Pond Boss Forums Thread Like Summary - Kasco RA2 prv issues

So I’ve been in constant contact with American aeraton and a Kasco rep on trying to solve my issue, but I wanted to ask the forum if they had any ideas on why this is happening and if anyone has had this issue before. Btw, both guys that have been helping me on this are absolutely fantastic and super helpful. Probably the best customer service I’ve had on anything I’ve ever bought. Matt from American aeration is actually sending me a new unit to see if thats actually the issue here..

Anyways, my set up.. I have a Kasco Ra2 unit with 2 diffusers. One at 3’ with a full length of provided weighted hose and a diffuser at 8-9’ with about half the length of provided hose. I turned the deep end off for the winter and letting the shallow run solo. I’ll let it run and the unit within 30 mins to an hour maybe even a few hours (it’s very random) starts setting off the pressure relief valve and it’ll start “burping”.

I’ve entirely disconnected the diffuser on the shallow end so no obstruction (besides maybe chance of something being in the line itself)(hopefully not) and I’ve played around with switching the valves, opening and closing the deep end and shallow while the burping was present. While burping with the shallow end open, I would close it and open the deep end. The burping would stop. I’d close deep end and open the shallow and the burping would persist. Which makes me think there is a blockage in the shallow, but why would it run fine for hours, no problem at all? The flow out of the line is pretty intense and doesn’t look light.

I’ve questioned having a bad prv spring and maybe it’s light? Idk. I’m trying to do anything besides unbury my lines. Also from the unit itself to the pond I have both lines insulated to the ground (~3.5’) that run to a pvc pipe that runs about 10’ to fully buried line that spans maybe 6-7’ if that.. before entering the pond. I’ve also been pretty careful with “crushing” the line when I put it in but who knows.

If the line is somehow crushed or if there’s a blockage, is there something I can run down it to possibly free it? Speaking of running stuff down the line.. I’ve poured iso alcohol down the line which would “fix” it for a few hours before it started up again.

Sorry for such a long text

^^DrewSH is correct. I'm going to take a SWAG and say that your buried line is 3/8" ID? Correct or incorrect?

If so, and the other line is the same ID I'd bet that there is a rise/dip in the line that is letting condensate collect and most likely freeze in the line.

How long is the run underground to each of the diffusers? When it burps, what is the pressure that is in the system? If you don't know what the pressure is, add a low pressure gauge (0-30 psi)

If the line is freezing you have 2 options.

1) run another line but make it 1" ID. You can neck it up/down where it enters the pond and where it exits the compressor. You could go 1/2", but the cost difference is minimal and it takes the same amount of labor to go with either size. You use black low pressure poly tubing for the run. We've run 1" line over 900 feet to a pond without any freezing issues, and we only ran it 12" deep. I know there are rises and dips in the line but it hasn't been affected in the 5 or 6 years that it's been there. That 1" line replaced a 3/8" line that was constantly giving the pond owner problems in the winter.

2) You buy one of these and install it near the compressor. It automatically injects alcohol in the line when back pressure reaches a certain psi. air line de-icer 1 air-line deicer 2