Water surge sound when ""zone Valve opens""

Rick143

Hey guys, When my hot water boiler circulating pump kicks on I hear a quick big water surge sound, then quiet after that.. I don't hear the water going through the pipes like air being trapped at all just a Quick surge sound " like a office water tank " would make when you get a cup of water. What is causing this ?

EDIT : Its more from when the ZONE Valve opens and not from the pump that I get this big surge sound.

Thanks for any help !

Zman

It is likely air in the pipes. What is your system pressure? Is this a home?

Rick143

Yes this is my home, 1400 sq ft ranch. Pressure is around 17 psi.

NY_Rob

Sometimes you need more flow to dislodge air pockets than the auto-fill valve will supply in it's normal operator mode during a purge. See if your auto-fill valve has a "fast/quick fill" feature. If it does, look up it's usage instructions and purge with the "fast/quick fill" enabled.

Rick143

Yes I have purged using that method with the same results.

hot_rod

do you have an air purger near the boiler. It should evacuate that remaining air after you purge

Rick143

hot rod said:

do you have an air purger near the boiler. It should evacuate that remaining air after you purge

Yes I do but as I had stated in my other thread about that subject with the " Service valve" that was installed, and I firmly believe its not letting any air out of that vent because of it ! Even when the boiler was filled I never heard any air come out that vent.

NY_Rob

If you have a modern boiler, close all zones but the problem zone and run the CH pump in purge/test mode (at full speed if it's a variable speed pump) for 30-60min.

Rick143

NY_Rob said:

If you have a modern boiler, close all zones but the problem zone and run the CH pump in purge/test mode (at full speed if it's a variable speed pump) for 30-60min.

Seems to happen on all 3 zones, All 3 return lines go into one 1 1/4 line that has only one purge valve. I am not aware of a purge/ test mode on the pump, Just has 3 different speed settings Hi, Med, Low. So doing as you suggest would I be still isolating the boiler by turning off the valve ? or am I purging as is ?

NY_Rob

^ Without seeing your system... the idea is to isolate the zones so only one zone is active at a time and the others are closed off- then run the CH pump at max speed to get the highest possible flow through that one loop till it's quiet. Flow will still go through the boiler, but only through one zone at a time increasing velocity and hopefully pushing out the trapped air.

The CH pump "purge/test mode" would be found in the installer menu of the boiler. If you don't have that... you have to find a way to power your CH pump without firing the boiler. When I used to have a conventional cast iron boiler with an aquastat- I would record the settings, then set it very low so the CH pump could come on even with cold water in the system then set it back to standard settings once the purge was complete.

Rick143

Here is a pic of my system, I don't have a way to isolate each return of all 3 zones as they converge to a 3 way into a 1 1/4 pipe, Then to the boiler at that point is a purge valve. I have 3 zone valves going out and I can isolate the feed of each from there but not return.
Heres what Im thinking is my issue, if I cant isolate each return when I purge one zone at a time, it will draw water from the other return zones during this prosses and defeating the purpose by creating air in those zones because it will draw water out during the purge. I don't know what to do here, Am I right about this ?

Rick143

This is the sends, Zone valves portion.

NY_Rob

^ open one zone valve, close the other two zone valves then purge. Once silent, close the open zone valve, open the next one and purge till silent, then close the second zone valve and open the third zone valve and purge till silent. You'll always have one open zone valve and two closed zone valves.

Rick143

NY_Rob said:

^ open one zone valve, close the other two zone valves then purge. Once silent, close the open zone valve, open the next one and purge till silent, then close the second zone valve and open the third zone valve and purge till silent. You'll always have one open zone valve and two closed zone valves.

Yes I understand that part and have done this and still have this issue, I was just concerned about how all the "returns" coming together to one 1 1/4 pipe, then to the boiler where the purge valve is as seen in the photo. Seems like on the return, it would draw form the other return lines because they are all together with no isolation at that point. I appreciate your help !!

Rick143

This is where the returns converge together and what Im talking about, Notice they have some kind of butterfly valve on each but they do not move and are locked up.2 have the levers broken off also. That point must have been where you could isolate the other returns as you where purging one Im thinking. EDIT: If that is the case, Could I just open all 3 zones and purge all at one time ?

NY_Rob

As long as you close a zone valve(s) that zone(s) is isolated as far as purging is concerned.

hot_rod

Fill water goes in at the expansion tank location, thru whatever zone valve you lock open, around thru the heat emitters, back down to the boiler.

Turn off the red handle ball valve, purge from the boiler drain (yellow handle) above the ball valve.

Do one zone at a time, crank up the fill valve to maybe 25 psi to flush , as that brand only fills at around 3 gpm.

Other brands of fill valves flow 5 gpm at any set pressure to quickly fill and flush, it takes at least 3 gpm in 3/4 copper to get a good purge, the more the better.

Unfortunately it looks like the circulator is pumping towards the boiler and expansion tank? If so the air purger may not be doing much air removal to get remaining air out when the water heats up.

Pumping away from the expansion tank really helps get and keep air out, especially on chronic air problem jobs. The purge from the hose assures some flow, the air purger should clean out the rest, when installed properly.

How high above the boiler to the top most heat emitter? Sometimes adding some fill pressure helps squeeze problematic air out.

JUGHNE

It looks like ball valves on the supply and return of the boiler which should isolate one from the other and prevent the relief valve from opening with the house pressure.

Rick143

hot rod said:

Unfortunately it looks like the circulator is pumping towards the boiler and expansion tank? If so the air purger may not be doing much air removal to get remaining air out when the water heats up.

Pumping away from the expansion tank really helps get and keep air out, especially on chronic air problem jobs. The purge from the hose assures some flow, the air purger should clean out the rest, when installed properly.

How high above the boiler to the top most heat emitter? Sometimes adding some fill pressure helps squeeze problematic air out.

Yes the pump is on the return facing down back into the boiler, The expansion tank is on the feed line, If you look close its on the other 1 1/4 line on the rear of the boiler.. It seems like I can hear air trapped in the pump at times and once in awhile through certain zones. I have tried increasing the water pressure during purge with the same results. This is so puzzling to me because when it runs for awhile it gets quiet and I don't hear any air in the system at all, Then it cools down and starts doing it again.. I have also bleed each Room manually with the coin vents with very small amounts of air If any at all... Its very frustrating, The only consistent thing that happens is the loud surge each time the pump kicks on.

Rick143

All though the auto vent on top of the air out is new is it possible its not working ? Just a thought...

Rick143

Here is a better view of the system.

hot_rod

Do you ever hear air coming out of the vent on top of the purger?

If air is passing thru, and not gathering and expelling from that vent, it may not be working. Float could be stuck, or the needle valve plugged up. Remove the cap and press down the stem inside an see if air, or water comes out of the vent.

Ideally a micro bubble type air separator and the circulator moved to downstream of the expansion tank, would bring the system Uponor to proper best practices. Remember air hampers heat transfer in the boiler and radiators, need to get all air, big and small evacuated.

When water is heated, air is driven out of solution, needs to be eliminated then. As the water cools when you first start the air is back in solution and flowing with the water. That could explain noise only on cold start. also air will collect at high points when the circulator is off, and push around to the boiler and pump on first start.

And, air can be pulled into a vent like that if the piping and circulator allows for low or negative pressure to be developed at any air locations. After a purge, and the boiler runs to limit, try tightening the cap on the air vent and see if it stays air free.

Rick143

I don't hear any air coming out of that vent above the Air Out, That's why I think it could be bad even though its brand new. I just went down and removed the plastic cap and poked a nail into it and nothing came out... hmmmm I think it might not be working, I am going to change it out and see what happens..

hot_rod

Put a service valve below it so it can be serviced inn the future.

Sometimes you can just loosen it and see if air comes out at the thread, if so it could be a plugged vent.

Those iron body air purgers do not do a good job of getting micro bubbles up to the vent. Upgrade and change some components location if you have a chance. Air, even micro bubbles disappear within an hour or so with a good air sep.

Rick143

I changed out the Auto Vent, I see why I couldn't get anything to come out with the nail inserted in there because there wasn't anything to push on, It doesn't seem like anything is bad with it but we will see. When I turned the water back on with the other Auto Vent in place, some air and water did spray out for a quick second so that one does work.


This is the pic of the one I removed

Rick143

I purged all 3 zones again and for awhile the "water surge" when a zone valve opened up was very minimal, I still heard some air in the system.. But now its back like before. I even lowered the pump speed from Hi to Med. I just don't get it......

hot_rod

> @Rick143 said:
> I purged all 3 zones again and for awhile the "water surge" when a zone valve opened up was very minimal, I still heard some air in the system.. But now its back like before. I even lowered the pump speed from Hi to Med. I just don't get it......

Your air purger isn’t and can’t do an adequate job, that simple

Grab a copy of Pumping Away from this site and learn the mechanism behind efficienct air removal

MikeL_2

What type of zone valves do you have; manufacturer & model?

MikeL_2

I had a similar issue with Taco Zone Sentry valves......

Rick143

MikeL said:

I had a similar issue with Taco Zone Sentry valves......

I have those I believe, Its this one in the picture >>




What problems did you have and how did you resolve it ??

MikeL_2

There was an intermittent surging or velocity / flow noise as the Zone Sentry valves opened ; it could be heard throughout the first floor of the home. I spent several days on site to witness and isolate the sound. A rep firm sent someone from Taco - they could not explain why this was happening, but did give me 570 series replacement valves which I installed........have not used the Taco Zone Sentry valves since........I'm hoping the administrator will move this thread to the main wall; would love to hear from someone from Taco regarding this issue .....

Rick143

Wow that's the same problem I have !! Did the other zone valves resolve your problem ?

I have edited my post as this is more the problem and not caused by the circulating pump. I can stand there watching the zone valve open and instant loud surge is heard. I will try to get a video of it.

hot_rod

What about speed 1 on the circulator? Sounds like high velocity (over pumped) flowing thru the valve if it makes noise when opening or closing.

Zone valved systems work best with delta P circulators, but it should be noise free with a fixed speed circulator.

MikeL_2

In my case we used a Taco Viridian circulator. The Viridian has three operating modes and multiple settings for self adjusting & fixed speed control - the surging sound was evident intermittently at every speed.........The noise stopped when we replaced the Zone Sentry valves!

Rick143

hot rod said:

What about speed 1 on the circulator? Sounds like high velocity (over pumped) flowing thru the valve if it makes noise when opening or closing.

Zone valved systems work best with delta P circulators, but it should be noise free with a fixed speed circulator.

I tried it on all speeds and it does the same thing, The sound is a very quick surge as if there is a void that gets filled quickly.

Rick143

MikeL said:

In my case we used a Taco Viridian circulator. The Viridian has three operating modes and multiple settings for self adjusting & fixed speed control - the surging sound was evident intermittently at every speed.........The noise stopped when we replaced the Zone Sentry valves!

What did you replace them with ?

MikeL_2

Taco 570 gold series zone valves.....

Rick143

Rick143 said:

MikeL said:

In my case we used a Taco Viridian circulator. The Viridian has three operating modes and multiple settings for self adjusting & fixed speed control - the surging sound was evident intermittently at every speed.........The noise stopped when we replaced the Zone Sentry valves!

What did you replace them with ?

That's the ones that were on my boiler to begin with !! LOL

woodrow

is the noise only when 2 zones are running and one shuts or does it do it on a call for heat with just one zone how are they wired the circ is not powered on all the time only when end switch closes

woodrow

you can remove the head and open it manualy before the pump turns on and see if it still makes the noise maybe the pump is coming on before the valve is fully opened if this is the case wire a time delay on the end switch to tt

Rick143

The surge happens no matter what zone vale(s) is open or not open, Its all the time. I have no idea about a time delay or how to implement it. I have a HydroStat 3200 plus and the Taco Sentry zone valves, Thanks.