Cutting into pex for new basement bath

Old 07-31-18, 03:19 AM
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Cutting into pex for new basement bath

I just want to make sure I have all my bases covered before I start on this on the weekend.

I have a propex expander tool and all the proper fitting/pipe.

My question is the steps I should take before cutting into the existing water lines with the pex cutting tool.

I know I obviously need to shut the water off to the house, then open up the outside spigots and indoor sinks to drain the water/release the pressue.

With the HOT WATER line I am cutting into in the basement being lower than these spigots will I need to drain the hot water heater down a bit as well? My worry is that just opening the indoor sinks, outdoor spigots, etc. will not be enough and I do not want to cut into the hot water line and then have the entire water heater siphon out onto my basement floor.

Also, I know the lines will not be totally drained so is it ok to cut into these with the pex tool? Will I then need to cut then again for a "clean cut" after the reaming water in the lines is out before making the connection?

Thanks in advance for the advice.
Old 07-31-18, 04:53 AM
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When you cut the PEX tubing only the water above will drain out. If your water heater is located lower than the cut then it will not drain (the whole water flows downhill thing). If you close all the faucets and spigots after relieving the system pressure you can work fast and not drain the water lines. If you plan on taking your time getting that first fitting into the line then have a bucket ready to catch the water when you cut the line.

If your first cut into the water line is good then there will be no difference between it and any other cut. So, no need for a second "cleaning" cut.

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