes, I understand this from a thermodynamics standpoint.

However everything being equal temperature around the radiator, if the radiator is on the ceiling in the basement - is it doing a better job heating the air, joists, and floor above it or the air below it?

Charlie from wmass

It's doing a better job heating below it because warm air rises and the heat from the radiator wants to reach the cool floor

ChrisJ

Let's not forget radiators are only 30% or so convective.
60% of it's heat output is line of sight via infrared output. You'll feel that below it far more than you'll feel warm through the floor above it as will any objects in the room.

Abracadabra

Charlie from wmass said:

It's doing a better job heating below it because warm air rises and the heat from the radiator wants to reach the cool floor

Wait.. what?

Charlie from wmass

Read it again. You will get it.

Jamie Hall

In case you don't ( @Charlie from wmass , I think you may be an optimist), what happens from a high wall or ceiling radiator is the warm air rises and spreads out across the ceiling. Cools a little, and starts to drop and eventually gets to the floor. That rising warm air is replaced by cooler air coming up from the floor. Works just fine.

Charlie from wmass

The infrared does not care much about the gravity.

Jamie Hall

Charlie from wmass said:

The infrared does not care much about the gravity.

So true. The ceiling mounted radiator -- large -- at the south end (entrance) of the basement does a dandy job of keeping the whole laundry area nice and warm!

hboogz

@Jamie Hall do you happen to have a pic of this rad setup? Would like to accomplish something similar.

Thanks.

Harry

Jamie Hall

hboogz said:

@Jamie Hall do you happen to have a pic of this rad setup? Would like to accomplish something similar.



Thanks.



Harry

I don't have a picture -- if I get to it, I can post one... it's basically a single column radiator, about 4 feet long and perhaps 30 inches wide (tall, if it were like a normal radiator!). Feed is at one corner, and the outlet is at the diagonal opposite corner. It's slightly tipped towards the outlet -- but not much. Whole thing suspended from the ceiling. EDR is about 50. There are actually two of them in the system -- the other is in the far north end. They serve partly as radiators, but also as condensers for "excess" steam.

hboogz

@Jamie Hall dude that sounds wicked. Would love to see a pic to see how it's mounted, if and when you can. My minds eye is not quite visualing this one.

Harry.

tlowc34

Here's my setup

Jamie Hall

Very like mine.

hboogz

That's awesome!!! @tlowc34 this is single pipe steam? Or is this two pipe with the return piped into the wet return of the boiler ? It's mounted with threaded rods from the beams?

hboogz

What's the technical term for these rads? Can I get these at supply houses you think? Or is it a craigslist search and pray ?

tlowc34

It is a two pipe vapor system, return is piped into the return loop for all of the condensate (wet?). The mounts are a little funky, they are radiator surface mounts that you would use if the same radiator was strapped to a wall however they are strapped like a pipe against the joist and then hung down below. Does that make sense?

Steamhead

(dry.)

hboogz

Is it safe to presume this can be done with a single pipe parralell flow system with access to the wet returns if I piped a ceiling mounted radiator two-pipe with the return piped into the wet return before it meets the Hartford loop?

Danny Scully

Yes @hboogz, it can be done and you might even be able to keep it 1-pipe if you can get the pitch.

Charlie from wmass

If a radiator can not be found it can be made from pipe.