Replacing an Infloor mixing station

Alan (California Radiant) Forbes

I have to replace one of these and I imagine there will be plenty more in my future seeing as they were very popular here back in the 90's and 00's. I could go with a simple circulator and mixing valve, but I am also interested in another "mixing station". I see Caleffi has one (do they sell them without a manifold, hr?). Has anyone had experience and satisfaction with others?

Thanks in advance!

hot_rod

Looks like PB tube also?

Caleffi does have mixing blocks, thermostatic or motorized mix valves with delta P cir option.

You may want to replace the manifold also? I doubt you will find a mixing block that matches tooth manifold spacing.

I think Sioux Chief still sells PEX X PB couplings. Maybe , extend all those lines up a couple feet and remount a new pex manifold/ mixing station.

JUGHNE

I have 3 of these Infloor stations in my house, installed in 1995.
They were quite practical in that you get a temp control valve with digital readout, 4 way mix valve, (no dead head concern for main pump), adjustable flow control manifold blocks and boiler relay. Very compact set up IMO.

The push in connections were starting to fail, I was trying to add more circuits and the "O" rings would not hold pressure of the blocks I had in storage.

One pump run a remote manifold, that got a new manifold, the mixer/temp control still works and is in use.

Another unit had water leaks that ruined the digital read out/boiler relay control. The relay could be replaced, but I can switch it manually as needed. My ModCon will only max out at 125 so it safely works for infloor heating. That unit got a new manifold also.

The third unit works fine other that the manifold/pump is below the level of floor tubing. It will get "ghost flow" thru the tubing and possibly over heat the floor. I have flow control valves sitting on the shelf to correct this problem. (they are getting dusty BTY)

This is the shoemakers house that needs attention.

What really matters for you and your customer is: I have 1/2" OD PBOX tubing, (O2 barrier). My new manifolds are 1/2" PEX.
The transition coupling is Watts Quick-Connect P-602;
CPVC, PB, PEX,,,,1/2" CTS X 3/8" CTS ,,,,,Seatech is the manf.

Jacobsens of Adair IA was the jobber/supplier for me. About 5 bucks per connection with collet locks, in 2013 .

I also got the collet clip for locking the collet in place to prevent pull out, as these things never get looked at again.

Ironman

Viega has this if you don't wanna replace the manifolds. ODR, variable speed mixing. They work great.

JUGHNE

The Infloor manifold was also a potential problem in that the adjustment knobs could not be easily rotated after years of flow.
If I had to change this out for a paying customer I would highly recommend changing everything but the tubing.
The stop valves that come with the pump module eventually leak or fail to operate also. FWIW.

Paul Pollets

I've replaced many of these over the years. The manifolds tended to fail at the o-rings and leak. All had Pb tubing attached. The fix was a new brass or SS manifold(s) and a FPHX and SS pump at boiler. Transition fittings were used to connect the Pb to the new manifolds. In one case, the 7 manifolds in the home failed and flooded the home with black boiler water and ruined the Brazilian cherry floors causing over $100K in damages. The home was owned by the local congresswoman. Funny, I had bid the project 18 years ago when it was being built for a Sonics player. I was deemed"too expensive" by the GC.

JUGHNE

I was very lucky that I ended up with red PBOX tubing. It's O2 barrier must be effective as my system had CI GV boiler, black piping, copper (used 30 years elsewhere before I demoed it out of a bank) to the manifolds and a steel shell DHW HXG.
Changed the boiler out a few years ago, water was looking good, little black in the bottom of boiler. All piping still in use since 1995.

Alan (California Radiant) Forbes

Thanks, everyone for your ideas and resources!

I ended up replacing it with a Caleffi mixing valve and a Grundfos 15-58 pump. I really didn't want to replace the manifold, but it started leaking at the dials as soon as we pressurized it.

Jughne and hr: I'll see if I can find those parts. Again, thanks.

Paul: The Laars boiler and cast iron pump seems to have weathered the non-barrier tubing, so I'm taking the cheap route without a FPHX.

hot_rod

Here are the Sioux Chief Pex X PB couplings

http://www.siouxchief.com/products/supply/powerpex-systems/astm-f1807/adapters-connectors/straight/pb

JUGHNE

I believe that PB might be considered 3/8".
A piece of 3/8" OD ACR copper will just fit snugly inside my PB.
For me I needed 1/2 CTS X 3/8 CTS, I would have preferred the crimp transitions but could only find the "quick connect" design as noted above.