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Thread: Spa problems

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    Spa problems

    I have a gunite pool with a spa. The pool is about 5 years old. When the pool was new, the water pressure coming from the spa jets was very strong. The spa would heat up in minutes. Over the last few years, the pressure from the jets became very weak. When the spa is turned on, you can't see a ripple on the spa water surface due to low pressure. The pressure increases if I run the air bower and then shut it off. 3 pool companies have no idea why this is happening. I'm thinking about swaping out my 2hp motor for a 3hp, but I don't think this is the problem. Anybody have any ideas?

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    Mod Squad JohnT's Avatar
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    Re: Spa problems

    Can you provide more details about your system? Are the controls automated or manual? What kind of filter, pressure gauge readings

    Generally, lower flow someplace means one of two things. Either the water is going someplace else like into the pool instead of the spa, or there is a problem with water getting to the pump so there isn't as much being delivered.
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    Re: Spa problems

    For a concrete hot tub there are usually plastic jet assemblies where the return pipe comes through the wall. If you have this type of fitting there should be a nozzle and a metal escutcheon. If the nozzle is missing the pressure will not feel right. The fitting will also have a venturi air injector that can be connected to a blower or to air inlets.

    You do say "The pressure increases if I run the air bower and then shut it off". When the system is off the air line can fill with water. When the pump turns on the venturi should start pulling in air, but it may not be able to clear the water in the line. If the blower is connected to the venturi air inlet it pushes the water out of the line, and once it is clear it continues to work.

    The air injection increases the feel of the pressure. If there is a blower it is usually designed to be run with the jets.

    1) Are the nozzles all in place?
    2) Are there any air inlet controls in the deck near the tub?
    3) Is there a separate pump just for the jets?
    4) What is the Horsepower of the jet pump?
    5) Is the pump operating properly?
    6) How many jets are there?
    7) Does the pressure seem right after the blower gets the air started?

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    Re: Spa problems

    Quote Originally Posted by PoolOwnerNumber9
    For a concrete hot tub there are usually plastic jet assemblies where the return pipe comes through the wall. If you have this type of fitting there should be a nozzle and a metal escutcheon. If the nozzle is missing the pressure will not feel right. The fitting will also have a venturi air injector that can be connected to a blower or to air inlets.

    You do say "The pressure increases if I run the air bower and then shut it off". When the system is off the air line can fill with water. When the pump turns on the venturi should start pulling in air, but it may not be able to clear the water in the line. If the blower is connected to the venturi air inlet it pushes the water out of the line, and once it is clear it continues to work.

    The air injection increases the feel of the pressure. If there is a blower it is usually designed to be run with the jets.

    1) Are the nozzles all in place?
    2) Are there any air inlet controls in the deck near the tub?
    3) Is there a separate pump just for the jets?
    4) What is the Horsepower of the jet pump?
    5) Is the pump operating properly?
    6) How many jets are there?
    7) Does the pressure seem right after the blower gets the air started?
    1. There are no nozzels in the jets, just a flow direction ball. Never was anything in them.
    2. No air inlet controls.
    3. No, same pump as the pool.
    4. 2HP
    5. It seems to be, no problems with the pool.
    6. 8
    7. Better, but not like it was a few years ago.

    We usually don't use the blower, never did. Now we just use it to get things going then shut it off.

    You can stick your finger in the jet while the spa is on and feel there in nothing in there, when you do that the spa pressure drops to almost nothing, like it was shutting off.

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    Re: Spa problems

    Quote Originally Posted by JohnT
    Can you provide more details about your system? Are the controls automated or manual? What kind of filter, pressure gauge readings

    Generally, lower flow someplace means one of two things. Either the water is going someplace else like into the pool instead of the spa, or there is a problem with water getting to the pump so there isn't as much being delivered.
    I have automated valves, pentair DE filter and the gauge is at about 18 after a backwash.
    Wouldn't the pressure change if there was a restiction in the spa lines?

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    Re: Spa problems

    There are a few things I think it could be.
    1) Clogged suction lines to the hot tub.
    2) Clogged return line to the hot tub jets.
    3) Automatic valves not functioning properly. Possibly only switching part way.
    4) Pump is going bad.

    1) If it is a clogged suction line, the pressure on the filter will go down when the system is switched from pool to hot tub.
    2) If it is a clogged return line to the hot tub jets, the pressure will go up when the system is switched from pool to hot tub.
    3) If the automatic valves are not switching all the way, there will still be suction and pressure at the pool suction and returns when there should be none. And the level on the hot tub will probably go up or down.
    4) Check the impeller, flow rate, voltage and current.

    If there are separate automatic valves for the pool and hot tub, instead of combination valves, the valves to the hot tub may be causing the problem with no effect at the pool.

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    Re: Spa problems

    Quote Originally Posted by PoolOwnerNumber9
    There are a few things I think it could be.
    1) Clogged suction lines to the hot tub.
    2) Clogged return line to the hot tub jets.
    3) Automatic valves not functioning properly. Possibly only switching part way.
    4) Pump is going bad.

    1) If it is a clogged suction line, the pressure on the filter will go down when the system is switched from pool to hot tub.
    2) If it is a clogged return line to the hot tub jets, the pressure will go up when the system is switched from pool to hot tub.
    3) If the automatic valves are not switching all the way, there will still be suction and pressure at the pool suction and returns when there should be none. And the level on the hot tub will probably go up or down.
    4) Check the impeller, flow rate, voltage and current.

    If there are separate automatic valves for the pool and hot tub, instead of combination valves, the valves to the hot tub may be causing the problem with no effect at the pool.
    Isn't there always a rise in pressure when the spa is on?

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    Re: Spa problems

    I have no pressure change from pool vs. spa.
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    Re: Spa problems

    "Isn't there always a rise in pressure when the spa is on?"
    It might go up. If that's what it has always done, then that's OK. If that's something new, then it could indicate a problem. What is the pressure reading when the system is on Hot Tub? Is this a two speed pump?

    You have a 2 HP pump; that should deliver about 85 to 145 gpm (avg. 115), depending on the pressure. You have 8 jets; that makes it about 10.6 to 18.1 (avg. 14.4) gpm per jet, which is right for some jets. Since this is a new problem on a system that was working fine, we will assume that the design is correct.

    When the system is on the Hot Tub, is there any suction at the pool skimmers; or is there any pressure at the pool returns?

    Are the automatic valves working properly? As they get old, they need to be serviced (lubricated) periodically. They may be getting stuck and only opening part way, which could restrict your suction or return to jets.

    You could also remove the directional eyeballs in the jets to look for missing or worn parts. Sometimes the gaskets get worn out. There will be screws or a threaded retainer ring holding in the eyeballs. Remove all of the eyeballs, run the system and note any debris coming out of the jets, also check the pressure with the eyeballs out.

    Also, there is a check valve on the outlet of the blower that may be sticking. If it is not working properly it could limit the air intake of the jets, which would reduce the pressure feeling of the jets.

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    Re: Spa problems

    Thanks for the replys. I'll check everything suggested. Does anybody know where to buy new jets?

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