radiator flush?

Hollis

Previous  tenant says only half the rad is heating,.Its the highest  apt in the building. The .Apt is empty for a few days and was thinking about  trying to flush it,..it is on the 4th floor and don't relish carrying it down all those narrow stairs and I understand that it can damage the pins ect.



So is there a way? Wondering if I can fashion  some piping that I can attach a hose from the kitchen facet. to the radiator ,..However I also wonder if that will dislodge enough gunk to and have it flow out the steam valve out to a drain,..



Any other ideas?

icesailor

Half Cold Radiator:

"Any Other ideas?"

Sure. Is there enough pressure in your system to get the water to the top of the radiator on the top floor?

One pound of water pressure on a gauge (1# PSIG) supports a column of water 2.31" high. If you have 10# PSIG on the pressure gauge, the water will be 23' high in the system above the gauge. Not the floor, not the ceiling, but the gauge. If you have a radiator that the bottom of the radiator is more than 23' above the gauge, there will be no water in it. If, the 23' mark comes to half way up the radiator, the radiator will work "Half". The bottom 1/2 will work and the top half will be cold.

Flushing it out may work for you. It's not ever worked for me under the circumstances you describe. If it doesn't work (flushing), try checking the pressure and if it isn't high enough, raise the system pressure.

Because I am mathematically challenged, I figure 8' for a cellar and 10' per floor. Plus the height to the top of the radiator on the top floor. Plus, fudge.

You with four floors are talking over 20# PSIG.

Hope this helps.

Rod

Radiator Flushing

Hi- I flushed my radiators in place by disconnecting them and hooking up a wet /dry vacuum to the inlet spud pipe using an assortment of fittings and duct tape. (Be sure to have a pan ready to catch any water when you loosen the connection between the valve and the radiator)

 I then elevated the opposite end of the radiator about 6 inches so any crud in the bottom of the radiator would flow towards the inlet pipe. I following this up with a hose connected to the vent hole (more assortment of fittings) so that I could introduce a little water to help with the flushing. I must warn you that there is a high possibility of some leaking and spills during the flushing operation, so take adequate precautions.

 From a flushing standpoint while the foregoing setup worked rather well, I really question the overall benefit of the flushing as the radiators, in general, were surprising clean inside even though they hadn't been opened in 85 + years.

 Since it sounds like the "problem" radiator is one of the furthest away from the boiler, the half heating may be more of a venting problem than an internal dirt problem. Before going through the efforts of flushing the radiator, you might want to try a more aggressive vent, like a Gorton Size "D" and see if that makes any improvement.

What type and model # is the vent now?

- Rod

icesailor

Flush:

SOmehow, I understood that this is a hydronic forced hot water system. If so, what I said before applies. If it is a steam system, what Joe says may apply though as you describe the radiator getting only half hot, it sounds to me like it is a radiator that the pressure in the system isn't pushing the water up high enough in the system. If it is steam, system pressure has nothing to do with how high the pressure in the system gets. But the radiator getting only half hot would seem to preclude it being steam. It either works or it doesn't. A radiator on the top floor not working is more likely a hot water hydronic radiator rather than steam.

We both agree (Joe and I) that flushing your radiator will probably not solve your problem. Are there coil vents or squared key nebts on the top of the radiator or a can vent on the side? Are there any vents at all on the radiators. If coin vents to bleed the air and you don't get any air, you need more pressure in the system. If you have a vent on the side of the radiator, well below the top and only one pipe going into the radiator, it is steam and you have other problems, best left to a steam pro. It's been screwed up for a long time.

Hollis

definitely steam radiator

Ice sailor, Its definitely steam. I THINK its getting enough pressure as the Gorton D vent has a bit of air flow that you can feel coming out of it.



Rod,..well yes,..I really don't relish the mess it might make,..I didn't consider the wet vac though,..not sure how radiators are made,...in the bottom,..is it a straight thru , that is can you run a hose extension from the bottom spud and get to the other end of the radiator to start  with much removal first?

crash2009

Maybe

 that radiator needs more venting.  Here is a photo of a technique called master venting.

Rod

Balancing

The standard cast iron steam radiators come in two basic types. The older style that were for steam only and the newer style that can be used for steam and hot water. The older style's sections are only joined across the bottom of the radiator . The new style's sections are joined across both the top and bottom of the radiator. (See attached drawing)

Thinking it over, I rather doubt your "problem" radiator needs flushing as I think you may have more of a steam distribution problem than a dirty radiator. By definition steam radiators are constantly be "steam cleaned" so tend to stay fairly clean anyway. I flushed mine but quite frankly they really didn't need it.

 You mentioned that you already have a Gorton "D" on the "problem" radiator, what size vents do you have on the other radiators? Keep in mind the steam adage: "Vent your mains fast (large capacity venting) and your radiators slowly! " (not over vented) It maybe that if the other radiators on the system have large capacity vents, that they are "hogging" all the steam available so that very little is left for the furthest radiator. Typically this is what happens. Once the "hog" radiators heat up, the steam condensing in them slows down and which makes more steam available for the "problem" radiator. The problem then is the thermostat (located in a room with one of the "hog" radiators) shuts off before the problem radiator has a chance to fill with steam.  Solution: Large capacity main vents and lower the venting capacity of the "hog" radiators.

Keep in mind I know very little about your system so I maybe completely wrong about your venting capacity. I just think this scenario is much more a likely cause than a dirty radiator.  You could try a master vent as Crash has suggested though if there isn't enough steam available due to "hogging", this won't do much good. Flushing radiators isn't fun and since the benefit is questionable I 'd try other options first.

- Rod

icesailor

Steam Radiators:

I feel a consensus that flushing radiators may not solve your problem.

I'm not a steam expert in any way shape or form. But, it is possible that your boiler isn't large enough to handle all the radiators. The radiator output needs to be calculated to see if you have a boiler big enough to make enough steam. The steam venting seems to be the biggest problem with these systems. You need someone who can really get into your system that knows what they are doing. You need that professional that isn't just a heating professional, you need the one that has steam not as a job but a life. With a brain that "sees" how the steam wants to go and what will make it not want to go where you want it to and why. There aren't a lot out there. Sounds like a couple are helping you.

Jamie Hall

Don't bother...

a steam radiator would have to be unbelievably crudded up before it stopped heating -- and then it would make all sorts of odd unfortunate digestive noises.  If this is one pipe steam (not clear, but most likely) it's as a couple of the guys have said -- it's either inadequate venting on this radiator, coupled with perhaps overenthusiastic venting on some of the others, or just plain not enough capacity in the boiler, or the boiler shutting down before the radiator has a chance to get fully hot because the thermostat is in an area which heats rather quickly.

crash2009

Forget the flush

  As you know, tenants are notorius for giving bad information.  "It was like that", "I'll pay you tomorrow" etc.  Most of the time their reports are intended to side-track the landlord.  Its human nature, some of them have been doing it for so long, they don't even know they are doing it.

To begin with, I think it is normal for a rad to be half hot at times.  Mine are half hot most of the winter.  The only time they get hot all the way across is when its very cold, or when a window is left open. 

I have a few questions that might help us give you a better answer.

1-Has there been any no-heat complaints?

2-If you have felt this half hot radiator, which half was hot?  one and two? two and four?  some other combination?

3-Has there been any too hot, or too cold, complaints from the other tenants?

4-If you live in the building, how is your heat?