Price Pfister series 8 Shower valve question

Discussion in 'Shower & bathtub Forum & Blog' started by shadysprings, Jan 7, 2010.

  1. shadysprings

    shadysprings New Member

    Messages:
    28
    Location:
    Los Angeles
    I have three showers on the 2nd floor of house. Water pressure at regulator is 65 psi. In each bathroom, the tub and faucets have water pressure and flow like a rocket engine. But all three showers right next to tubs have much reduced flow.
    I took off shower heads, changed the pressure balance cartridges, replaced the valve stem assemblies, but still the same.
    The water just runs weak.

    I think this Price Pfister single handle shower is a real common tract home valve.

    Does anyone know if this is normal? Is there a way to adjust or modify the assembly to increase flow through it?

    Thanks
  2. Most of those valves are ported down to 3/8".


    Take the cartridge out, get a bucket and let the water shoot through the open valve. If the flow is still substantial, and even new cartridges didn't change the flow rate, it's most likely the valve's issue with flow restriction.
  3. shadysprings

    shadysprings New Member

    Messages:
    28
    Location:
    Los Angeles
    I just took the cartridge out and had the wife turn on the water supply for 5 seconds while I watched the flow. It's definitely not a problem up to the valve. In 5 seconds, it flooded the shower stall and had 3" of water that took another 20 seconds to drain out.

    The cartridge is brand new and everything is installed exactly as shown on diagram. And all three showers do the same thing.

    So what could it be? Am I SOL?

    Thanks
  4. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    26,631
    Location:
    Cave Creek, Arizona
    showers

    IF the hot and cold pressures are not almost equal, the flow from the higher pressure side will be reduced to the level of the other one, which WILL reduce your flow. One possible problem is the internal porting of the valve. The port to the shower is much smaller than the one for the tub side, which is why I usually install the valves inverted and rotate the cartridge to keep the hot and cold sides intact.
  5. shadysprings

    shadysprings New Member

    Messages:
    28
    Location:
    Los Angeles
    "higher pressure side will be reduced to the level of the other one" is this simply because the user of shower would adjust the water temp manually and would turn towards the side with less pressure to keep it balanced? Or does the cartridge have some kind of built in regulator?

    "I usually install the valves inverted" this sounds like a real interesting idea. Does it require removing the whole valve assembly. I assume this means I need to demo some wall to get to the valve. Since my shower is a stand alone stall with no tub, does the valve still have the tub "stuff" on it?

    Thanks
  6. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    22,003
    Location:
    New England
    Pressure and volume are two different things. A pressure-balance valve doesn't care about the volume, it only cares about the supply pressure. When there is flow, if the pressure isn't even between the SUPPLIES, the balance spool will start to close off the higher pressure side to try to balance the relative flow rates. It is all about balancing the relative flow so your temperature doesn't change if say the toilet is flushed. the reduction in pressure, decreases the hot flow to keep the relative temperature of the mixed output about the same. If the pressure on one side is significantly lower than the other, the total flow and pressure will be decreased through the valve. You can only get max flow if the PRESSURE is the same on both the hot and cold inlets.
  7. shadysprings

    shadysprings New Member

    Messages:
    28
    Location:
    Los Angeles
    So does the pressure balance cartridge also restrict flow to 2.5g? There's something in this cartridge significantly reducing flow. Since I have an extra one, is there a way to bore it out to test if it is the cartridge?
    [​IMG]

    In case the image doesn't show, it's a Price Pfister 274-291 Pressure Balance Cartridge
    Last edited: Jan 8, 2010
  8. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    22,003
    Location:
    New England
    What are the inlet port diameters? Look at the spec sheet to see what the flow rate is supposed to be at a certain pressure. I doubt it is as low as 2.5gpm. But, if there is any debris in one side, it could be. Also, the spool valve must be free to move. If it is jammed or stuck, the flow could be compromised.
  9. shadysprings

    shadysprings New Member

    Messages:
    28
    Location:
    Los Angeles
    I've been researching this and it appears that all new showers and for the past years now do limit flow by law/code. i though it was the shower head that limited it to 2.5g but it appears the valve and cartridge setup limit it. So even with the shower head unscrewed off, the flow will still only be 2.5gal.

    Does anyone know if this is true? I think it's absolutely ridiculous that there some government agency dictating how much water I use to take a shower with. i pay for the water and the more I use the more i pay. That's self limiting in itself.

    I am the only one that enjoys a nice full flow shower at the end of a long day?

    I've noticed that all the faucets I've bought recently are all low flow as well. Now it takes 10 minutes to fill up a pot with water!! Sheez, what's next??
  10. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    26,631
    Location:
    Cave Creek, Arizona
    flow

    The flow rate is restricted at the shower head. The components of the valve MAY restrict it also, since all it has to do is flow the 2.6 gpm, but they seldom do it, because the flow is unrestricted when that same valve is used for a tub. DO NOT try to modify the balancing spool. You will destroy it. IF you have access, one thing you can do without removing the valve is to connect a pipe to the bottom/tub port, route it upwards, and connect it to the shower riser with a tee inserted above the valve.
  11. shadysprings

    shadysprings New Member

    Messages:
    28
    Location:
    Los Angeles
    Thanks. I may give that a try. I use this shower stall to also fill up a tub for washing an infant. I have a diverter valve with a hose attached to fill up the tub. You can imagine how long it takes with low flow.
  12. shadysprings

    shadysprings New Member

    Messages:
    28
    Location:
    Los Angeles
    Forgot to ask. So I would connect the bottom port to the shower "up" pipe. Then cap off the top port now being used?
  13. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    22,003
    Location:
    New England
    Valves that have two outlets, the top one is often a smaller port than the bottom one. So, cap the top one, and reroute everything from the bottom one to get the max flow possible. there is no reason to have the top port large (in most cases), since it doesn't need to supply much volume as most people use a single showerhead. Filling the tub, on the other hand, doesn't need any restrictions, and they uusally make that port as large as they can given the supply lines. If you want max volume, your supply lines and valve would need to be larger (say 3/4" or larger).
  14. shadysprings

    shadysprings New Member

    Messages:
    28
    Location:
    Los Angeles
    On the PP 0X8 valve, doesn't the water go through the pressure balance cartridge regardless if it's diverted to the shower or tub?
    I notice there's only one outlet hole inside the valve.

    I'm also wondering if there are any cartridges that fit this valve body that are not pressure balancing. Just straight through. Then the show head can control flow.

    Thanks
  15. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    22,003
    Location:
    New England
    When the valve is configured for a shower or tub/shower, in the USA, it must have anti-scald technology. This is most often provided by a pressure balanced valve. There's no way around the anti-scald if you want to pass an inspection. that doesn't mean you can't buy older designs - it is okay to repair an older valve, but replacement requires the new code compliance. If it is a tub only, no anti-scald is required. If a valve has two outlets (not all do), the one going to the shower will often be smaller since it doesn't typically need as much flow as filling the tub. Many have two outlets but say you must plug the one not used. this means you need a twin-el connection to feed both the tub and shower. how you divert or control the flow between them is up to you. Most common is a diverter spout, but separate valves work as well.
  16. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    26,631
    Location:
    Cave Creek, Arizona
    valve

    Either cap the top one or connect to the pipe with a tee and use both openings.
  17. shadysprings

    shadysprings New Member

    Messages:
    28
    Location:
    Los Angeles
    Thanks jadnashua for the explanation.

    and hj.
    Using both ports with a tee? Now that's one great idea. Genius. OK,
    I'll be getting back on how that works out. But it won't be for awhile. Gotta do some tile and concrete removal first.
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