Strange problem with air in pump

[Smellyglove]

A few years ago I had a problem with my March sucking air into pump. I figured that out as it was air bubbles forming and getting trapped beneath the FB and getting sucked into the pump as the HERMS heated the water.

Since then I've put together a new system which has been running flawlessly since last august.

Now I haven't been brewing on it for the last two or three weeks, and I'm all of a sudden getting air.

If I run MT - pump - MT, it works nicely, if I run MT - pump - HERMS - MT, I'm getting air. Everything has gotten new teflon tape, and I've swapped hoses around, opened up the pump, but it happens after ten seconds when running through the HERMS, I can run without the HERMS with no problems. I can't see a single bubble of air in the MT. The HERMS-loop adds some restriction. FB is not installed when this happens.

Anyone know what might be going on here? It's just cold water. I haven't touched a thing, it just magically started to happen.

 

[day_trippr]

Do you have disconnects like camlocks in the path leading to the pump inlet port?

Cheers!

 

[Smellyglove]

Do you have disconnects like camlocks in the path leading to the pump inlet port?

Cheers!

Yes, I've swapped one of them for a backup I have. But I' did also swap the hose for a different one with QD's. I've been testing more, and MT - Pump - MT also gives me air, but at a way lesser extent. So I think that with the HERMS the problem is just manifesting itself faster than without the HERMS.

I'm getting some really bad flashback to the problem I had a few years ago, It's demoralizing me to the point where I just wanna take some karate-classes just so I can kick the crap out of that POS airleak, pump, hoses, and everything else.

 

[Smellyglove]

Oh well. Before I left my basement last night I set the PID to 80C, and shut it down one hour later on a timer. I thought maybe if I heat that thing up again.. Well, today it works like a charm. Weird. The brewery has not been used for three weeks, I guess it tried to punish me for that.

 

[IslandLizard]

Do you have disconnects like camlocks in the path leading to the pump inlet port?

Cheers!

What's wrong with camlocks there?

 

[day_trippr]

Nothing, unless they don't actually mate without leaking, like when the o-ring is damaged, missing, or under-size. Some folks have also had leaks when mixing parts from different manufacturers.
I have a crap ton of camlocks on my 3v dual pumped herms rig with no sucking air leaks but it's bitten a couple of folks in the past...

Cheers!