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Radiator vents, damaged by water?


I apologize in advance if this sort of question has been asked before, but I couldn't find anything definitive when doing a search.

On our one-pipe steam system the automatic water feeder failed in the open position. The result was a flooded boiler and water traversing up the pipes and out some of the vents in the radiators. The feeder issue has been resolved. (i.e. we got a rid of it and I'll be doing manual feeding from now on. Don't need to come home after a long weekend away to that again.)

My concern is that the radiators vents may have been damaged from the water going through them. After the fact, heat seems to be working fine, but just curious if water going through vents damages them in someway or if water through a vent is no big deal.

Thanks to all the contributors here. I've learned so much from you all.


  • neilcneilc Member Posts: 809
    if you are rid of the water feeder,
    what do you have for a low water cutoff?
    do you service it regularly ?
    we are talking life safety here.

    how often are you adding water manually?
    can the boiler go "a long weekend" without needing refilling?
    (it should and then some)

    as for the question of the vents,
    likely they all drained back down when you lowered the flood level,
    if everything is heating as it should you are probably good.
    are you having issues?

    do you know your system pressure?
  • AbracadabraAbracadabra Member Posts: 1,948
    edited January 2017
    What kind of a water feeder?

    Water should not damage steam vents.
  • FredFred Member Posts: 8,423
    They shouldn't be damaged. It is possible, if you find some that don't close when steam hits them that some crud could have washed up into them and they may need to be taken off of the radiator and washed out but they should still be good.
  • ChrisBeachChrisBeach Member Posts: 3
    Thank you for your responses. Glad to know the vents will most likely be okay. So far no issues.

    Hopefully, I won't have to manually feed the boiler too often. It's only been a couple of days and the water has held steady in the sight glass. I wouldn't expect a need to fill it on a regular basis. If so, then I'm losing water somewhere and that's a whole other problem.

    The low water cutoff is a McDonnell & Miller 767.

    System pressure is a little less than 2 lbs.

    Water feeder was a McDonnell & Miller.

    Thanks again!
  • neilcneilc Member Posts: 809
    and you know to blow down the 767 weekly to keep the internal float operating freely ?
    pg 12
    (this may be what hung up the feeder)
  • AbracadabraAbracadabra Member Posts: 1,948
    Even with weekly maintainance, you can get sufficient crap buildup in there that will require disassembly and cleanup. But yeah, imho, the correct way to have approached this would have been to repair the problem why the feeder overfed the boiler. Not eliminating the feeder.
  • FredFred Member Posts: 8,423
    If the feeder is a McDonnell Miller 101a, the replacement parts cost almost as much as a new unit costs. The 101a builds up so much gunk in them, like tar, the solenoid, the strainer basket, the gaskets and then the valve seat is still questionable (at least in the one I had). I took mine off too when it failed. It doesn't have a meter on it and I wanted to manage the added water myself. They are a nice accessory if you travel a lot and they are maintained annually but eventually they do fail. Checking on the boiler, at least weekly and knowing how much water is being added is a good thing as long as you are 100% sure you test that 767 LWCO weekly when you blow it down to make sure it works properly. They need annual service too. Taken apart and scraped out, float checked to make sure it doesn't have a pin hole in it and isn't water logged, clean the blow down valve (if it's the spring loaded one, the full port ball valve, not so much)
  • ChrisBeachChrisBeach Member Posts: 3
    Thanks again for all your input. Always helpful.

    Yes, generally I do weekly blowdowns during the heating months. The 767 (ball valve type) was replaced a couple of years ago, but I didn't know they require annual maintenance. (thank you for that instruction manual!) I will make sure to start doing that. Without the feeder in place I can now test the LWCO when draining the water.

    I think the feeder is a nice convenience, but I don't travel much beyond a weekend here and there to visit family so I'm comfortable keeping tabs on the boiler level. We purchased the house five years ago so I'm not sure how old that feeder was. It may have just failed due to an age. And as Fred pointed out, now I'll know directly if I'm losing water for any reason.

    Cheers guys
  • BobCBobC Member Posts: 5,112
    I agree completely. As long as you know the LWCO works and your not going to be out of the house for weeks, manual feed is the way to go.

    When I was working I'd be away for 2 or 3 weeks at a time. I did have someone come in to feed the cat on a daily basis and check on the boiler. In 8 years they never had to add water to the boiler.

    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
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