We are close to completion on a remodel at Lake Tahoe, CA. However, our new hydronic system makes snap, crackle pop noises that are loud and last for some 20 minutes. We appear to have staple up construction without plates. Is this the problem? How could be best solve the problem and get to a no noise hydronic system? Suggestions welcome. Thanks, Rob Reis

Rob,
I've got my PEX just hanging in the joist cavity waiting for me to make up my mind on the attachment method.  I was all ready to order a staple gun and 300 staples and be done with it.  I've heard of the noise issues but didn't figure they'd be that bad... I've also read about metal straps that the Pex is zip tied to, or stand off  clips that allow the tubes to slide.  If you could do it again, what would you use?

Ben

Rob,

I posted a response in the other thread, but in case you don't see it...

Per your question about my hydronic installer, it was Jack Rabbit Plumbing in Minden. They were great. No complaints at all. They installed my system with plates. The advantage to the plates is that they draw the heat out of the tubes. They're cheap and easy to work with if you want to add them.

As for the noise, I also have noise problems. However, maybe it's a coincidence, but it appears that once I've insulated the noisy area, the noise stops. I hear it - snap, crackle, pop - whenever the boiler fires up. It never lasts more than a minute or two, but it's annoying. 20 minutes would drive me nuts! So I sympathize.

I still have two noisy spots, but I'm hoping they go away once the insulation is in place. So far I've used RMAX and shoved the sheets right up against the hydronic tubes. My other noisy spots went silent as soon as they were insulated. Is your floor insulated? Do you have anything directing the heat upward (ie: RMAX)?

-Rob

Ben, I am not sure what to do. However, I have made several calls to people to see if they can figure out the cause of the noise. The guess right now is that the panels were only stapled along the middle and not at the edges. This is causing them to 'sing' when they warm up. I have attached a photo of the existing installation. I welcome comments from anyone on what is the cause of the rice crispies noise. Rob

Without insulation, you're in worst case scenario. That is, maximum heat up, maximum cool down equals maximum expansion/contraction issues. Insulation is a must.

Those plates appear to be floppy but it's hard to see based on the picture. they need to be firmly attached to the subfloor or they don't do you any good.

You should have some sort of variable temperature control on teh system as well, using outdoor reset temperatures or better.

It can be tricky getting noiseless systems with lightweight plates in the joists though, using regular PEX. Possible, sure, but tricky sometimes.

Noise is caused by the expansion of the Pex.  All Pex products expand as they are heated.  1" per 100' for every 10 degree rise over ambient temperature.  This is made worse if the system does not have distribution plates.  the distribution plates allow for the system to run at lower water temperatures.  control logic has a lot to do with it also.  slow operating zone valves and constant circulation is the key, also, weather controled mixing valves.  Cheapen the system you get what you paid for.