QUESTION FROM Nance Lee

My son knocked a radiator screw off while lifting weights in the basement. We lost a good deal of water (maybe three or four gallons). Now, one radiator in the kitchen is ice cold. The rest are warm and seem fine. Will the system replenish itself or do I need to do something (add water - how? or call a repairman) - thanks!

ANSWER FROM HOME-WIZARD

Dear Nance Lee:

A couple of thoughts regarding the problem you are having after you lost so much water from your radiator system:

1) Regarding your question about whether the system will replenish itself, your system should have an automatic make-up valve installed in it, which brings in fresh water as your system has loses, expansions and contractions, etc. So assuming that this valve is there, and is operating properly, you should be alright and the system should replenish itself with water.

2) However,regarding the problem you are having with no heat in your kitchen, since you have heat in you other zones, it sounds like the problem is just related to your kitchen zone. Chances are that when you lost so much water, that the kitchen zone may have filled up with air. So if you haven't already, you might want to try to bleed your kitchen radiators. If you are not sure how to do this, you can look in our online Maintenance Library, on the Baseboard Heating System page:

http://www.home-wizard.com/maintenance/baseboardheating.asp

Hope this is helpful.
Home-Wizard.com

FOLLOW-UP FROM Nance Lee

Thank you (sorry I accidentally posted three times - I hit refresh to see your answer!)

While all the other radiators have a similar bleed screw, the kitchen one does not (of course). It is smaller than the others and built under the counter - I can only access one side of it and there is no screw there. There is a large valve that comes out of the floor - should I unscrew that? There is also what appears to be a bolt, maybe half inch diameter, on the side in the middle (not at the top where the other screws are). It has been painted over and appears to have never been opened.

FOLLOW-UP FROM Nance Lee

Me again! We figured out how to take the screw out of the cold radiator in the kitchen. There is a big 2 inch diameter hole now, and nothing is coming out - air or water. How long do we wait? Also the pressure gauge on the boiler reads sreo (not a good thing, but also confusing since every other radiator is working fine). Maybe that gauge never worked; I honestly don't remember looking at it once in the past 17 years I have lived here (not a good thing either!) Thanks in advance -

ANSWER FROM HOME-WIZARD

Dear Nance Lee:

I was just about to suggest that you try to carefully un-screw the bolt that was half-way up (being careful because there could be hot water squirting out). This could be a way to test if there is air or water in your kitchen radiator.

But if you are saying what you opened is about 2 inches in diameter, and there is nothing coming out, then I'm wondering a couple of things: 1) if maybe this plug is not an opening in the water jacket of the radiator, but rather a mounting bracket of some sort; or 2) if it is indeed an opening to your radiator water jacket, then if the water supply to your kitchen radiator has somehow gotten shut off.

To answer you question about how long you would have to wait, the answer is not very long. If this was an opening to your radiator (and the zone valve to this radiator was open), and your water make-up valve was operating properly, you would see air or water coming out almost immediately.

When you had the original leak when your son knocked off the radiator screw in the basement, is it possible that the zone valve for the supply to your kitchen radiator got shut off when trying to contain the leak? One way to check is when you look at the zone valves in the basement, do all of them appear to be in the same position?

The other thing that is troubling is that you were able to find bleeder valves for all of your other zones, but not for the kitchen. You said that the kitchen radiator is built under a counter, and is it possible that the bleeder is tucked in a hard to reach spot? Do you have a small mirror that you can use to see the back side of the top of this radiator?

Regarding the boiler valve reading zero but the other zones are working, it could be a bad guage as you suggested, it could also be that there is a valve in the piping before that guage that is shut, and therefore the guage is not able to read the boiler's pressure.

If the above doesn't let you solve the problem, just let us know what you find out, and we'll try some other ways to diagnose the problem.

Regards,
Home-Wizard.com

FOLLOW-UP FROM Nance Lee

OK. The expansion tank on the second floor is completely empty. The radiator in the kitchen must have created a vacuum. When I try to bleed a different radiator it sucks air IN instead of letting air out. So I am about to open the valve to fill the boiler. I am thinking I should just do it to maybe 10 feet instead of the complete 20 feet it normally is at, to go slow and not let it pressurize too much so fast that the tank overflows. Then I will probably have to bleed all the radiators too, right? Please let me know if I am on the right track. Thanks!

FOLLOW-UP FROM Nance Lee

Not sure if you saw my newest question, right before M Hart's last post. Thanks!

ANSWER FROM HOME-WIZARD

Dear Nance Lee:

You system should NOT be drawing air IN. From your description, I'm wondering if it was your water make-up valve that was damaged. If your automatic water make-up valve is not operating correctly, this could explain why your system is not pressurizing properly, and why your kitchen zone has gotten air locked, and why you are not able to bleed it.

Can you tell if your make-up valve is working?

Regards,
Home-Wizard.com

ANSWER FROM HOME-WIZARD

Dear Nance Lee:

It sounds like the problem maybe how you are re-filling and bleeding your system. Especially since it sounds like your expansion tank is still empty (when it should be about half full after you have bled your system, or until water starts to flow out of the overflow connection).

Here is a link to a webpage that describes various hot water systems:

http://www.usace.army.mil/publications/armytm/tm5-642/chap5.pdf

Section 5-3 of this webpage describes the startup procedure for filling and bleeding your system. Hopefully by following this procedure, your entire system (including the kitchen radiator and your expansion tank) will be able to fill, and solve your problem. If not, please let me know what you find, and we'll keep working on figuring this out for you.

Regards,
Home-Wizard.com

FOLLOW-UP FROM Nance Lee

Well, it took me about 5 hours yesterday but everything is working perfectly now! I had to start with the third floor radiators (there are 5 of them) and work down. Each time I bled off air I had to go back to the basement and repressurize to 20 feet again. I bet I did 100 flights of stairs yesterday! But eventually the kitchen radiator refilled with warm water and all of them are working beautifully. Thank you so much for your patience and that great diagram! My husband was impressed that I actually read military specs to fix the boiler system!

ANSWER FROM HOME-WIZARD

Dear Nance Lee:

Thanks for the feedback. We're glad to hear that this helped you to solve your problem. From your description, it sounded like it had to be related to how you were re-filling your system. And it seemed like the diagram would help for your particular system.

Regards,
Home-Wizard.com