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Help with Relay Switch (Our Heat won't go on!)

*nods* Your turning the wrong knob to fill the boiler. If you show us some pictures of your boiler and piping we may better be able to describe and point out which valve you need to open to add water to your system.

When taking the pictures, try to get "the big picture" and take a few from different orientations.

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  • Todd G
    Todd G Member Posts: 12
    Need Help! Have a Tyco SR 501 Relay and water tube won't fill

    Hi - We have a oil fired steam radiator heating system and the boiler has a Tyco SR 501 Relay One Zone switch (I think it is a low water safety cutoff device - it's attached to a tube which is usually half full of water - when it gets low, we were told to turn the knob to add water). I was draining the dirty water off the system earlier, and the water in the cutoff tube started bouncing up and down and, suddenly, the tube was empty. The power light on the SR 501 Relay is now off. When I turn the knob to add water to the safety device, no water comes in and the light on the relay is still off. ANY help is super-appreciated, as we may be stuck now with no hot water! Thanks so much! -- Todd
  • Big Ed_3
    Big Ed_3 Member Posts: 170
    Dirty gauge cocks

    The two valves or taps ,top and bottom of the gauge glass seem to be plugged and needs to be cleaned to show a actual water level .. From here my guess your still low on water.
  • Todd G
    Todd G Member Posts: 12
    We can't get water to go in the glass gauge tube

    Hi - Thanks for the reply - when we turn the knobs (for lack of a better word), no water goes in - we can turn the knob below that releases the dirty water in a bucket til it goes clear, and that water comes, but when we turn either above or below the glass tube, no water moves - is there a way to get the water to start going into the glass again?
  • Todd G
    Todd G Member Posts: 12
    one more update

    and now when I turn the valve to release the dirty watter, there is no water left to come out (we turned off the emergency switch for the boiler) - any advice? thanks (our first steam system)
  • kevin coppinger_4
    kevin coppinger_4 Member Posts: 2,124
    i don't think...

    you are turning the right knob...
    unless you can sow us some pict. you need to make a phone call to a plg. / htg. contractor who knows steam.....kpc

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  • I think there's a bit of confusion

    Do you mean a Taco SR501 ? And the green power light isn't on ? Look at the front of the boiler and tell us the brand and model number of the other components . You should see a pressuretrol and a low water cutoff . The Taco is a relay , not a low water cutoff .

    When you turn the knob to add water can you actually hear water filling the boiler ? You don't mean the knob connected to the sight glass , do you ? Make sure both of those knobs are open - twist them counter-clockwise . When water is in the sight glass can you see the level dropping ? How often do you have to add water ?
  • Todd G
    Todd G Member Posts: 12
    Pictures for help

    Hi - Thanks - Here are some pictures! You guys are amazing and we appreciate your help - (ALSO - now, when I turn the lower valve to empty the dirty water into the bucket, no water goes in - so I basically can't get any water to go into the glass tube or probably even the boiler, and the light on the Taco SR501 is off) - Todd

    (P.S. - I took about 30 pictures to get these that I cut it down to and also saved them as smaller pictures size so as not to overfill here - thanks again)
  • Todd G
    Todd G Member Posts: 12
    Pictures posted in previous message

    Hi all - not sure if I have to post a separate topic, but I put 7 pictures of our heating system in a reply to Norm's message - thanks
  • Which valve

    are you turning to add water to the boiler ? Is the water feed pipe in the back of the boiler ? I didn't see it in the pics .
  • Todd G
    Todd G Member Posts: 12
    Couple more pics - can't figure out which valve/pipe brings h20

    Hi - here are a few more pics - I can't find out which pipe it is or valve to control it that brings water into the boiler - only one valve is in off position and that is the new looking one pictured at the top of the first and last pic here - when I turn it to on, sounds like water starts to flow (but not sure where to/from). Thanks for any advice
  • kevin coppinger_4
    kevin coppinger_4 Member Posts: 2,124
    now we are getting

    somewhere....the copper pipe that runs by the smokepipe and probabaly into the bottom of the boiler...has a ball/lever valve in the off position. Turn that to the on/open position to fill the boiler....The water line should be 1/2 way in the glass....
    You REALLY need someone to come by and go over your system w/ you....I would also get Dan's book "we got steam heat" to get you up to speed.....

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  • Todd G
    Todd G Member Posts: 12
    Getting somewhere, I think

    Hi Kevin - OK, we got water into the boiler by turning that valve to the open position, and got the water level in the glass tube to half way, then turned off the valve. Now, will the system start to work or is there something else we should be doing - I'm assuming I had to turn the valve back off or else the water would just keep going (or was it normally open and got flipped to off by the system). Thanks
  • Todd G
    Todd G Member Posts: 12
    2 Questions

    One more thing - in addition to my previous question on whether that valve should be left in the on position or off position (I never touched it, so I'm assuming it should stay in "off" - I just turned it on to add water to the boiler, then when the glass tube got half full, turned it back off).

    2nd question is should the knobs at tob and bottom of the glass tube be left open (counter clockwise) or tightly closed and then only turned when the water level is low? Thanks - Todd
  • Ron Schroeder
    Ron Schroeder Member Posts: 998

    Leave thae valve you turned on to add water off unless your adding water.

    The two red handled valves at top and bottom of gauge glass leave then on to be able to se what is happening in the water column

    Next should be a call to a professsional
  • Scott04
    Scott04 Member Posts: 69

    The system should work once you turn it back on.

    I second the opinions that you need to get a pro in there to explain the system to you as well as label the valves. From what you have told us, it sounds like someone explained it to you (perhaps not as clearly as they could) and you only remembered parts of it. The labeling of the valves will help you're memory in the future!

  • Todd G
    Todd G Member Posts: 12

    Hi all - Thanks so so much for all the help - after doing what you said on Sunday, the system did go on once water was added and worked fine since - I did take the advice to call a professional who walked us through the system (concurring that everything you all recommended was right). Thanks again !
  • That Watts low-water cutoff

    the black cast-iron ball to the left of the sight glass, is a real museum piece. If you're going to keep that boiler for a while, I'd have your pro change the Watts to the McDonnell & Miller #67. An electric valve can hook up to the #67 to automatically feed water when needed. I prefer the newer valves with brass bodies rather than the older cast-iron #101A which has a tendency to fill with rust.

    It also looks like you have two dry returns hooking together above the boiler's waterline, with a small air vent mounted above. If you have a two-pipe system this piping arrangement is OK, but the vent probably should be bigger. If it's one-pipe the two returns should drop below the boiler's waterline before joining, and each should have its own vent.

    You've come to the right place to learn about steam heating.

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  • Steve L.
    Steve L. Member Posts: 35

    The knobs and the top and bottom of the "glass tube" should be fully open.

    The ball valve you opened to add water to the boiler should be off unless you need to add water.


    It is possible to add a automatic water feeder to your boiler. This device will keep water in your boiler on it's own.
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