failure after power steering rack replacement

Hi. I have a 1998 NB TDI with 235K miles that has a power steering rack failure. I replaced the old one that had been leaking through the seal and into the boot on the passenger side. I removed the old one and put in a new one. I put in fluid and turned the wheel from side to side and got a bunch of foam in the reservoir that eventually subsided...I kind of expected that anyway since any air in the system during bleeding is going to come out through the low pressure side into the reservoir.
Anyway, it was good for a week and the new rack failed. I pulled the new one out and I see that the seals on the drivers side failed and fluid is coming through the boot on that side.
Any suggestions on this? I suppose the new part I put in could have been defective, but I am not sure. I intend to put in another one, but I would rather know root cause on this one since I am getting tired (and quite good at) changing the steering rack on this car! I will inspect the fluid for metal/debris/etc, but I didn't see anything in the stuff that dripped into the pan I have under the car.
Anyone know where the pressure relief valve in the system is? On the pump?

Where did you get the steering rack? New or refurbished?
I don't thing there's a pressure regulator in that system. The only time pressure should effect it negatively is if you turn to the stop. Then if you force it to far, or keep it there, it'll cause damage.
Likely a faulty part, especially if purchased from aftermarket and box stores.

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Got the rack from idparts.

Did you check the pump for wear? If it was low on fluid for some time it will show it when you take it apart.
Did you flush the piping out before installing the new rack?

System was flushed. Probably used 2l of fluid for that.
Did not inspect the pump. I suspect the car was driven maybe 10 miles when it had problem the first time. I don’t know for sure as my daughter drives it.

Not sure how good this aftermarket part is from idparts
It’s an “Atlantic Automotive Engineering part”.
I assume it’s goodand maybe the pump is hosed....debris/chips/hazy in the system might show up in the fluid, but I don’t see that.

It's not difficult to repair the old rack unless massive savings gacked up the works.
I would tear down the old oem one and find out if it's just as simple as some seals and o'rings.

I've seen an online video of a rack rebuild (seal replacement) - it might be something I could tackle. Although this one has 235K miles on it and it is a little rusty at the bushing/mount end of the rack so not sure if it is worth it.
Where is the best place to get a seal kit?

Another somewhat related question-
I have a Panzer skidplate installed on the same NB. After removing it and dropping the subframe to remove the steering rack, I wondered about the structural aspect of the subframe that the skid plate 'modifies'.
The skid plate bolts to the subframe and to the body of the car (through standoffs). The subframe has bushings which seems to indicate that there is some movement in the subframe. Considering the skidplate connection to the subframe, wouldn't the thick (non-compliant) skidplate provide an additional 'restriction' on the subframe? Is that an issue?
Sorry for the dumb question - I am not a mechanical engineer!

The subframe is firmly attached by the front bolts...no bushings on that end. The rears have bushings as you say but is more for vibration damping or maybe thermal expansion of the chassis. They are pretty firm bushings. It does not appear to be an issue about the skid plate. If anything it adds stiffness to the front end and how could that be bad?

Thanks JETahh. I wasn't sure about the skidplate - it was just an observation when I was dropping the subframe and the fact that the factory skidpanel is certainly compliant. The subframe bushings will get less wear and tear with the skidplate installed.
Back to the power steering issue. It may be that the power steering pump pressure regulator has failed (although a failure to high pressure is a lousy failure mode!). Hydraulic pumps should have a regulator in them in order to limit the pressure over the operating range of rpms. The pressure regulation must be internal to the pump, but I have not seen any pump dissections online. Maybe this is only a failure mode with high mileage pumps?

so....to conclude this thread, the fix to this issue was a new steering rack as the new one from IDparts was defective. Put in replacement rack and after tearing down the pump to confirm that the pump was not the point of failure, I put another pump in that I had from my old 2000 jetta. Everything works like a charm now!

Rebuilding rack youtubes lack critical info.