I have a sump pump pumping up 1.5″ ABS about 5 feet, then 90 degrees to the outside where it will dump into a 4″ PVC running underground away from the house (if I manage to finish it tomorrow).
I was thinking about sticking in a backflow preventor in the horizontal branch, not so much to stop the water – cause I don’t think its needed for that- but to stop insects getting in. However, I’m concerned that in winter it may freeze up since in the outside wall of an unheated food storage cantina – [I’m in Toronto, Canada]
Edited 7/1/2009 1:43 am ET by BobRat
Replies
If you put in a check valve, the section of the pipe that holds water may freeze up.
With no check valve the water will drain back through the pump, and may offer some protection against freezing.
When water is in motion it's far less likely to freeze.
At the top of your vertical pipe, make sure you have enough fall so the water gets away quickly and doesn't lay in the pipe.
I haven't dealt with that many sump pump situations, but I don't recall any problems with bugs entering via the pipe.
If you decide to use the check valve, install the it in the vertical indoor section. Horizontal swing checks do not close as readily as those in the vertical because the vertical installation always has a head of water above it to force it closed.
Have the transition to horizontal high enough to always drain the horizontal piping by gravity so that the piping outside drains with each cycle.
dont tell Mcguinty or hell put a tax on it !
I'd like to put a backflow preventer on him, but I'm too busy digging holes to put my garbage in