Time to get my PEX materials for plumbing the new addition on my house. It won’t be a lot to do, kitchen and bath right next to each other and a couple of outdoor spigots through the basement.
The big choice is the clamps or rings. Rings cost less, but it’s not a significant amount of money. Seems the clamps are supposed to be what the pros use (confirmed by my observations so far), the rings easier to install and the choice for DIYers, but I’d think the clamps must be better somehow or the pros would use them too. Any Straight Dope on that topic? Do crimp rings fail more often or something? What is the difference?
Any advice on manifolds? Seems like everything will be a lot easier to run individual lines from one big manifold for the kitchen and bath. I’ll need 5 hot and 6 cold lines for the kitchen and bathroom, there are several combination hot/cold manifolds that can handle that. All existing plumbing is 1/2" already, I see a lot of manifolds with 3/4" inlet and 1/2" outlets. If I used one of those I’d just need a 1/2" adapter on the inlet anyway, does it matter if I use 3/4" or 1/2" inlet to a manifold if the supply is only 1/2" anyway?
I love working with PEX. For general home use, I use the crimp rings because they are compatible with almost everything, the tooling is not expensive, and once crimped, I know the joint is secure. Clamps are very good, but it is possible to overcinch them, and end up damaging the clamp or the pipe. For professional work, I love the ProPex system… much more expensive tooling, and pipe, but very very very fast.
PEX is cheap. If you can do it, definitely go with a manifold. When I re-plumbed my house, I used one of these . I still put individual valves at the termination points (of course), but I love having a single place to isolate absolutely anything (or everything) if needed. The manifold also allows you to easily run new lines without interrupting service to anything else.
I was just looking at the Viega manifolds on their website. That looks great, and I will end up using the extra ports I’m sure.
Now I’ll have to check out the ProPex too, the manifold will reduce the number of connections a lot. You mention more expensive pipe, it’s not the standard PEX tubing then? I wonder if I can rent the ProPex tool.
Looking at the compression fittings for those that looks like a good system. I guess I could use those at the terminations too. I’ll have rigid pipe with a valve at each termination anyway, and with a big manifold there won’t be any intermediate fittings. This is looking easier than I thought, the additional cost of the compression fittings won’t matter at all.
It’s a type of tube that you stretch with the heated tool, then put the fitting in and it shrinks around it. We borrowed our neighbor’s tool to do our house with that, and it’s nice but I don’t think it’s a huge deal vs the traditional rings. Our next house, we’ll probably just do all crimp rings, adds maybe 5 seconds per fitting, and you can get all the stuff at big box stores.
I think I’ll use most compression fittings for now if I use a manifold with the adapters like the one above. With that manifold the only other fittings will be at the rigid pipe terminations, and I’ll put my termination valves on the rigid pipe above the floor. Any odds and ends I’ll just use the rings. I need to replumb the old house when I’m done and I’ll probably just get another manifold for that and do the same thing. I may not even need any other fittings with this approach. The tube is so inexpensive I don’t care how many lines I need to run, and every goes through the basement and up through the floor there also.
A 3/4" inlet line will be able to handle the full flow of 2 of the 1/2" lines without a drop in pressure. That whole “pi R squared” thing from high school geometry. Lack of cold water flow was what caused the hot water blast in the shower when someone flushed back in the olden days. From the hot water manifold, I’d circle a 1/8" line back through a check valve into the drain port of the water heater unless you plan on point of use water heater. This would provide hot water to the manifold 24/7 so less time is wasted waiting for hot water.
Expansion method all the way. Better pipe, better joints. Uponor is what most plumbers I work with use. Having a powered expander is a huge advantage though. Manual expansion is tough, if I had to choose that I’d probably just go with crimps.
Not too long ago I was working part as a part time service plumber. I used the Oetiker ear clamp system, here is a link to their site: http://www.oetiker.com/ I used those ear clamps with this tool: http://www.zurn.com/products/pex-cross-linked-polyethylene/plumbing/tools/qcrtqcrm, It’s a ratchet type crimp tool. The tool is much smaller than the ring clamp tools which need long handles to create enough force to make the crimp. The tool goes in places where it’s difficult to get the crimping end or the ring crimp tool because the tool only has to grip the ear on the ring. This particular tool also has a signal light that comes on when the crimp is complete.That and I only carried one tool. not two. Do not be fooled by the combo tools that have both 1/2 CTS* and 3/4 CTS sizes, there will be so many places that you will not be able to get the 3/4 CTS size into.
Oh I noted prices in the $150, $160 range. I reasonably sure I paid less than $20 at a big box. Same tool as far as I can tell by looking at pictures.
*CTS means Copper Tubing Size. Not all PEX is is CTS but depending on where you are that’s the most likely size.
Professionals use the expansion method because it’s faster when using professional tools. And time is money to a professional. As far as I know, both methods work fine if properly done*, and both are acceptable to code inspectors.
*‘when properly done’ is critical. Rings probably fail more often, just because they are done by amateurs, who often don’t know how or aren’t careful enough to do it right.