DIY Home Improvement Forum banner

1 - 9 of 9 Posts

·
Registered
Joined
·
39 Posts
Discussion Starter #1
On the other side of my mechanical room's wall, we are putting in a small powder room. The sink is going to be on the wall below the boiler valves, which is represented by my awesome graphic. I was hoping to just pop the drain through that wall and down to the current ABS drain line in the photo. The drain just services the boiler and the hot water tanks relief valve, so hopefully never used besides testing the valve. The slope is adequate from there going to my stack.
  1. Would this be appropriate to do?
  2. Should I have a little trap on the bottom of the vertical pipes coming down from my tank and boiler? I was once told I should, but these would be dry since those relief valves hopefully aren't releasing water often. So, would that do anything?
631217
 

·
Registered
Joined
·
5,281 Posts
Imo, you should fix that pressure relief valve drain to include a ptrap if you are going to plumb it like that.

Yes, you need a Ptrap constantly filled with water for seal. Don't you smell the sewer gas in the basement?? The sewer gas is basically venting in your basement between your boiler and wh.

Most basement wh's have the pressure relief valve piped into floor drain, right on floor, outside, or wh drain pan piped outside or floor drain.

In regards to your new powder room, how do you plan to vent the sink? Studor/aav valve??
 

·
Registered
Joined
·
1,875 Posts
1. What you propose is an S trap, and would need a vent (or an AAV, if allowed in your city).
2. Now, what's wrong with the T&P drain? It must be rigid pipe all the way to the exterior of the house, and not ABS pipe. Remember, if it activates due to temp, a plastic pipe won't be able to handle the hot water.
 

·
Registered
Joined
·
39 Posts
Discussion Starter #4
Imo, you should fix that pressure relief valve drain to include a ptrap if you are going to plumb it like that.

Yes, you need a Ptrap constantly filled with water for seal. Don't you smell the sewer gas in the basement?? The sewer gas is basically venting in your basement between your boiler and wh.

Most basement wh's have the pressure relief valve piped into floor drain, right on floor, outside, or wh drain pan piped outside or floor drain.

In regards to your new powder room, how do you plan to vent the sink? Studor/aav valve??
No, in 5 years of living here we have never smelled any sewer gas. 20 yrs ago when the remodel of the basement was done, they never did a floor drain there. So, that is why it isn't piped into the floor. Studor valves are allowed in my area, so that is how the sink will be vented. So I really just need to figure out the best way to drain the sink, which could be to run all new pipe parallel to the pipe that is there, but that seems redundant to me.
 

·
Registered
Joined
·
39 Posts
Discussion Starter #5
1. What you propose is an S trap, and would need a vent (or an AAV, if allowed in your city).
2. Now, what's wrong with the T&P drain? It must be rigid pipe all the way to the exterior of the house, and not ABS pipe. Remember, if it activates due to temp, a plastic pipe won't be able to handle the hot water.
I would be doing a P trap by having a horizontal pipe running into the current line. Not a downward vertical line like my bad illustration shows. The vertical drop would be less than 24" before going horizontal into the current ABS pipe.
 

·
Registered
Joined
·
5,822 Posts
Is the pipe your connecting to even connected to a drain and not going to a floor drain. WMB min size is 2 inch and must be vented .
 

·
Registered
Joined
·
39 Posts
Discussion Starter #9
Is the pipe your connecting to even connected to a drain and not going to a floor drain. WMB min size is 2 inch and must be vented .
That pipe connects into the waste line from upstairs, before dropping into the ground. It does not connect to into the stack from what I can tell.
 
1 - 9 of 9 Posts
Top