Installing black water holding tank
We are installing a new black water holding tank and toilet in our TT. The tank is 26x62x7....3" drain and 1" vent. What fittings/grommets will we need for installation?
Forum Discussion
you might have to wait until the old tank is down before you can figure out the fittings on the top. I would definitely look into whether the manufacturer can or does provide the tank with the 3" drain already plumbed to a flange. I believe the tanks mostly are side or center drain so hopefully it can be purchased that way. As far as the toilet or vent pipe openings, those are going to have to be measured and cut on site. On mine I glued the fittings on with standard ABS glue. I let them cure for a week before I even thought about installing the tank.
Hopefully your tank comes with the fittings, if not I would use one of these glue on fittings instead of a rubber slip in fitting for the vent. Something like this fitting has a little flange at the bottom so the vent pipe can't slip down into the tank.
Here's a few pointers that I would suggest based on my ONE black tank replacement.
Take a digital picture of the sensor wiring or take good notes.
After you remove the toilet and the flange screws from the floor, the flange most likely screws into the top of the tank. Use a hammer and punch to get the flange turning and unscrew it.
Go up on the roof and remove the vent cap add make sure the vent pipe is free to slide up and down. If it's glued to the tank, it's going to need to come down as the tank comes down.
A new piece of 1 1/2 inch black ABS pipe is only a few bucks at Home Depot. If your vent is just a straight pipe then just hacksaw the old one off and replace with a new pipe.
The flange hole is 4" I bought a $15 hole saw kit from Harbor Freight for this task. Kit
Measure 10 times, you only get to cut once.
Cut the toilet hole first making sure it is far enough away from the edge of the tank that you can mount the flange. Maybe mount the tank and verify the location or mark the location through the hole in the bathroom floor. BUT take the tank down to do the cut. This way can can make sure you're not going to drill right into a corner of the tank or something. I didn't do this and it was close enough to make me remember this tip.
I would glue the toilet fitting on the tank and mount the tank under the floor making sure to center the tank opening under the hole in the floor. Then figure out a way to mark or verify the vent location.
One thought would be to dust the top of the tank in the vent location with baby powder and mount the tank. Then drop a few drops of water from the center of the opening in the roof to land in and mark the powder.
Or maybe you can drop a plumb bob down the vent hole and mark the center of the vent.
Glue the vent flange on the tank and let it dry before installing the vent pipe. On mine I lifted the tank into place and my neighbor lowered the new vent pipe down from the roof. I then snaked my hand up on top of the tank with the ABS glue and smeared it into the fitting and slid the pipe in. I then cut the extra length off the pipe from up on the roof.
Those are the things I can think of. Good luck
Hopefully your tank comes with the fittings, if not I would use one of these glue on fittings instead of a rubber slip in fitting for the vent. Something like this fitting has a little flange at the bottom so the vent pipe can't slip down into the tank.
Here's a few pointers that I would suggest based on my ONE black tank replacement.
Take a digital picture of the sensor wiring or take good notes.
After you remove the toilet and the flange screws from the floor, the flange most likely screws into the top of the tank. Use a hammer and punch to get the flange turning and unscrew it.
Go up on the roof and remove the vent cap add make sure the vent pipe is free to slide up and down. If it's glued to the tank, it's going to need to come down as the tank comes down.
A new piece of 1 1/2 inch black ABS pipe is only a few bucks at Home Depot. If your vent is just a straight pipe then just hacksaw the old one off and replace with a new pipe.
The flange hole is 4" I bought a $15 hole saw kit from Harbor Freight for this task. Kit
Measure 10 times, you only get to cut once.
Cut the toilet hole first making sure it is far enough away from the edge of the tank that you can mount the flange. Maybe mount the tank and verify the location or mark the location through the hole in the bathroom floor. BUT take the tank down to do the cut. This way can can make sure you're not going to drill right into a corner of the tank or something. I didn't do this and it was close enough to make me remember this tip.
I would glue the toilet fitting on the tank and mount the tank under the floor making sure to center the tank opening under the hole in the floor. Then figure out a way to mark or verify the vent location.
One thought would be to dust the top of the tank in the vent location with baby powder and mount the tank. Then drop a few drops of water from the center of the opening in the roof to land in and mark the powder.
Or maybe you can drop a plumb bob down the vent hole and mark the center of the vent.
Glue the vent flange on the tank and let it dry before installing the vent pipe. On mine I lifted the tank into place and my neighbor lowered the new vent pipe down from the roof. I then snaked my hand up on top of the tank with the ABS glue and smeared it into the fitting and slid the pipe in. I then cut the extra length off the pipe from up on the roof.
Those are the things I can think of. Good luck
