This is my stupid question of the day. I have two old gate valves for my washer that I would like to replace. They are probably from the early 80s, and the cold water side has started to leak. I had repacked the valve and then tightened the packing nut. That worked for a while, but it has started to leak again. My question is that I can't tell if they are 1/2" or 3/4" valves. I'm surprised that I can't tell this by looking, but I don't do a lot of plumbing. I was planning to order Dahl valves from SupplyHouse (made in Canada). I was trying to find something made in America, but I couldn't locate anything. I can tell that the copper coming out of the wall is 1/2". What's throwing me off is that the threaded outlets on the tee (for the water hammer arrestor and gate valve) look larger than the inlet. I don't know if this is because they are threaded and it makes them larger, or if that's because they are actually 3/4". I've posted a picture, but it's hard to see the size difference that's noticeable when you look at it. I guess I could always shut the water off, unscrew the water hammer arrestor, and figure it out that way. Just not sure if there is an easier way. On a side note, should I also be changing the water hammer arrestors? I am planning to swap out the old rubber hoses with braided stainless. [img]https://cimg0.ibsrv.net/gimg/www.doityourselft.com-vbulletin/2000x1504/img_4249_1__73496a219c89b6fb32db4f159c90a4804f9f918f.jpg[/img]

Hello all, I have a bit of mystery and looking for plausible explanations... I have a typical/small 1960's bi-level. The whole waste system I think is pretty simple. Upstairs I have kitchen, full bath, and smaller master full bath with shower stall. Downstairs I have a 1/2 bath and laundry room. The main waste stack appears to be 3" copper pipe, drains out to a septic about 10' or so from the house. It doesn't happen all the time, but often enough when someone flushes a toilet upstairs or takes a shower, the toilet down stairs bubbling from some kind of back pressure. I've never observed any system issues when the laundry room is used. I am not sure how this came to be. When I bought the house in 2004 everything seemed to work fine. At that time I lived alone. I never used the downstairs bathroom much at all, and noticed over the years that the flushing got slower and slower. Eventually had a family that increased load on the upstairs water use. The only changes I ever made to the house was to replace 1 toilet upstairs with low flow, and re-do the shower stall; at the time that was done, everything in house seemed to work fine. Come pandemic time I started working from home and using the downstairs bathroom more often. The slow flushing has been getting better over time, but I still notice the bubbling when shower/toilet is happening upstairs. I have no way to know for sure but I suspect maybe the waste stack is occluded somewhere just enough to allow water in the 3" wide pipe to back up and create the pressure needed to force that downstairs toilet to bubble up. Not sure what to do about it. I am thinking maybe get a plumber here to roto-rooter the whole waste stack out to the septic. Any thoughts or advice appreciated. Thanks! -- J