Noisy baseboard HW heat.....help!

John Henry

It had occurred to me that adding the 3rd zone (maybe 7 years ago) may have caused it, or been when it started.

Here are links to some pics, I'll see if I can attach them is well. Not sure if this forum allows pics.

Any ideas from the pics?

http://home.attbi.com/~johnshenry/miscpics/furnace_1.jpg
http://home.attbi.com/~johnshenry/miscpics/furnace_2.jpg
http://home.attbi.com/~johnshenry/miscpics/furnace_3.jpg


JH

John Henry

Noisy baseboard HW heat... help!

Hello Forum.

I have a problem with my heating system that has been driving me nuts for years. I am an avid do-it-your-selfer and in fact added the 3rd zone for my basement when I finished it years ago.

Problem is a loud bubbling water sound in the upstairs zone, mostly at night it seems. Wakes me up often. Air in the lines no doubt. I can flush the zone and the problem will go away then be back in 1-3 weeks.

I have replaced my air bleeder valve at least once, it is installed over the bladder tank at the furnace outlet (I think it is the outlet).

My system pressure stays at about 11-15 PSI. If I boost it up using the lever on the back fill valve (20 PSI or so), the problem will go away until the system settles back down to around 11 PSI and a week or so, then it is back.

A year or so ago I replaced a leaking gasket on the tankless HW coil in the boiler. Had thought that that might be where air was leaking in, but it didn't have an affect.

Ideas? My tehory is that air is getting in somewhere, and/or the bleeder valve isn't working for some reason. I have been considering adding a bleeder valve on the upstairs zone (3 floors, basement, forst and second floor) but that seems like a band-aid. I suspect that air in the system is normally generated in any system, and air "leaking in" to a pressurized system doesn't make much sense anyway.

Comments? Suggestions?

Thanks in advance...


John H.

jg2700

is there a air scoop on the header of the boiler.and does the boiler have a built in scoop if it does there should be a vent installed in that tapping.most times guys feed it there or plug it.

kevin

where is...

the circulator located in the system? depending on the piping, when the circulator would come on it could actually pull air into the system.Is there 18" of straight pipe before the air scoop? Is there a leak somewhere in your system? Seems strange that the pressure continually drops. Any buried piping? Piping in a crawlspace? I am hinking more along the loss of water more than the addition of air being the problem...kpc

Ben_3

Air problem

John, This sounds like one of those nasty air problems that never goes away. Only what if it's not an air problem. In your post you mentioned that you added a 3rd zone to your system and that this has been an ongoing problem for years, What if the upper zone now is the more restrictive path for the water to flow. Is the pump the same size as it was when it was only two zones? Maybe the pump can't handle the increased load when all the zones are calling, causing the upper zones flow to slow enough that the pressure drops and that air pops out for a wake up call. Hey if those zones are manifolded together in the boiler room it might just as well be an air scoop. Or maybe those auto vents just don't work. Maybe John it is time to call a qualified contractor to look at your system. If they know their boilers and piping they should be able to diagnose the problem first hand. All it would cost is a service call and you could always still do the job yourself, or sit back and let them fix the problem, you may find it's not as much $$$ as you think, and you might just sleep better at night.

[Deleted User]

Got pictures??

Just guessing here, but in my experience the majority of "air problems" comes from the fact that the pump is in the wrong position in relation to the expansion tank. In your case, I'm guessing it is probably on the return going back into the boiler. Go to Books and More (to your left) and buy Dans book "Pumping Away". Read it apply it and sleep silently at night.

ME

Dana

From the pictures you posted, I see the Watts 9D backflow valve is on the boiler side of the Watts autofeed valve. Because the backflow valve is atmospheric and is at low pressure being on the boiler side of the auto feed, when the pump sarts it may create enough of a pressure drop at the backflow that it pops open and introduces a very small slug of air into the system. That air would end up somewhere, probably the highest zone. I would also not have a problem running the system at 15- 18 psi, helping to keep water up in the top zone. Try relocating the backflow to the house side of the auto feed, or simply purchase a new Watts 911 Combination backflow/auto feed and install according to instuctions, I think the problem will go away.

Dana

OOPS, just took another look at the picture with my glasses on, I was wrong. Don't see any reason your getting air in the system from the pics. you posted.

John Henry

Adjustable autofeed valves?

Do they make auto feed valves with adjustable pressures? If I manually open the valve and even get up to maybe 16-17ps- at the boiler gauge, the problem goes away. And I actually was just about to replace the auto feed valve *the lever rusted off). Should I get a different kind than I have there now? Any places on line to order such a thing?

Thanks for all the helpful advice...

JH

Dana

The one you have is adjustable. Having said that, if the valve is old you may want to replace it and then set it. If you adjust the one you have, it may fail and overpressurize the system. If you want to try, remove the cap with the lever on it by unscrewing it, loosen the lock nut and turn the piston with a srewdriver in 1 turn at a time until you get the pressure you want, reset the locknut and re-install the cap with the lever. Keep checking the pressure for a day or so to make sure the valve doesn't overpressurize the system. This, of couse, assumes the gage on the boiler is reading accurately.

John Henry

Ah-ha. I have the new one right here next to me, there is no way I am doing anything with that old valve other than replacing it. I can see what you mean, and see the tag that says "Set 12-15 PSI" and "Range 10-25 PSI". Does this mean that I can only set it to 15 PSI max?

BTW, I have in the past, and will again after I change the valve, run it up to 30+ PSI and insure that my safetly valve opens up.. as well as monitor it for a few days ahead. Thanks for the help!!


JH

Mark Walnicki

Pump away

from the expansion tank. The only sure fix is to take the circulator off the return, and mount it on the supply downstream of the expansion tank. While the system is empty I would replace the auto air vent on the air scoop, replace the expansion tank, and upsize the common return to the boiler from the zones to whatever the boiler tapping size is.

After that, playing with pressures should be a thing of the past, and you will typically see a steady 15-18 psi under all load conditions with no air noise.

Jeff_8

noise in pipes

Just noticed you have a flo-check valve in a system with zone valves. Maybe the noise isn't air. Have you checked to see if the zone valves are installed in the correct water flow direction.

AL_6

I always place my circulators on the feed downstream from expansion tank on new instalations, but on existing such as yours i would not go threw the labor. I have found numerous times your exact problem can be solved by installing a spirovent. Air scoops do not and i repeat do not remove the same amount of air from a system as a SPIROVENT no matter where it is placed 18 inches or not a useless cheap peice of old time chunk. And stay away from some of the SPIROVENT rip offs. There are other manufactures that make good air seperators but not many. With the way you are purging it is almost imposible to remove all the air, plus water contains gases, and you will always draw air into the system so you need to remove it as the system operates all the time. And yes remove the flow valve. Your problem is common and minor, i have dozens of customers who lived for years like that till i came and placed a SPIROVENT in, and now they love me. And you dont need 18 inches from the elbow. Any advice is tough without seeing the job but try it you have nothing to loose.