Chugger pumps losing prime

[bcrawfo2]

I've been using my chugger pumps for a few years on my 3 vessel eHerms and very happy with them. I always ran them wide open during brew day. In my HLT, I'd recirc. And from the MLT I'd pump thru a 50 foot 1/2 stainless coil. I took a few months off from brewing (busy with work) and built a new eHLT out of a keggle. When I did my water test and also my first brew day, I lost prime on both points at some time.

On my HLT, I have about 5 feet of silicone hose then then go thru a few fittings and then a 5/8 dip tube from Bobby. I choked back on the output of the pump and that seems to have calmed it down.

On the MLT...I can't get how I'm losing prime on him. I go thru 5 feet of silicone hose, a 50 foot coil, another few feet of hose, then into a Blichman sparge arm. Here the only thing I can think of is the arm is bouncing. But that's a lot of restriction. I even choked it back a little and I lost prime again.

Any ideas?

 

[RoadKing]

Air in the line is the usual suspect. But if If you don't think you're pulling air, maybe the impellers are gunked up a little from sitting. They're super easy to open up and clean.

 

[Drk93TT]

I installed a T and have a bleeder valve on the outlet.. the bleeder valve has a fitting on it that attach a hose onto- then into an empty milk jug which gets dumped out at the end of the day ... so it doesn't make a mess on the ground. No more loss of prime once I open it up before pumping lets the air out. If it starts to lose prime I open it again for a sec and its good. Just an idea for ya. Not "required" but I find it to be less annoying if it loses prime.

 

[mattd2]

I've been using my chugger pumps for a few years on my 3 vessel eHerms and very happy with them. I always ran them wide open during brew day. In my HLT, I'd recirc. And from the MLT I'd pump thru a 50 foot 1/2 stainless coil. I took a few months off from brewing (busy with work) and built a new eHLT out of a keggle. When I did my water test and also my first brew day, I lost prime on both points at some time.

On my HLT, I have about 5 feet of silicone hose then then go thru a few fittings and then a 5/8 dip tube from Bobby. I choked back on the output of the pump and that seems to have calmed it down.

On the MLT...I can't get how I'm losing prime on him. I go thru 5 feet of silicone hose, a 50 foot coil, another few feet of hose, then into a Blichman sparge arm. Here the only thing I can think of is the arm is bouncing. But that's a lot of restriction. I even choked it back a little and I lost prime again.

Any ideas?

HWats the intake side of the pumps set up like? From the fact that throttling back the outlet of the pumps solved the HLT issue I would think potentially you have a cavitation issue from a restricted inlet.