Boiler System Gurgling Noise

ken22079

Hello, I’m still a novice with my radiant system.  I had the system reworked over the summer bc the original was a hack and some zones was not flushable unless an original zone is open.

its looks good but I’m getting some gurgling noise in the circulator pump.  I’m wondering the the design wasn’t good.  I noticed the boiler outgoing did not have shut off valve.  That’s the first fix.

The second fix is swapping out the Taco 007-F5 circulator pump with the 007e.  I read this auto purge any trapped air in the circulator.  Also quiet.  My question is the gpm on the F5 is 23gpm and the 007e is 16gpm.  Will this work?  Or should I have the boiler outgoing line tweaked some how?

Thank you in advance.

Intplm.

If you are hearing some gurgling in the system, that is commonly trapped air that may need to be manually purged out. The" auto purge"? that you mentioned and I'm guessing, is probably the micro air bubble separator just below the expansion tank.
If the noise is not too annoying you might not need to manually purge the system of the suspected air as it may, over time purge out from the air separator.
If not, then it will need a manual purge.
Are there any installed? I don't see any in the picture.

Intplm.

Another thought.
The way the fill is piped. You might be drawing air in from the microbubble air separator due to the close proximity of the Circulator.
I really can't tell for sure from here.

HVACNUT

The end switches are being used? Meaning the circulator only starts once a zone valve is open?

hot_rod

What static pressure are you running? Adding 5 or so psi can help get problem air out

You might remove the top of the air purger to be sure the float is not stuck snd check the condition of the rings

ken22079

Here is a better image of the entire system.  I do see a drain but needs another shut off valve. It’s so hard find a contractor that has the knowledge to instal it correctly.  We had to swap out to the right size expansion tank. The taco was at the max limit.

pedmec

it looks like you have a purge valve on the left side of the boiler. looks like a webstone ball valve and purge. you can purge the air out from there. just shut off the ball valves to all the returns except the zone you want to purge and shut off the webstone and open up the purge and that should do the trick. looks like the installer was trying to save a little coin on the installation

ken22079

Thank you for all the input.  Prior to swapping the expansion tank it was always reaching 25psi but its holding steady at 15psi.  I can bump it up to 18 to see if it’ll help.

Boiler is in the basement, heats main level and top level if that info helps.  I think I found the math  to determine the psi and thought it was ok.

The pump only turns on when the thermostat calls for heat and opens the valve.

I think I will have 2 additional shut off valves installed on both in/out line of the boiler installed.  Then an additional drain valve on the outgoing manifold.  This should make all purging tasks much easier.

The auto purge feature on the 007e model engages when it detects air in the circulator.  It automatically drops the psi down then send a burst of high psi through to push the air out back into the system so the air separator can remove it.

hot_rod

The auto purge just speeds up the pump to max rpm to try and push air around

the return pipe on the left side if the boiler, is there a shut off valve with a hose valve above it? That would allow you to power purge one zone at a time

usually if you hear the air in the mechanical room the air purger should eliminate it, it has made its way out of the zone

ken22079

Update - I increased the boiler to 18psi and it did not make a difference.  I got a contractor in to assess the boiler layout.  Agrees that both supply and return need shut off valves.  

He suggested I have separate drains for each zone.  Suggested adding an automatic air vent at the boiler supply to mitigate additional trapped air. He didn’t like the placement of the circulator pump but didn’t really offer a suggestion. 

My questions
1. Are  the individual zone drains necessary if I can simply shut off all the zones to purge the zone in question? Already have a drain.

2. Increasing the supply line to allow more straight pipe to the taco air separator would help?  Currently is about 14-15” of straight pipe.  

3.  Suggestion for relocating the circ pump? Requiring switching the orientation making it parallel with the floor. Would this make difference?  I hear it needs 7-8” straight pipe before a 90 turn to help reduce ‘noise’
4 .  Adding drain to supply manifold so I can easily purge air from circulator pump.
5. Automatic air vent

I marked up the image to help illustrate the change.

hot_rod

As I see it all you need is a ball valve somewhere, anywhere on the return line to the boiler. Then a purge valve at the end of the return header. You have return shutoffs to purge one loop at a time.

Turn off power, manually open all zone valves, shut off all but one return valve, purge till clear. Turn off that ball valve, move to the next and repeat.

Restore power and let all zones run to confirm a clean purge

Pump is fine, you have adequate air separation, you just need a few critical valves to manually purge