Radiator not working

Jen_8

I was wondering if someone could answer a question for me before I call in the pro's. I have been living in an old home for @ 3 years now and it has a one pipe steam heating system. One of the radiators just stopped working. Up until this year there was always extremely loud water hammer going on in what seemed to be the main pipe leading to that radiator (can't recall if it was at the end of the cycle, middle, etc.) It also happens to be the furthest from the boiler. Now, no steam reaches the radiator and there is no water hammer. Is it likely that there is a clogged pipe? Or, in my wishful thinking, could this be remedied by making sure there is enough pitch for the condesate to return to the return pipe?
Please forgive my ignorance and thank you for any advice.

Al Hendrickson_21

Vent

I'm not a pro heating guy . . . just a lowly engineer with a boiler in his house.

Without looking at it it's hard to tell. (The valve at the base of the radiator is wide open, right?) I doubt that it's a clogged pipe. Steam pipes are comparitively huge. The first thing I'd look at for the no-heat condition is the radiator vent, the small silver thing halfway up the radiator at the opposite end from where the steam comes in. If the air can't get out, steam can't get in. It should be inexpensive and easy enough to replace yourself.

Water hammer is probably related to the pitch of the pipe, or the pitch of the radiator. . . . or could result if the valve to the radiator wasn't all the way open, or had fallen apart inside, leading to a partial blockage. The radiator valve on a single pipe steam radiator needs to be all the way open so the steam coming in and the water going out can pass each other without colliding. In fact, just about all watter hammer in single pipe systems is caused by steam and condensed water colliding. If you keep things such that water can't puddle in the pipe on the way back to the boiler, it should be very quiet.

If you don't have Dan Holohan's book "We Got Steam Heat," I'd recommend getting it. If nothing else, it would help you communicate with whoever services your system.

Jen_8

Thanks Al -

Yes, the valve is all the way open. However, I had the same problem last year with no heat coming from the radiator and found that the valve was closed for some reason, most likely my son playing around. I opened the valve and still nothing. With some advice from friends, I temporarily fixed the problem by replacing the vent and slightly tapping around the valve (figuring maybe the valve broke inside and partially clogged). It's nice to hear you do not think it is a blockage in the pipe. Taking all of this into consideration, it sounds as if the valve may be broken and/or there is a blockage there. If I want to take one step at a time and determine the valve is not broken inside, what would you recommend? Is this something, with a little help from someone, worth taking a shot to look at and/or replace?

nicholas bonham-carter

non-working rad

1.heed the advice from al.
2.do buy the book
3.read up on how to correct improper pitch in the rad.[i suspect if the vent can be removed and blown through[boiler off!], then the floor may have settled, causing a puddle in the pipe; which steam cannot get through.--nbc

Big Ed_4

Plugged return ?

vent is clear ,valve open ? Since it is the last radiator the condensate could be backing up for some reason. Plugged wet return , water level too high , pluged or gauge glass shut off and you keep adding water.

Remove the main vent on the main see if water is backing up.

I have seen risers that was plugged . Open valve see if you can drain water down .

But there was a hammer but heat , now no hammer and no heat and this is the last radiator ? My guess condensate is blocking main vent and that riser .

Jen_8

Hey Big Ed...yes there was a really loud hammer but heat, now no hammer no heat. I just had the boiler serviced about 4 weeks ago, as I do every year, and they replaced the shut off valve b/c it was clogged. I have already released some water and refilled with just enough water. However, I did notice that the water level sank quite a bit especially with the boiler not firing up very often, yet.

By the way, great forum and I can't wait to read the book "we got steam heat". I read the sample pages and can't wait to learn more.

Unknown

Jen-
What are you referring to as "the shutoff valve"?

All of the advice above is good. I also have an old house (200+ years) and was having problems with a radiator that I thought was pitched correctly. It had little blocks under the feet on one end so it sloped towards the inlet pipe. It took me a while to figure out that the whole house had sagged and while it visually looked okay, the radiator was actually sloping the wrong way. You need to check your radiators with a carpenter's bubble level. If you don't have one I'm sure you neighbor has one you could borrow. While it is possible that your inlet valve is broken they're normally pretty sturdy so the probability of being broken is low. You just want to make sure it is fully open. On a one pipe system, the radiator valves are either fully open or fully closed. I "exercise" mine a couple of times a year, by opening and closing them a couple of times just to keep them from freezing up.

I'd just wait for Dan's books to arrive. After reading them you'll soon understand about steam and most likely know more than the guys now servicing your boiler. In my experience most of the service guys are "burner" men and have very little understanding of how steam actually works. Once you read the book and understand it a bit, put on your old clothes, get a flashlight and explore your steam system. Think of yourself as a water molecule leaving the boiler in the form of steam and trace your path though the system. Trace the mains, find the main vents, the dry and wet returns. All these are explained in Dan's book and with his easy to understand commentary everything falls into place very quickly.
Learning about your steam system will allow you to make minor repairs yourself and will give you the knowledge on what needs to be done if you decide to get someone else to do work on your system. If nothing else it will allow you to qualify who is competent to work on your system and who is not.