issue with "step in spa" part of inbound pool

[kshinester]

new to this have done a fair bit of research but no expert
we have a 25 yr old but excellent inground kafka I believe liner pool with a "step in spa" as part of it
it seats about 4 has its own intake and outbound lines that "mix" at the pump and heater so it can be run as a stand alone or on combo with the pool
for the last several years have always had issues getting the spa part working as water has tended to come "up" the venturi inlet on the top.....but now the issue isn't stopping
spa has 2 water collection ports that drain to the pump/heater at the bottom and 4 inlet jets, 3 near the top and one at the same level near the bottom as the water collection ports.
water will poor out of the venturi hole at the top and i can't close it off...I guess i could try to plug it but it has a threaded pvc tubing that the screw won't close fully..... the only way now to
prevent water coming OUT the venturi is to remove one of the UPPER jets that screw in completely and essentially allow theatre to come out with "less" pressure.... if i just open the jets or remove the lowest jet, water still comes out the venturi.....
we aren't "losing" water but Im guessing there is a broken venturi connection ????) are these supposed to act as one way valves ???
its all ingrained and under concrete and I'm not sure anything is accessible from outside the spa component

any and all explanations and advice is appreciated

thanks

 

[Richard320]

Sounds like a clog in the lines after the venturi.

Seen it here before. I think the last guy discovered a chunk of concrete or mortar that some slob got in the pipes when it was built finally worked it's way down.

Use the search box for "Clogged Venturi" and you'll find lots of older threads about the issue. It saves me a lot of typing.

 

[kshinester]

Thank you very much
im going with the working diagnosis of broken jets or at least jets that don't function as designed.
I have searched as you suggested and found the jets we have. The ones we have have some cracks and seals are gone so perhaps the issue is as simple and they just don't entrain air via the Venturi pipes anymore so I've ordered four and will replace them. It's a cheap way to start as they were $13 each. If this doesn't work I'll take it from there
These are the jets

Waterway Spa Poly Jet 210-6097 Deluxe Scallop Face Roto Gray