Water dribbles out of shower head when filling the tub with diverter down

Discussion in 'Shower & bathtub Forum & Blog' started by badbeef1, Aug 16, 2011.

  1. badbeef1

    badbeef1 New Member

    Messages:
    3
    Location:
    Saskatoon
    Hello

    We just had our bathroom renovated and the plumber installed a new American Standard " cadet model 1675 " tub and shower set. When you turn on the tap to fill the tub some water runs out of the shower head even though the diverter is down.I called American Standard and they said that the distance from the centre of the valve body to the centre of the shower arm connection has to be a minimum 48 inches and even though it does not say that in the instructions that it is common plumber knowledge. Can somebody help me out here please? The water pressure isn't too high and the plumber says the valve body isn't installed upside down. I don't think they tested their installation and now the drywalling and tile is all complete and we have this problem. The contractor just came back last night and tore out the tile arnd drywall from around the manifold and thinks the issue is that the plumber has 3 elbows going to the diverter spout. Any other opinions? They also used some type of flex plastic pipe for all the connections to the manifold and at the lowest elbow changed from plastic to copper going to the diverter spout. I am also concerned about the repair job now to the drywall and tile and how it will meet the remaining tile and how this will be a weak point. I have some pictures that I can upload later as well.

    Thanks!

    Paul

    http://www.americanstandard-us.com/assets/documents/amstd/install/Install_2169.pdf
    Last edited by a moderator: Aug 17, 2011
  2. BobL43

    BobL43 DIY Senior Member

    Messages:
    1,786
    Location:
    Long Island, NY
    I am pretty sure when I installed my new Delta tub/shower valve and tub spout kit, the instruction said not to use plastic pipe from the valve to the spout as I remember. Too much restriction of flow to the spout in any manner will do a little of what the diverter does: make the water flow up the shower line, in your case just some.
  3. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    21,820
    Location:
    New England
    What's also troublesome is your mention of drywall in the shower area...this should NEVER be used in a shower (wet) area. CBU (cement board) should be used under the tile, and a vapor barrier behind that in a wet area.

    From the valve to the spout should be as straight as possible with 1/2" copper. Depending on the valve, some require a twin-ell fitting to then run to the showerhead, and some can use the upper (smaller - make sure it is the smaller one, generally on the top of the valve) directly to the showerhead. Having a full-sized supply to the spout and the smaller, restricted outlet to the showerhead is all it normally takes to make it all work.
  4. Terry

    Terry Administrator Staff Member

    Messages:
    14,794
    Location:
    Bothell, Washington
    The pipe to the tub spout has to be full sized.
    If they used PEX, which has a smaller diameter, it will force the water up toward the shower head.

    Also note that PEX fittings will further decrease the flow.

    The entire tub spout piping should have been done in either copper pipe and fittings, or threaded brass nipples and a 90.
  5. taz150

    taz150 New Member

    Messages:
    4
    Location:
    Florida
    Dribbling water

    Hi all,
    From the shower (hot side ,cold side and diverter on tub spout) I would turn on the hot and cold sides,and within a second or two water would dribble/flow weakly out of the shower head before the diverter in the tub spout was pulled up to shower mode. These things i did check if helps: All piping is 1/2" copper from shower valve to shower head, 48" from shower head to hot and cold assembly/valves. Could it possibly be the plastic diverter valve inside the tub spout? Any help with this would be greatly appreciated!

    Thank you
  6. Terry

    Terry Administrator Staff Member

    Messages:
    14,794
    Location:
    Bothell, Washington
    How about a picture of the valve and the tub spout piping.
  7. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    21,820
    Location:
    New England
    It's unlikely that it's the spout, but the quick way to check is to remove it then turn the water on.

    On some valves, you are only supposed to use ONE of the outlets, not both. Don't know if that applies to the unit you have. If it specifies only use one, the other needs to be capped, THEN, you use a twin-el to branch off to the showerhead and the spout.

    Have you measured your water pressure? If yours is over 80psi, this could happen. Industry standards call for the use of a PRV when the pressure exceeds 80psi.
  8. johnfrwhipple

    johnfrwhipple I love these ACO Shower Drains - Best in Class

    Messages:
    3,818
    Location:
    North Vancouver, BC
    Great post Terry. I have not heard this before until just today.

    If a mixing valve is piped then with pex is it wise to use 3/4" pex for the connection to the shower heads Wing Back fitting? Do you need to track down a 3/4" Wing Back?

    JW
  9. johnfrwhipple

    johnfrwhipple I love these ACO Shower Drains - Best in Class

    Messages:
    3,818
    Location:
    North Vancouver, BC
    Great post Terry. I have not heard this before until just today.

    If a mixing valve is piped then with pex is it wise to use 3/4" pex for the connection to the shower heads Wing Back fitting? Do you need to track down a 3/4" Wing Back?

    JW
  10. jimbo

    jimbo Plumber

    Messages:
    8,997
    Location:
    San Diego
    It is the connection from the valve to the SPOUT that will cause problems if you use 1/2" pex or cpvc. I guess you could use 3/4. Probably easier to do it in 1/2" ips brass pipe, or 1/2" copper
  11. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    26,285
    Location:
    Cave Creek, Arizona
    Do NOT use ANY PEX, and make the connection as straight as possible. Turns will cause back pressure just like PEX will, and using PEX with ELBOWS would be the worst possible connection.
  12. badbeef1

    badbeef1 New Member

    Messages:
    3
    Location:
    Saskatoon
    Thanks for all the replies. Turns out the plumber used 3 elbows from the manifold to the diverter spout with the first 2 sections between the elbows containing pex. My daughter had commented that it seemed to take a long time to fill the tub. They came back and corrected it but I am not too happy about the tile and cement board being ripped out and then patched up on a new install to begin with. I'l attch a pic of the waterproofing as well for some opinions.

    Attached Files:

  13. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    21,820
    Location:
    New England
    The WHOLE thing from the valve to the spout HAS to be made in copper or brass or you will continue to have that same problem.
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