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

Hot Water Gas Boiler Question

STvex Member Posts: 41

I purchased my home this year and have a few questions about my Weil Gas Hot Water Boiler. Prior to this, I used to have a steam gas boiler. I attached two pictures of the boiler. These are my questions:

1) Is there a water level gauge or can I install one? I would like to know the water level in the boiler. My prior steam boiler used to have tube where I was able to tell how much water was in it.

2) Is there a low water cutoff for the boiler? If the boiler doesn't have enough water, is there a way to install a low water cutoff to shut down the boiler?

3) How do I tell the how much pressure is in the boiler. The current gauge seems to be at 0, I am assuming it should be reading 15 psi.

4) What general maintenance is required for a gas hot water boiler? Does the water need to be drained and refilled periodically? Any chemicals to add to the water?

5) How to I remove the rust on the boiler panels and what paint can I use to repaint the panels?

I appreciate the help. Thank You.


  • Jamie Hall
    Jamie Hall Member Posts: 16,323
    Hot water boilers do not need a sight tube for water level -- it would be useless, as the entire system is -- or should be! -- always full of water. For a similar reason a low water cutoff would not normally be installed.

    The only way to tell if the system is correctly charged is by the pressure -- and you are correct, it should be around 15 psi. This pressure is held reasonably steady hot or cold, by either an expansion tank or a compression tank. I can't tell which you have -- I would need a much more comprehensive picture of the system near the boiler for that. With the gauge reading 0, there are really only two possibilities. First, the gauge is shot. Second, there isn't enough water in the system to compress the expansion tank or compression tank properly. You can also go to one of the upper floor radiators and open the bleeder on it; water should come out. If not -- problems. Try that and find out and report back, if you would.

    On the drain and refill and chemicals. It really shouldn't usually be needed.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • STvex
    STvex Member Posts: 41
    Thanks for getting back to me. I forgot to mention, i have slant fin baseboard heating. No bleed valve. Does it make any sense to add an additional air separator on one of the second floor piping? I added three more pictures, where can I get a good pressure reader, I think the one I have doesn't work. Does the rest of the piping look decent?

    EBEBRATT-Ed Member Posts: 9,394
    If you could, stand back farther when taking pictures. You can drain the boiler and install a temp/press gauge or in a pinch if you have a drain valve on the boiler with a valve install a gauge on the drain valve temporally.

    You can buy a pressure gauge with a garden hose fitting attached to it or buy a gauge and a few fittings and make up your own.

    Pressure should be 12-15 psi when cold. When heated the pressure will rise maybe to as much as 22-24 this is normal

    yes low water cutoffs can be added if you have a taping for one. They are required on new installs in most areas, in years past they were not required
  • Jersey2
    Jersey2 Member Posts: 40
    I think that is the same boiler that I will end up with. CGa series 3. After you confirm the pressure with a garden hose fitting pressure gauge, I guess get another pressure gauge like is on it, and swap it out. I think it just screws into a fitting. To me the piping looks fine and it is only 4 years old. Do you have indirect heat for your domestic water, or an independent water heater? Also I would want electronic ignition and no pilot light.
  • STvex
    STvex Member Posts: 41
    Can you post a link for the low water cutoff, electronic ignition, and pressure reader for this model. I have a separate hot water heater tank right next to it. Thanks.