Ideas on Quieting Vibration from Pumps

cloves

Hi all, I have 2 pumps powering my radiant heating system (yes they are large tacos) and I was wondering if anyone had any thoughts on how to quiet the vibration they cause on the wall they are located on. I have the system and piping being held on the wall by copper bells. I was thinking some rubber pads and shimming the system hold points with those pads.

But wanted to see if any of the pro's had some better ideas or photos etc.

Jamie Hall

First thing I'd do is make sure the pumps are operating correctly. That type of pump -- even very big ones -- may hum, but they shouldn't have a real vibration to them. Proper inlet piping (adequate straight pipe into the inlet?), proper system pressure (pumping away, or if not enough pressure to ensure you are not having cavitation). Seals good. Etc.

Then yes, you can put rubber pads in on the pump mounts, if they have separate mounting hardware, making sure there is no hard connection. Also a length of flexible pipe on both the inlet and the outlet of the pump before you get to anything solidly tied down (vibration will transmit a long way through rigid pipe).

GroundUp

Which model pumps are they? Both making the same sound? I would be concerned about air in the system or lack of straight pipe on the suction and discharge of the pump. The double digit Taco units are pretty notorious for flying apart in either of the aforementioned cases. Quieting the vibration won't fix the root of the problem; even the big fellas shouldn't be any more than a hum

EBEBRATT-Ed

Take them off the wall and mount them on the floor. The floor has more mass to absorb vibration. Connect the piping with flex connectors if need be

hot_rod

yeah, any of the wet rotor circs should run virtually silent? The higher RPM high head style tend to hum a bit.

If it's zoned, switch to ECMs that will modulate, save energy, and tend to run completely silent.

cloves

Hi everyone, thanks for the input so far never got a notification of a reply. I comped up a quick drawing to share and took a photo since piping was mentioned. The guy who designed my radiant heating is a joke, poor details when I had question come up. I added a spirovent and the backflow preventer after reading more on radiant heat. I also insulated my pipes and heat exchanger to optimize my water temperature.

Some more details as well:

• Two circulators SS Taco #008 & #0011
  
• Piped using 3/4" except for intake make up side which is 1/2" (Could this be the issue? Should the system be 1inch pipe instead?)
  
• 12 Zone manifold (Only 4 currently connected)
  
• Closed loop system
  

Perhaps a heavy hum/vibration makes more sense. I took a youtube video of the system running. I can feel the vibration through the studs and can hear feel in the room its directly above. I used a few copper bells for the pipes and some L brackets below the pumps. Figured it would take some weight of the pipes.

The system occasionally blows my #30 pressure valve. Every once week or two, I open my hose bib and let some of the water out the bring the pressure down. But it seems to creep back up slowly. According the my gauge its sitting around 20psi and it should operate at 12psi. I have opened up the differential bypass valve some more. I am thinking the issue here could be the first expansion tank I have not being big enough. Both expansion tanks are set to my city water pressure.

Down the line I would like to get one of the newer electrically controlled circulators (non taco which is beyond expensive). The system currently used about 300 watts running. That includes the controller and 2 pumps (not the water heater).

The larger sized drawing is also attached so its more readable.

Youtube Video (Sorry for the breathing, I was crawling over a bunch of boxes on the floor)(The noise isn't as loud on the video)

https://youtube.com/watch?v=p2pnNBZYL8M

SuperTech

Why are you using a ST5 potable water expansion tank on the boiler? Those are for domestic hot water, not hydronic heat.

neilc

the manifold loop expansion tank should only be pressurized to the mani loop pressure, 12#.
you must isolate that tank and drain it prior to setting it's air pressure to 12.
It also seems your feeder might be leaking by, try isolating it, shut off the manual valve, and then keep your eye on the manifold system pressure for a day or two, then a week or two, then ??
that should stop the discharging safety valve.

is there a 3rd line from the bypass, a line that is not drawn?
where does it bypass to?
post a real picture showing all this.

JUGHNE

If I am seeing this right, your exp tank on the heating side of the HXG is set for 60 psi. You want to run your heating well under 30 psi.

The HXG isolates the domestic system from the heating system.
That heating tank should be set for 12-15 Psi to match the pressure of the PRV. At 60 you don't have much of an expansion area available. Your tank is pumped up pretty tight and little of the heating water would push into it as it expands.

Don't know if that will quiet down the iron pump or not, but may keep your 30 psi relief valve from opening.

Is the PRV piping connected to the inlet circuit of the HXG as shown? It is usually connected to the cold water ahead of the boiler. Once the system if filled and all air out you should be able to shut off the water supply. If pressure drops then you have leaks.

What does the bypass valve pass??

All very interesting.

Jamie Hall

Why is the heating side set to 60 psi? The pressure tank on the heating loop should be set, when empty, to the desired system operating pressure -- 12 psi -- which should also be the setting of the pressure reducing valve.

If you should be so fortunate as to have the correct valves, this isn't hard to fix -- with the system shut down, isolate the pressure tank, drain it of water, and set the air pressure in the tank to 12 psi (or possibly a smidge less -- there's an argument which says the tank should be pressurized to slightly less than the operating pressure) and then bring it back on line.

That should cure the pressure relief valve problem.

If the pressure continues to creep up over time, the pressure reducing valve may be leaking by slightly. Try closing its valves (you do have isolating valves?) and see what happens. If it continues to creep up, you might have a problem in the heat exchanger...

cloves

SuperTech said:

Why are you using a ST5 potable water expansion tank on the boiler? Those are for domestic hot water, not hydronic heat.

I am using a Vertex water heater to provide the heat to my system which also supplies my domestic water needs. That is why the part that connects to that side is stainless steel and not iron (closed system)

neilc said:

the manifold loop expansion tank should only be pressurized to the mani loop pressure, 12#.

is there a 3rd line from the bypass line that is not drawn?
where does it bypass to?

Damn dumb over sight on my part. I just checked the expansion tank on the radiant side and it is set to #12psi! I just saw the sticker I put on it when I first installed it. I put air in the tanks when they were disconnected so they should be correct.

I also made an error in the drawing by the bypass valve. Now everything on here is correct including more photos. The drawing is also attached since its hard to see in small size.

hot_rod

got the bypass adjusted correctly

0011 on 3/4 pipe?

cloves

hot rod said:

got the bypass adjusted correctly



0011 on 3/4 pipe?

That is what I am starting to suspect could be an issue. Radiant heating guy said it was fine but now I am not so sure. That pump is massively oversized especially since I only have 4 zones running. All my lines are less then 300 ft (most are are 250).

I adjusted the differential bypass using Taco's procedure. Closed the valve, turned on all the zones for a few minutes, then slowly opened and put my hand on the top valve (the one going horizontal in the drawing) till I felt heat then stopped.

I just shot another video with a run through of the system just in case the photos aren't clear enough.

https://www.youtube.com/watch?v=gF08S2puTnQ

JUGHNE

Someone here in the past suggested that using the DHW tanks for heating purposes could be a problem.
The DHW tanks have a stiffer bladder than the hydronic ones.
Even with only 12 PSI inside, the bladder may not flex enough for low pressure expansion. FWIW

cloves

JUGHNE said:

Someone here in the past suggested that using the DHW tanks for heating purposes could be a problem.
The DHW tanks have a stiffer bladder than the hydronic ones.
Even with only 12 PSI inside, the bladder may not flex enough for low pressure expansion. FWIW

That's an interesting point!

SuperJ

Sometime in the future I would install the proper pumps. I realize you probably don't want to spend the money on that right now.
Get some sort of Delta T pump for the primary side (DHW), that way it will slow down when the heating load is reduced, and a Delta P for the secondary side.
In the meantime I would probably open the bypass with all the zones open, until the flow is where you want to be. That will reduce the DP and might quite things a bit. (keeping an eye on the temp delta 10-20f but will take a long time to stabilize with the mass of a slab).


Something like this for the secondary (not really that expensive):
https://www.homedepot.com/p/Grundfos-ALPHA2-15-55F-Cast-Iron-Circulator-Pump-with-Ternimal-Box-99163903/302859603?MERCH=REC-_-PIPHorizontal1_rr-_-302859621-_-302859603-_-N

neilc

that makeup water line may be (is) piped too far from the tank, on the negative curve of the circ, and is getting get drawn from as the circ starts.
ideally it would piped in between the tank and the loop, or between the tank and circ,
set the pressure and shut the ball valve and keep an eye on it.

cloves

SuperJ said:

Sometime in the future I would install the proper pumps. I realize you probably don't want to spend the money on that right now.
Get some sort of Delta T pump for the primary side (DHW), that way it will slow down when the heating load is reduced, and a Delta P for the secondary side.
In the meantime I would probably open the bypass with all the zones open, until the flow is where you want to be. That will reduce the DP and might quite things a bit. (keeping an eye on the temp delta 10-20f but will take a long time to stabilize with the mass of a slab).

So technically my radiant guy oversized both pumps ? I have seen a few of the new ecm pumps that are variable speed. Seems like they are much cheaper then the last time I checked. How would one of these pumps fit into an older system? As far as I understand my thermostat calls for heat, that calls goes to the taco controllers which then open the actuators and power both pumps.

If I have to get new pumps, it has to get done. The price of having a one size fits all clown design my system.

neilc said:

that makeup water line may be (is) piped too far from the tank, on the negative curve of the circ, and is getting get drawn from as the circ starts.
ideally it would piped in between the tank and the loop, or between the tank and circ,
set the pressure and shut the ball valve and keep an eye on it.

I will bleed some of the water and get it to where it has to be and then shut off the make up water. Since the system is sealed I assume it should be safe and not need daily monitoring right? The water shouldn't disappear.

neilc

well you want to know it's not leaking, so check it a day or two, then a week or two, worst that happens if pressure drops is you loose heat, or start hearing noises(water running),
and,
if the pressure keeps rising, then as someone else said, you have to suspect the heat exchanger could be leaking from the higher domestic side to lower pressure heating side, (or the makeup ball valve leaks too),
having fun yet?
so, check it a day or two, then a week or two,
you'll want to know it's not discharging, right?

SuperJ

Definitely fix everything mentioned here first. But you don’t have to get new pumps. It’s seems very likely your are oversized but you don’t really know until you look at you system curve and the pump curve and match you flow/pressure requirements. But if you do they will be more efficient and I don’t think you’ll hear a wet rotor ecm pump unless something is really wrong with the installation.

I lot of jobs seem to get whatever pump is on hand regardless of it’s suitability. Usually oversized. You can always balance your circuits and set your bypass up to technically work with the existing pumps.

SuperJ

Also, I would pull the pump head off the the impeller housing and check the impellers for debris.