Delta Universal Shower/Tub Valve Body Rough-in : Capped tub nipple question

I have new construction (I am the HO/GC). The building is a summer camp and heat will be off during much of the winter. The plumbing is done and all nicely pitched to drain valves in a few locations. I recently discovered one little place that water will not drain.

I have capped off the bottom nipple (the one that would connect to the tub, if I had a tub), and water will not drain from there when I drain the system.

Is is ok for water to freeze in there? Is the volume small enough and the fixture strong enough to not crack the fixture?

Shower tile is on and the backside of wall is finished too. I can conceivably get in through the backside (perhaps to replace with a 3-nipple version? Does such a thing exist?), though not without some expense.

Here's a picture of the unit I'm talking about:

I have put a tub spout in a stand up shower as a foot wash,but yes that little bit of freezing can damage the faucet.

gr88 said:

Is is ok for water to freeze in there? Is the volume small enough and the fixture strong enough to not crack the fixture?

Click to expand...

Winterization is a pretty imprecise science...
It all comes down to luck...

Initial installs often take several years of testing and redesign on problem areas to achieve perfection...

And then after that there is always that year some fluke happens and you need a repair...

Any water left behind can freeze and cause damage... Maybe....

Well do you feel lucky?

I think I'd just put a spout on it, as noted, it will let you get the water just the right temp before you switch to the showerhead, and, it will drain the water in the shower riser so you don't get that cold spurt when you next turn it on during normal operations from the water trapped there.

To be sure I would remove the cartridge after draining.

John

water has to be trapped so it cannot freely expand in order to "break" things. That little bit of water is free to expand into the faucet body, and the shower riser prevents any pressure build up. I would not worry about it, IF you make sure all the other water is drained from the riser and valve body..

That "Dirty Harry" line saved the .44 Magnum from extinction, because they had already decided to drop it. But then EVERYONE wanted the "most poweful handgun" and sales went over the top.

As long as you can get enough out of the valve and riser... Hence the do you feel lucky...