float valve in series with VariValve?

danb2

Hi:

I wanted to get a VariValve vent, but I think there's a lot of water in the system (because I get hammering sounds, and have experienced a lot of water coming out of old, failed vents, on all 3 of my radiators, which are on the 2nd floor of a 3-story, 6-unit building), and I read in another thread that these don't have floats.

(The latest vent that spilled was a Jacobus with a #4 port.) The building management is unresponsive these days but I think a repair person said something like that there's nothing that can be done about the water - it's an old building. I like the VariValve, because Heat-Timer advertises that the flow rate can be set up to 0.72 CFM, while the next fastest one I know of, Gorton #D, does about 0.45 CFM. I have a Jacobus with a #D port on one small radiator and feel that it would be best to be able to go a lot higher, on a very long radiator that's in a colder room.

Screwing off the port doesn't look like it would be a lot faster than a Gorton #D, because down the Jacobus opening it doesn't look bigger than its #D port opening, and I haven't found test results for Jacobus. So I had the idea of somehow having a float valve in series with a VariValve. I didn't find one on the Web, so I wonder if anyone knows of any float valves that don't constrict air flow more than the VariValve.

danb2

Or, I suppose, I can have an even greater flow rate with two #D vents connected to a Y adapter, or a Gorton #2 connected to a 1/2" M to 1/8" F adapter and a right angle one, and using a TRV if necessary.

nicholas bonham-carter

Are your main vents adequate? Often using a larger radiator vent will cause the steam to hit the vent and shut it before the radiator has been filled.--NBC

ChrisJ

Likely the reason you're getting spitting is you're trying to vent radiators with vents that are too fast.

Does the bottom of the radiator heat before the top?

Can you share pictures of these radiators with us?

danb2

I'm not sure whether the main vents are adequate, as they are in a basement unit. I do often get air coming out (more often than the heating cycles). That's interesting about the larger vents. Also, in a video linked to from here it's said that Gorton No. 2 Air Eliminators close at a much lower temperature than the other ones he describes, like around 130F. I don't know if that would apply to their Equalizing Valves. It doesn't seem like it, feeling one of my radiators that has a Gorton on it (the red one, which has a Gorton #6 on it).

The last radiator that emitted water - which was more like pouring than mere spitting - had a #4 (Jacobus) on it (the smaller white radiator), so it doesn't seem likely that that was too fast. It now has a Jacobus #D on it, and it's not spitting any liquid. Looking at the vents on my other radiators, I don't think too fast ones would have been put on them, by the last owner who would have installed them. (The only failed vent I have is the #4 that I mentioned. The only ones installed since he sold the building are the #D that I mentioned, that I just installed, and the current one on the big radiator.) In all 3 cases, a large amount of water was coming out.

I'll have to check whether the bottoms heat up before the tops. The pipe sides do heat up before the opposite sides.

Attached are photos. All 3 are used not just to heat the rooms they are in, but also the hallway, bathroom, kitchen - that has an open wall facing a warm room with a thick riser in it, and large, open living room. So the rooms with radiators are warm, while the above-mentioned other rooms are not warm enough. I don't care if the rooms with radiators get too warm, because two of them are just for storage, while the third is my bedroom, and I turn it off before I go to bed, because otherwise the room gets too hot for sleeping. For that reason, I'm thinking of putting a TRV on it, if the radiator wouldn't be noisy. That's the red one. I may want to use a TRV on that one anyhow, since the door gets closed sometimes, while it's good to have some heat coming from there.

danb2

I checked after the heat was off for a bit, and the two radiators that were not completely hot yet did not seem to be any warmer on the bottom. The one with the D vent was already completely hot.

Fred

Check the pitch of those radiators. That is most likely the reason for water spitting out of the vents and hammer at the radiator. The first picture (the large radiator) certainly looks like it is pitched the wrong direction. They should be pitched back towards the pipe, on a one pipe system.

danb2

I found out that the small white radiator does heat up on the bottom before the top.

Re the pitch, I still haven't gotten a hold of a level, but regardless of whether that's the cause of spilling I think I'd rather have the peace of mind of having a float, as something could go wrong with the system at any time, especially since it is old and not well taken care of. Ideally, that would be with a VariValve on the end, since that has the highest output that I know of for an adjustable vent, in case I need it. So the float would need to be threaded at both ends (adapters could be used, if necessary) and would need to pass as much air as the VariValve (~0.8 CFM). If anyone knows of such a thing, I'd appreciate it if they'd let me know. Maybe one designed for a water-based system would work.

Though now that I think of it, since my vent connection is only 1/8", I wonder if the test results were for the 1/4" model and the 1/8" model might have a lower maximum flow rate, since I see the maximum orifice of the VariValve is 5/16", though I'm guessing the latter is diameter, like what's used on the Jacobus sheet, while the 1/8" is evidently radius. OTOH, maybe the higher pressure at the connection, compared to the outlet, makes the difference.

Daniel_3

Proper pitch is the master key to a properly vented system. That long rad in your first pic is a wall radiator being used as a floor radiator. Get your pitch corrected first before you try any kind of proper venting. Then follow up with an "all out" venting measure if needed. Attached is a good read for you.

Fred

Daniel said:

Proper pitch is the master key to a properly vented system. That long rad in your first pic is a wall radiator being used as a floor radiator. Get your pitch corrected first before you try any kind of proper venting. Then follow up with an "all out" venting measure if needed. Attached is a good read for you.

I think that wall radiator was taken off the wall for some reason. If you enlarge that picture, you will see where the brackets were mounted to the wall, above the radiator. I'm not sure why the OP thinks he wants a float valve on there with the vent. If he pitches that radiator back towards the inlet pipe as I suggested in an earlier post, there won't be any significant water in that radiator anyway.

danb2

Thanks for the article.

Those brackets were not used to mount the radiator. They were installed for a shelf, which I just removed, with the brackets.

I do plan to buy a new level, check the pitches and try to correct if necessary. It may be that it's just the floor not being level that makes the radiator pitch look wrong. In any case, it seems like the water is not just in the radiator(s), since the pipes make hammering noises, away from the radiators, in all three of those rooms. I do not have permission to do any work on the pipes, and getting non-critical work done on them, one way or another, is probably legally difficult, if not impossible. It seems reasonable to have a float, even when there is no water in the system, since things can go wrong in the future. Most vents have floats in them, but not the VariValve, which otherwise seems like the most flexible option, and is quite economical. So that's why I want floats on all 3 radiators.

BTW, I found out that the vent on the large radiator is a #5, while a #D and #6 are working well on the small radiators, which are closer to the boiler, though a lot of air comes out of the D at least. So it seems that a #5 will be too small for that radiator, even after the pitch is fixed (if it's wrong now, as opposed to the floor not being level). I may have fixed the failed Jacobus, by removing debris from the outlet with tweezers, and it seems that that can be used as a #D or better, by leaving off the vent port. Though long-term, I'd rather have a more reliable make. The large radiator is on the opposite long side of the apartment and may be on a different main than the two small radiators, since I know that it can be shut off from downstairs somewhere, independently from the others. Regardless of whether switching to smaller vents on the small radiators will improve performance of the large one, I'd rather go up on the latter, if I can, than down on the others, as I'd rather have increased overall heat output, if I can get it; as the article suggests.

nicholas bonham-carter

I would put some Hoffman 40's on those radiators. They are much less likely to spit.
Get a level, and check the radiators.
Make a list of the symptoms still remaining, and post it here.--NBC

Daniel_3

It is a difficult issue when living in a multiple person dwelling especially when you do not have power to work on the system. I guess a glass of beer with the super might suffice to get your point across. If you can't touch the source of the issue it's moot to expect too much from the far side of things.