Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

Watts low water cut off

john123
john123 Member Posts: 83

I have an old Watts low water cut off currently installed which is leaking. It seems very expensive to repair. Should I just go to a new model or are there real advantages to keeping this device—"Watts 50"— which seems like an old fashioned but reliable? device.

Comments

  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 16,746

    Get rid of it. It's a safety device and it needs to be reliable. You can use a Hydrolevel electronic LWCO with the proper Hydrolevel fittings

    STEAM DOCTOR
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 9,667
    edited May 2024

    Not sure that @EBEBRATT-Ed has the best advise here. He may be spot on, but that will depend on what you are using the boiler for and if your boiler has a tapping for an electronic LWCO.

    • Is this a residential single family heating system?
    • Is this a water boiler or a steam boiler?
    • Does this have only LWCO contacts? or does this have Alarm or water feed contacts that are being utilized?
    • What brand and model number boiler do you have?

    That Watts 50 is designed to be rebuilt and should have been installed with periodic maintenance in mind. Is it installed with a blow down valve below the float chamber?

    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?

  • john123
    john123 Member Posts: 83

    @EdTheHeaterMan thanks for your interest

    I am thinking of using it with an atmospheric Weil McLain CGA? water boiler although I am open to other suggestions. The house is large and has 2 rental units.

    Why is important to have LWCO, alarm or water feed contacts; I thought that the idea was to just run the power (AC) first to the LWCO and then to the pump and boiler. When the "chamber" runs dry and the float drops— this breaks the connection which cuts off the AC power to the pump and boiler.

    I can guess but what is a blow down valve and what does it do. There does not appear to be any valve below the float chamber.

    The rebuild kit is more expensive than a modern LWCO; I wonder if there is a way to replace the gasket if that is what is leaking,. Once again are there any great advantages in this older piece of kit? It does look very simple and reliable.

  • Steamhead
    Steamhead Member Posts: 17,475

    @john123 , post some pics of the boiler and the LWCO. Let's take a look at it. The CGa is a hot-water boiler, and if you're using a LWCO designed and rated for steam, it's probably not a good idea.

    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Consulting
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 9,667

    Can you post a photo?

    As far as placing a LWCO like the #50 on a water boiler, you probably do not need to flush the float chamber, as you would need on a steam boiler. (although I would provide one if the job specified the #50 LWCO). So just placing a electronic LWCO like the https://www.supplyhouse.com/Hydrolevel-45-1100-Safgard-1100-Low-Water-Cutoff-w-Auto-Reset-Burner-Circuit-Test-Button-24Vwill work just fine.  It can be installed in a tee fitting on any pipe above the boiler. As far as alarm contacts or automatic water feed valves are concerned, those are not necessary on a water boiler because you handle those functions differently on a water boiler. As far as wiring a mechanical LWCO in the 120 VAC or 24 VAC circuit to open a set of contacts when the water level drops below a safe operating level, that job is too easy. Just break the circuit with the dry contacts of the #50 control.

    When you add an electronic probe type LWCO to a system, You need to provide uninterrupted power to the control so that the electronics are powered up in order to close the contacts on the low water cut off in order to operate the burner. If you do not have power to the electronic LWCO, you will never get a call for heat to happen because the dry contacts that interrupt always fail in the safe position. "OPEN Contacts” or Burner off position. And there are many plumbers that can not follow electrical diagrams that have more than 3 wires in the circuit. Just like electricians are often shocked when they need to deal with gas pipes or water pipes.  That was a joke… Get it? Shocked?

    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?

  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 16,746

    @john123 Your first post said you had one installed and it was leaking.

    Then you said you said "thinking of using it on a Weil McLain CGA" ????

    Watts LWCO were never very popular at least where I am. Some of their models are only rated for 15psi steam so probably not the best choice for water