I need to replace a Roman Tub faucet with handshower. I have 3/4 " supply lines. Do I have to have 3/4NPT threaded inlets or can I use a unit that has 1/2" IPS inlets? The 1/2" unit is half the price.

Go for the 1/2" one. There will be no loss of pressure or volume. Or you could keep the valve and purchase a tub spout with a hand held shower outlet. Good luck, Tom

Hmmm... I'm not so sure without a little more info...

If you have a 3/4" valve in place now I would replace with the 3/4" valve IF you want the tub to fill as fast as it always has. If you don't care how fast the tub fills or you need to save the money then 1/2" will also work fine... may just fill tub slower as I have said!

Mark

Thank you. I'll go with the 3/4.

[QUOTE=Redrivers;3465538]Thank you. I'll go with the 3/4 inch Roman Tub/handshower>

It's not very often I disagree with Mark but my code allows three fixtures on a 1/2" branch, I can see no difference in coming off a 3/4" main and installing a 1/2" valve then going 3/4" all the way. Perhaps a small lose of volume but not of pressure. If it were my call I'd go with the less expensive 1/2" valve. I can see no advantage in increasing the size of the valve to 3/4" except the added expense, Regards Tom.

Hi Tom

If you've ever filled a large/deep hot tub with a 1/2" valve VS a 3/4" valve with 3/4" pipes you'd remember the difference in fill time... it can be quite dramatic!

In this case, Redrivers has decided he wants fast fill time over cost savings and I think he made the right decision!

Have a good day!

I have to agree with Mark on this. However I will note that I have seen "3/4" valves that were restricted down on the internal portion of the valve assembly to less than that of what a good high volume 1/2 roman tub fuacet is. You really want to look at the gpm ratings with these type of fuacets. Normally you will be best off with a good 3/4, but sometimes a high volume/fast fill 1/2" faucet will do the job. A lot of this will also come down to what your water pressure is.