Hi,

I have gurgling sounds coming from my baseboards as my heat kicks on suggesting air in the system. I have two zones, although only one is usually on at a time. I'm hoping someone can provide directions on how to bleed the system, or ad water to correct the problem. I have attached links to photos of the boiler and surrounding pipes. It is a Burnham boiler model U-14-A. The pressure and temperature seem fine (see photo) and the valve on the top of the expansion tank is loose. I would be very grateful for any advice. Thanks in advance.


Image of Boiler1 - Photobucket - Video and Image Hosting

Image of Boiler2 - Photobucket - Video and Image Hosting

Image of Boiler3 - Photobucket - Video and Image Hosting

Image of RearPipes - Photobucket - Video and Image Hosting

Image of PressureTemp - Photobucket - Video and Image Hosting

 

I would start with the loose valve. What kind of valve is it and why is it loose? There was some funny java script running on photobucket. I had to close the page.

 

Thanks, but I think that valve (its tiny) is a release valve in case the pressure builds too high. At least that is what I gathered from other posts. It is in the same position it has been in for 15 years with no trouble. Tightening it will not remove the air.

 

Then locate the return line at the boiler and look for a bleeder valve. Run the system, open the valve. If there is any air, it should release.

 

Pics are kinda small ... dark ... can't really see much ... need to pull back with the camera and get at least one or two wider shots so we can see how everything fits together...

IF YOUR GAUGE IS ACCURATE, it appears that you have around 25 PSI on the gauge at the high temp ... that's probably a bit high.

Your expansion tank appears to be somewhat on the new-ish side... was it replaced recently?

The first thing I would do is verify that the tank is in fact in good condition (i.e. bladder not ruptured) and that it has the proper air charge on it. If you've looked at other posts, you probably already know that to do this, you must turn off the boiler and let cool to 100°F or less, and then drop the pressure in the system to ZERO PSI by closing the manual water feed valve and opening any system drain and draining ONLY ENOUGH WATER TO DROP THE PRESSURE TO ZERO. Then, with a good quality tire pressure gauge, check the air charge at the valve on the bottom of the tank. If you get water out of the tire valve on the bottom the tank is bad and must be replaced. If it is dry, but less than 12 PSI, add air with a bicycle pump or a small air compressor until it is...

When that's done, open the manual feed water valve and allow the system to re-pressurize ... if your automatic regulator is working properly, the system pressure should rise to between 12-15 PSI and stop. If it continues to rise above this point, close the manual feed valve and plan on replacing the regulator valve. You can run the system with the valve closed, but in this case, keep an eye on the system pressure to make sure it doesn't drop too low, and if it does, add water by opening the manual valve. Replace the valve soon (springtime?) but, do due diligence...

The automatic water feed regulator will add water to the system as required... is supposed to maintain the pressure of the boiler between (usually, exceptions apply) 12 and 15 PSI when the system is COLD.

What kind of radiation is in the home? Fin-tube baseboards? Standing cast iron radiators? etc ?

Look them over and see if you can find manual air bleeds on them. Small valves that have either a square 'clock key' fitting or a slot for a coin or a screwdriver. You can usually buy the clock key at a hardware store if you need. If any are found, open them first with the system OFF and bleed any trapped air out. Then, do it again with the system HOT, and the circulator RUNNING ... if you had to close the manual feed valve because the regulator wasn't working, go back and check the pressure occasionally while bleeding and bump the pressure back up. If the automatic valve is working, this isn't necessary.

If you have no bleeders on the radiation, we'll get more agressive ... but do these things first.

 

Thanks NJ Trooper and Pulpo, especially for taking the time on Christmas morning.

Pulpo, I'm not sure what a bleeder valve might look like. You'll have to excuse my ignorance here - I'm not familiar with the different valves. I see several valves that look like they have handles on them and one small valve with a little screwable cap on the top just above the pressure gage - unscrewing it slightly bleeds off the pressure.

NJ Trooper - Sorry for the poor picts, but the furnace is in a small closet in a hallway and I cannot get back far enough to capture the entire set up in one shot. I've attached some larger shots from as far back as I can get. Let me know if specific areas would be more helpful.

The expansion tank has not been replaced for more than 15 years - when I moved into the house.

I have fin-tube baseboards with no bleeder valves that I can find - just straight pipe or fins.

I'm dropping the temperature now, but want to verify which valves are correct to drop the pressure. The main water feed is the yellow handle at the rear of the furnace (Pict - right side)? The drain I should use is the red spigot on the lower right side (Pict - right side)?

Thanks again!

Front
Image of Front1 - Photobucket - Video and Image Hosting

RightSide1
Image of right side1 - Photobucket - Video and Image Hosting

RightSide2
Image of RightSide2 - Photobucket - Video and Image Hosting

 

The red handled spigot in "image of right side 1" is for the domestic water. I suspect that yellow handled ball valve is also for domestic. It would appear the feed water shut off would be the left valve in your nineth picture.

You can use the blue handled spigot in "image of rightside 2" to drop the pressure.

 

Thanks Grady. I'm not sure which image you are calling the ninth - I only listed 8. Does the feed water shutoff have a color?

So the blue one is just above the circulator for the upstairs heat.

 

There are 10 photos in the album on Photobucket. The nineth is "Rear pipes". If the blue spigot is for the upstairs, I'd suggest closing the green valve below it to reduce any drainage from upstairs. There should be a spigot at the bottom of the boiler somewhere (below the circulator?) you can use to drop the pressure.

 

Thanks Grady - I think I understand which valves to turn now. I'll try all this and report back.

The only drain valve below the circulators is shown in the last Pict I just uploaded - its silver and just below the main feed line.

LowerRight
Image of LowerRight - Photobucket - Video and Image Hosting

Thanks again, Have a great day!

 

That valve will work but be prepared with a hose cap in case it doesn't close all the way. Drop the pressure just to zero. No need to drain a bunch of water.

 

Ok the pressure in the expansion tank was low (8psi) so I increased it to 12.

Then I went to turn back on the main feed, but before I did, noticed the pressure in the boiler had increased to 20 - is this normal? I did wait about a half hour after working on the expansion tank.

I want to turn the boiler back on, but wanted to get your opinion on whether this is wise given the pressure increased prior to opening the main feed.

Thanks for all the help.

 

If there is no valve between the tank & boiler, when you increase the tank pressure, you are pressurizing the entire system. After adjusting the tank pressure you need to again relieve the system pressure & double check the tank. You may have to do this a couple of times before the tank pressure is stable.

One thing you need to check is your tire gauge vs the boiler gauge. If the boiler gauge is showing 20#, so should the tank pressure. The pressure at the tire valve can show higher than the system but not lower. If the two gauges do not agree, one of them is wrong. It's up to you to find out which one.

 

I released the pressure (drained the boiler again) and checked the tank and it holds around 12. If I don't touch anything, the boiler gauge stays at 0. Then I refilled and the lower pressure gauge goes to 20. If I then take a reading at the tank, its 15. My tire gauge could be wrong, but I won't be able to get a new one until tomorrow. Any suggestions?

 

I use one made for low pressure & maxes out at 25#. A good gauge is going to be more expensive than the typical $.99 ones you often find.