Recently started brewing for a fairly young brewery. I don't know what the cleaning regimen for the heat-x was before I started, as the brewer was already gone, but I suspect it only saw chemical during BH CIPs and was probably just flushed w hot water pre/post brewing. It's possibly been clogged before, or at least had large amounts of material run through it (think NEIPAs). I've been giving it isolated caustic/acid fwd/rev, packing overnight, etc. The first few runs were shockingly soiled. Its gotten much better but still a decent amount of crap comes out.

So then our HLT goes down and creates havoc. Gave the heat-x a cool/warm caustic run but then it sat (unintentionally long) with only water in it for about a week while other fires were being put out. When we're back online I run hot h2O to flush in preparation for chemical and the water came out cloudy and smelled FOUL. Very much of sulphur mixed with gross. Gave it chemical every which way and once we get an extra set of plate gaskets it'll be getting opened up.

Anyone familiar with what could have caused this? No lab capabilities here yet but I intend to drop off a h2O sample at another local brewery that can plate it for us. I'll know for sure then, but because I'm impatient and in the event the chemical did its job and samples are clean I'd still like an idea of what we were/are dealing with.

On another note, I plan to start packing the heat-x packed with iodophor instead of caustic or PAA, as I've read this is more gentle on the gaskets. Anyone care to dispute, or is this generally considered best practice?