Replace radiator in a tiny room with a riser?

pgf

The half bath in our house is less than 20 sq ft. The house has single pipe steam.

The 5 section radiator in that room is only 23" tall., but when operated normally, it makes the room much too hot. Turning the steam valve off makes the room too cold. So as a compromise, years ago I blocked the steam vent (just a layer or two of teflon tape across the vent's opening, before screwing it in) so that steam can arrive into the radiator, but not go anywhere. Basically the radiator is heating using convection/conduction transfer from the supply pipe. That works pretty well, and keeps the tiny room comfortable.




An upcoming toilet replacement is going to use up an extra 3" of floor space in front of the toilet, bringing a user that much closer to the radiator. Too close for comfort, I believe. (Not because the radiator gets excessively hot -- there just won't be room for one's feet!)

The supply for the radiator is in the very corner of the room. It seems to me that we could remove the radiator, replace the right angle steam valve with a straight version (?), and install a simple riser going up the corner of the room. Given our past experience, installing a vent on that riser would be optional. Does this idea make sense?

paul

ethicalpaul

Sure, try it, but I would think with the much smaller amount of radiation from just a pipe you will probably want a vent on it so that it fills with steam faster.

pgf

Good point about the vent, thanks. Can that be installed on top of the riser, or do all radiator vents assume a side mount? (Newbie question, I'm sure.) I'd like to minimize fittings, for aesthetic purposes. (Suggestons for "pretty" pipe fittings welcomed! )

For the steam valve, are straight pipe-to-pipe steam valves available? Or is that just a "regular" valve at that point? I assume I need to have a valve, though I've never had much use for the steam valve in any of the other rooms.

I won't be doing this work myself, but I'd rather have some knowledge beforehand, so I can help guide the solution. The plumber might or might not be terribly steam-savvy -- he's my contractor's choice, and will be there primarily for the new toilet bend (messy job -- replacing a lead bend) and toilet.

paul

dabrakeman

You have an EDR of about 10sqft with that radiator currently. Your EDR for pipe (yes, you would want a vent at the top of the pipe) would be = ((pi * actual pipe diameter in inches * 12) / 144) * total feet of pipe. Don't know what size pipe you have but if the diameter were say 1.3" then 6 feet of it would be an EDR of about 2sqft.

If appealing to you it might be an opportunity to find something unique and attractive such as a vintage wall unit you could sand blast and paint and make look real nice and be out of the way. A typical ~1'x2' vintage wall unit has an EDR of about 7sqft. Smaller ones are to be found with lower EDR's. Look on the internet you may be able to find something on EBay or Marketplace in your area or even something shippable. Could always put a slow or adjustable vent on it like the Ventrite 1A. Could be something fun or a PITA depending upon your perspective

pgf

Okay, that's a compelling EDR calculation. Thank you for that. I knew it was worth talking about this here.

Can you point me at an image of the kind of vintage wall radiator you're picturing? I'm certainly willing to think about that. Nothing like that has come up in my searches.

Needless to say, the last thing I want to do is end up with a bathroom that's too cold!

dabrakeman

Couple examples here in 2 minute ebay search. Don't know where you are at?

ethicalpaul

The vents that I use (Maid O Mist and Gorton) come in 90 degree as well as "straight" versions. You could use either one.

With a 90 degree vent you would get a reducing elbow from your pipe size to 1/8" or 1/4" depending on the vent you get (I think both of those vents also come in 1/8" or 1/4" but that's from memory).

With a straight vent you would use a standard reducing fitting in the same way.

I'd get the stuff from supplyhouse.com but your contractor will get them wherever he or she gets them.

But don't let them buy the vents at a big box store, those are not to be trusted.

Here's an example. The reason you might like 1/4" better is that it's a less drastic reduction from your pipe size: https://www.supplyhouse.com/Jacobus-Maid-O-Mist-J5S4-5-1-4-Straight-Air-Valve-7863000-p

This is a number 5 vent, but the cool thing about Maid O Mist is you can convert it to larger capacity by swapping out (or drilling) the screw-on orifice on the top.

pgf

Thank you both! I understand both the radiator suggestion and the vent fitting better now.

Tommi68

Look at a modern steam warmed towel bar. Much lower EDR that a rad, and useful. 

AdmiralYoda

I'd personally prefer a wall mounted thin, single tube radiator. But a single pipe running the height of the wall would work too.

Perhaps you could do a heat loss calculation on that room and see how many btu's you actually need, then convert that to EDR.

Runtal's SteamView can be installed so that it is only 2.5" from the wall.
https://runtalnorthamerica.com/steam/

Castrads sells cast iron ones that are pretty compact too. This one is only 2.8" deep and has an EDR of 3.74.
https://castrads.com/us/product/mercury-2-column-18in-4-sections/#choose-palette

KC_Jones

https://forum.heatinghelp.com/discussion/151994/new-steam-mini-tube-installation-in-ohio/p1

If you look at gerry gill second post, he did something custom for a small bathroom. Cool install if you ask me.