Air in baseboard hot water system?
#41
Two Scoops
I see online Taco 1-1/4 air scoops for around $20. If I put a couple of those in would they go on the supply side 18 inches on either side of the upright?
The would the bladder tank hang from one of them, or would it be better on the make-up water line?
This looks like a good warm weather project, I think.
The would the bladder tank hang from one of them, or would it be better on the make-up water line?
This looks like a good warm weather project, I think.
#43
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Time to weight in and take my licks,
First getting air out of a hot water baseboard system is a PITA. I opened my system to take out a section of baseboard to put a closet door in my second floor bedroom. I got everything soldered back together (so I thought) and started to refill the system. No air bleeds on the second floor and yes, I know I should have put them in.
After trying to bleed using pump/water pressure I've finally realized I have vapor lock it it wont bleed.
First a brief description of my system. 1 pump, 2 zone control valves. pretty solid design.
Heres what I did, I forced the second floor zone on with the first floor off. when the pump was up to pressure I closed the suction side main valve, shut off the pump, opened the drain valve upstream of the shutoff vavle and pulled a vacuum on the line till I had good water flow. Worked great, right up to the point of finding the leaks, 2 out of 14 joints, Now I'm back to draining and re sweating. Sucks to be me.
Any Hints?
First getting air out of a hot water baseboard system is a PITA. I opened my system to take out a section of baseboard to put a closet door in my second floor bedroom. I got everything soldered back together (so I thought) and started to refill the system. No air bleeds on the second floor and yes, I know I should have put them in.
After trying to bleed using pump/water pressure I've finally realized I have vapor lock it it wont bleed.
First a brief description of my system. 1 pump, 2 zone control valves. pretty solid design.
Heres what I did, I forced the second floor zone on with the first floor off. when the pump was up to pressure I closed the suction side main valve, shut off the pump, opened the drain valve upstream of the shutoff vavle and pulled a vacuum on the line till I had good water flow. Worked great, right up to the point of finding the leaks, 2 out of 14 joints, Now I'm back to draining and re sweating. Sucks to be me.
Any Hints?
#45
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As long as you have to drain the system to re-solder those joints why don't you go ahead and install the vent valves? Vents should be at any high point and at the outlet of any baseboard that turns downward.
#48
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Jumping in here rather than starting another thread on the same topic. I'm new here and relatively new to this type of work but I've been able to glean some knowledge here and there while searching the internet.
Here's my system, about as basic as it gets:

I don't have bleeders at the baseboards so I've been trying to purge air at the boiler which is why the hose is there but it doesn't seem to be working. I close valve 1, open spigot 2 and after an initial trickle of water nothing comes out. The cap at 3 is loose and the water inlet at 4 is open. If I manually add water with the lever on top of the pressure reducer the boiler pressure goes up but I still get nothing out of the hose. I'm stumped...and cold, please help.
Here's my system, about as basic as it gets:

I don't have bleeders at the baseboards so I've been trying to purge air at the boiler which is why the hose is there but it doesn't seem to be working. I close valve 1, open spigot 2 and after an initial trickle of water nothing comes out. The cap at 3 is loose and the water inlet at 4 is open. If I manually add water with the lever on top of the pressure reducer the boiler pressure goes up but I still get nothing out of the hose. I'm stumped...and cold, please help.
#49
Weird!...
That green thing to the left of the air scoop and expansion tank is a 'flow check' valve. There's a 'disc' inside that gets pushed up to allow flow when the pump is running, but falls down again when the pump stops to prevent 'ghost flow' in the system.
Perhaps that disc is 'stuck' ... the knob on top should manually lift that disc by turning counter clockwise. Try that. It will probably free up the disc if that's the problem. Remember to return it to clockwise when yer done.
Check ALL the piping for any other valves that may have been inadvertently closed.
Another thing you can try just as a 'sanity check' ... with the boiler COOLED below 100°F, open valve 4 and lift the lever on the regulator valve. You should get flow through the boiler and out the hose. That will prove that the valve is supplying enough water. It may be that the valve is plugged partially and only allowing a trickle of water ... although since you say the pressure builds in the boiler, may not be the problem... but easy enough to check. You should get a decent flow ...
Perhaps the reason you are having an issue with air in the system is due to some other underlying reason ... maybe related to the feedwater regulator also ... what are the operating pressures on the boiler when it's HOT and when it's COLD ?
By the way, this is an excellent time to check/adjust the air charge on the expansion tank. If you can't find the instruction to do so in one of the other recent posts here, let me know ...
I'll retype it if I have to ... but there are several recently.
That green thing to the left of the air scoop and expansion tank is a 'flow check' valve. There's a 'disc' inside that gets pushed up to allow flow when the pump is running, but falls down again when the pump stops to prevent 'ghost flow' in the system.
Perhaps that disc is 'stuck' ... the knob on top should manually lift that disc by turning counter clockwise. Try that. It will probably free up the disc if that's the problem. Remember to return it to clockwise when yer done.
Check ALL the piping for any other valves that may have been inadvertently closed.
Another thing you can try just as a 'sanity check' ... with the boiler COOLED below 100°F, open valve 4 and lift the lever on the regulator valve. You should get flow through the boiler and out the hose. That will prove that the valve is supplying enough water. It may be that the valve is plugged partially and only allowing a trickle of water ... although since you say the pressure builds in the boiler, may not be the problem... but easy enough to check. You should get a decent flow ...
Perhaps the reason you are having an issue with air in the system is due to some other underlying reason ... maybe related to the feedwater regulator also ... what are the operating pressures on the boiler when it's HOT and when it's COLD ?
By the way, this is an excellent time to check/adjust the air charge on the expansion tank. If you can't find the instruction to do so in one of the other recent posts here, let me know ...
I'll retype it if I have to ... but there are several recently.
#50
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Weird!...
That green thing to the left of the air scoop and expansion tank is a 'flow check' valve. There's a 'disc' inside that gets pushed up to allow flow when the pump is running, but falls down again when the pump stops to prevent 'ghost flow' in the system.
Perhaps that disc is 'stuck' ... the knob on top should manually lift that disc by turning counter clockwise. Try that. It will probably free up the disc if that's the problem. Remember to return it to clockwise when yer done.
That green thing to the left of the air scoop and expansion tank is a 'flow check' valve. There's a 'disc' inside that gets pushed up to allow flow when the pump is running, but falls down again when the pump stops to prevent 'ghost flow' in the system.
Perhaps that disc is 'stuck' ... the knob on top should manually lift that disc by turning counter clockwise. Try that. It will probably free up the disc if that's the problem. Remember to return it to clockwise when yer done.

Another thing you can try just as a 'sanity check' ... with the boiler COOLED below 100°F, open valve 4 and lift the lever on the regulator valve. You should get flow through the boiler and out the hose. That will prove that the valve is supplying enough water. It may be that the valve is plugged partially and only allowing a trickle of water ... although since you say the pressure builds in the boiler, may not be the problem... but easy enough to check. You should get a decent flow ...

Got it, on that now.
#51
but now the check valve is leaking after I reclosed it.
No flow at all.
How 'adventurous' do you want to get?
#52
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Just below the knob, there is a gland nut, and below that is the big-a55 nut that holds the whole thing together. Under the gland nut is a 'packing' that seals the stem. I'm guessing that's where it's leaking now? If so, tighten that gland nut just a wee bit, only enough to stop the leak. That will squeeze the packing a bit tighter and seal the stem.
It sure does sound as though the regulator is plugged up ...
How 'adventurous' do you want to get?
It sure does sound as though the regulator is plugged up ...
How 'adventurous' do you want to get?
#53
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Well, I feel like a dummy. I hadn't been running the baseboards much since we installed a wood stove this year and well, one of the pipes, right above the garage door was frozen. $100 and a hole in the ceiling later, I know what the problem was and where to find it next time. Beer 4U2
#56
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Sloshing Sound
Great reading through this thread. I recently replaced the TACO circulator on my system as I was not getting any circulation through my baseboard heating. Seems to be working fine, however when my thermostat calls for heat and the system goes into action, I hear a loud sloshing noise for about 10 seconds. This goes away for the most part, but I occasionally hear the sound of water sloshing through the pipes. All gages check out normal, with levels as you have suggested. Also checked pressure in overflow tank and that reads 14psi.
Is this sloshing sound normal, or is there air in the system? If so, how do I bleed?
Thanks.
Is this sloshing sound normal, or is there air in the system? If so, how do I bleed?
Thanks.
#58
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Pictures
Thanks for the reply. Here are some photos:
tjh22 - Photobucket - Video and Image Hosting
As the photos indicate, this is a two-zone system, but Zone 1 is shut down due to renovation.
Any instructions you can pass along so I can get the air out of my system would be most appreciated.
Thanks again.
tjh22 - Photobucket - Video and Image Hosting
As the photos indicate, this is a two-zone system, but Zone 1 is shut down due to renovation.
Any instructions you can pass along so I can get the air out of my system would be most appreciated.
Thanks again.
Last edited by tjh22; 01-06-09 at 08:19 AM. Reason: Revised URL
#59
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Pix
Thanks for the pictures. Big help.
In picture 3 it appears there are purge valves (red handled hose bibs above the yellow handled ball valves). It would also appear the zone being renovated to be shut down via the ball valve.
To purge, connect a hose to the other red valve, close the yellow, manually lock open the zone valve, put the other end of the hose into a bucket, & open the red valve. Allow water to flow until you no longer get air bubbles.
In picture 3 it appears there are purge valves (red handled hose bibs above the yellow handled ball valves). It would also appear the zone being renovated to be shut down via the ball valve.
To purge, connect a hose to the other red valve, close the yellow, manually lock open the zone valve, put the other end of the hose into a bucket, & open the red valve. Allow water to flow until you no longer get air bubbles.