Spa leaks internally when jets are turned on

[krick]

I'm having an issue with my spa where it leaks internally when I turn on JETS #1. I've linked a photo showing where the leaks are as well as a short video link showing the blast of water past the couplings when I turn on the jets. It doesn't leak when JETS #2 are turned on.

Any thoughts on what the problem could be and where I should start looking to fix it?
I'm not sure if it's just the coupling seals that are failing or if there's an issue downstream that's creating excessive back-pressure.

Model: Alps Q-DL

Manufacturer's website: Q-DL | Alps Spas

Picture of spa innards:

https://imgur.com/YPKO5Gj

Video of leak:

 

[ajw22]

@RDspaguy may have ideas when he wanders by.

 

[RDspaguy]

That is the highest pressure in that pump system. It could be a blockage blowing the seals, but more likely it's just bad heater gaskets or loose unions. Do you have good flow at the jets?
The black pieces on the ends of the heater are threaded fittings and can loosen over time. Try tightening them up (hand tight) and if that doesn't do it replace the gaskets.

 

[krick]

Thanks. I was able to tighten the fittings a bit and it stopped the leak but I ordered new replacement gaskets just in case. The spa is about 8 years old. Not sure what the expected lifespan on those heater gaskets are.

 

[RDspaguy]

the expected lifespan on those heater gaskets are.

That depends heavily on your water chemistry, but I'd say you're above average there to get 8 years out of them. They can last many more, but few do.