A lot of noise coming from manifold on 2nd floor (circulator in the basement)

Sergea29

Hello I had a new radiant floor heating system installed over the summer. I had issues with the install and had to have the contractor back to fix certain things a couple of times. I am still doubtful about the install and am not getting much help from them with regards to some questions I have. An important one is that is it normal that the system has been running all winter and the system bled often that there can still be a lot of noise at the manifold. My heating is on the first and second floors with the boiler and 1st floor manifold in the basement. I have a secondary circuit going to a manifold on the second floor (this is the one with the noise) with a circulator on the return in the basement. I have a Bosh Greenstar boiler and there is also a circulator on the return for the 1st floor manifold.

Thanks,

Serge

hot_rod

noise like air or gurgling sounds? Send a pic of the piping in the boiler room. There needs to be a good air separator installed properly, near the boiler.

That may be a primary/ secondary piping and air removal can be a bit harder to accomplish..

Are there air vents on the manifolds?

Sergea29

Thanks. I will send later tonight. You cand find a sketch of my setup in an earlier November post:

Looking for comments on my radiant floor boiler hook-up

Serge

Sergea29

So yes you described the sound perfectly.

Here are 2 pictures at the boiler and one at the manifold

Thanks,

Serge

Zman

It is hard to tell how the boiler is piped from the picture. A sketch or more pictures would help.
The pumps on the returns are a red flag as is the pump selection of 26-99. As an experiment, you might try closing the air vents on the manifolds, turning the pumps to low and making sure the system pressure is at least 15 psi.
There are multiple issues with the installation which are causing your problems.

Sergea29

Thanks for the comments. What do you mean by pump selection 26-99? Also, the air vents at the manifolds are already closed

Here is a sketch of the installation and some more pictures

steamedchicago

Sergea29 said:

Thanks for the comments. What do you mean by pump selection 26-99? Also, the air vents at the manifolds are already closed



Here is a sketch of the installation and some more pictures

26-99 is a model of Grundfos pump. I assume he can tell that's what's installed. (I can't, but I'm not a professional.) It's a pretty big pump, and quite likely oversized for the application. Too much pump wastes electricity, and increases flow rates. Too high flow rates can cause noise, pipe erosion, and other problems.

hot_rod

The air vents on those manifolds have hygroscopic caps, they don't shutoff when screwed down.

It shipped with two black plastic caps, used for pressure testing. If you still have those take off the brass caps, install the black caps and tighten down.

Also try tightening the cap on the riser by the boiler.

I don't see any central air removal device, just the float vents?

It looks like those high head circs are pumping towards the expansion tank. If so those air vents that are not capped tightly can actually allow air into the system.

Zman

If the pumps were installed facing out, there would be a model number on the motor. The casting looks like a 26-99 which is way too big.
It is hard to follow the piping to see if it is per instructions. You may need to draw it out.
Regardless, if the original installer does not want to come back, that would be a good thing. The workmanship is horrible.
Getting pro in to get this straightened might be the best plan.

Sergea29

Thanks everyone.

Zman, when you say draw it out, the picture of the sketch is not clear? It is the actual representation of the install. What would be a reasonably sized pump for 1000sqf ( basement to 1st floor) and same for 900sqf (basement to 2nd floor).

Hot rod, what you see is all that is there. No air removal device.


Serge

DZoro

No air elimination device, really bad install overall. piping, pumps, workmanship. It's actually amazing that it is actually heating. Re pipe while installing air device.

Zman

Sorry, I did not see the drawing, that is very clear.

You have pumps in series all pumping into the expansion tank. The pressure at the expansion tank is constant. Because the circulators are pumping towards the tank, the energy they are converting is subtracted from the system pressure. By the time you get to the manifolds, the pressure is likely negative which is why you are having a problem.

The system should be repiped primary secondary with circulators pumping away and with proper air elimination as described in the installation manual. I would also recommend verifying the circulator sizes. Over sized circulators cost more to buy and operate and will not last as long as properly sized ones.

hot_rod

Yeah, I don't know how you could go about correcting some of the issues without starting over, sadly.

I would us a hydraulic separator at the boiler, size the circulators correctly, and just clean it up.

It should/could look as simple as this piping example.

https://www.caleffi.com/sites/default/files/file/idronics_19_na.pdf

Sergea29

I would like to thank everyone for their help. If anyone wants to comment, i checked the circs and the one for the 2nd floor radiant is a 26-99 same as for the hydronic air handler but the one for the 1st floor is a 15-58.

Serge

Zman

Those circulators are oversized. You may mitigate some of the symptoms by installing more appropriates ones.
You really need to have the whole thing repiped per manufactures instructions. Keep in mind that if you ever have a warranty issue with the boiler, it may be declined if it is installed incorrectly. All they had to do is read the installation manual...

Sergea29

Thanks again Zman!

I would have another question: what would be a typical flow rate for a typical installation like mine. You are probably missing some important info to comment on this but I figured I'd try.

Serge

Zman

You can ballpark your 1/2" loops at .75 GPM each.
On the fancoil if you take the BTU rating and move the decimal 4 digits left (50,000 BTU= 5 GPM) that will get you close.
There are plenty of people on here who can run the numbers for you if you post the details.

cutter

Zman or Hot rod Is the expansion tank even installed correctly? Reading the directions on a tank of that type the tank should be rotated 180*. Or does it really matter?

hot_rod

plenty of conflicting info out there on expansion tank mounting, even from the manufacturers

I have seen plenty of side mounts out there lasting as long as nipple up mounts

As far as I can tell base mount tanks with nipple on the bottom are the same as your mount?