Hussman Protocol

[vacmaker]

I have a customer that is looking into using Hussmann Protocol self contained refrigerated cases for new installs. He has some concerns about the noise, humidity, power usage, maintenance and heat that they may generate with the evaporative element. If you have had experience with these units I would like to hear from you.
Thanks,
vacmaker

[bryan l]

I have worked with quite a few of them. Nice units if installed properly and you use the right controler. Noise is slight due to the insulated cabnet. There small so they dont take up much room. You cant get much more effecient due to the Scroll compressors they use. It all depends on the applications.

[icemeister]

I'm assuming you're referring to the Protocol LP deal where the compressor systems are mounted on top of the cases: http://www.hussmann.com/Products/images/pdf/LPproto.pdf, not exactly self-contained in my book.

I've never seen any of these yet, but the heat can't be much of a factor and the noise shouldn't be a problem if they play the Muzak loud enough.

One thing I know for sure is that I wouldn't volunteer to service one.

[condenseddave]

Originally posted by icemeister
One thing I know for sure is that I wouldn't volunteer to service one.

Good plan.

Don't raise your hand for a Protoair, either.

[thegoodhumorman]

I recently got to see one of these bad boys- however the condensing unit was remoted to the receiving area of the store and handles both med and low temp cases on sales floor -common liquid line.
I thought the unit was pretty quiet- panels are indeed insulated. Main breaker is accessible on top of unit ok, but my misfortune there was no schematic anywhere.
From a class I had taken a few years ago these beasties
were slotted to be fluid cooled with plumbing from a main tower looped thoughout the store. Thankfully that was not this particular unit, but that is an available option.
The footprint was of reasonable size, but I havent had to weld inside the housing yet- my opinion could change as fast as the size of eyebrows burning.
I do think that you could like them- the controller would definitely be key- this unit had a 4K which was clashing with a pressure switch that was hidden up in the rear (thanks @%#$@#^ hussmann)-schematic on hand now!
All in all not too bad, but now those units attached to a case on the floor...couldnt say.

[condenseddave]

You start working inside of one, your humor won't be so good.

[K_Neil]

Just started service work on a (approx.) 8 yr. old Hussman Protocol today for the first time. It runs 2 30 ft. cooler displays & 2 cooler walk ins. 4 compressors. 1 display was froze up #1 compressor was an ice block #2 compressor was 1/2 an ice block. Unit alarm light was on. Store owner was watching pretty close and asking a 1000 questions that I couldn't find the answer to untill he gave me some room. U guys bin there dun that. there's a hand held programmer that the owner had hooked up before I could even blink. I have some homework to do and have to figger out the quickest way. Got lucky today and hit the rite buttons. Actually programming everything hasn't ever bin finished by my quick look. The service tech that looked after it before is no longer easily available so I'm under some pressure to figger it all out. Any hints on programming would sure be appreciated. The manuals are there but actual logic sometimes isn't.

[man from trane]

Just started service work on a (approx.) 8 yr. old Hussman Protocol today for the first time. It runs 2 30 ft. cooler displays & 2 cooler walk ins. 4 compressors. 1 display was froze up #1 compressor was an ice block #2 compressor was 1/2 an ice block. Unit alarm light was on. Store owner was watching pretty close and asking a 1000 questions that I couldn't find the answer to untill he gave me some room. U guys bin there dun that. there's a hand held programmer that the owner had hooked up before I could even blink. I have some homework to do and have to figger out the quickest way. Got lucky today and hit the rite buttons. Actually programming everything hasn't ever bin finished by my quick look. The service tech that looked after it before is no longer easily available so I'm under some pressure to figger it all out. Any hints on programming would sure be appreciated. The manuals are there but actual logic sometimes isn't.

I was there a few weeks ago (learning Protocol, not that store ) If yours has CPC and your compressors are short cycling the first thing you will want to do is get the TR (throttling range) above the factory default of 30. I had to go to 60 with an integral of 1.5 to get it steady. (less "P", more "I", no "D") These units are shipped with the minimum programming to get it running and then a tech like yourself is supposed to go in and finish up. Mine short cycled and tore up 3 compressors in 2 years and ran with other problems because no one ever commissioned it.

They're a great system as far as I'm concerned. I'm going to change out some comps on another one in a couple weeks. I hope the new ones have Rotolocks!

[MikeySq]

I hope the new ones have Rotolocks!

do you mean there's protocols with braze in compressors? that's dumb

Got one out there now with 2 suction groups, the #1 comp on the MT side is way too much for low load situation and bangs on and off like crazy, It runs all the time now so the problem is not really fixed, but the suction pressure is a bit lower than it's design

Mike

[man from trane]

do you mean there's protocols with braze in compressors? that's dumb

Got one out there now with 2 suction groups, the #1 comp on the MT side is way too much for low load situation and bangs on and off like crazy, It runs all the time now so the problem is not really fixed, but the suction pressure is a bit lower than it's design

Mike

I should have clarified...the customer ordered the compressors. I hope they ordered them with Rotolocks.

[Dowadudda]

I also like protocols. I think it's a neat idea and the ones I have worked on, have given me little trouble. I mean they break like anything else. Add you fix it and your on down the road.

I'd like to see more of these out there in smaller stores. C Stores, restaurants.

[MikeySq]

I should have clarified...the customer ordered the compressors. I hope they ordered them with Rotolocks.

i'd be surprised if you could order them without, that would be just weird!

[man from trane]

i'd be surprised if you could order them without, that would be just weird!

For some reason you can. It only saves about 40 bucks, which in my opinion is nothing compared to the trouble of buying them separately and brazing them in!

[MikeySq]

so what do they use ball valves for isolation?

[man from trane]

so what do they use ball valves for isolation?

The only one I've worked on had standard service valves at each compressor.

[MikeySq]

I'm confused now... haha I've only seen scroll compressors with braze ends with no valves or with roto-lock connected service valves. Just curious what would those standard valves be like??

[rosspoling]

I have been using this system for a while. If the system is installed correctly the system will save money over normal system, it uses less freon than most units. It cost less to operate. We use them in Aldi and they love the systems

[thefreezerguy]

do you mean there's protocols with braze in compressors? that's dumb

Got one out there now with 2 suction groups, the #1 comp on the MT side is way too much for low load situation and bangs on and off like crazy, It runs all the time now so the problem is not really fixed, but the suction pressure is a bit lower than it's design

Mike

I have many of these with the same low load issue. Would you elaborate on what you have done to shorten the cycles and smooth out the suction? I would appriciate any successes that any of you have had on this issue.

We have a lot of customers installing protocols with the fixtures all being controlled by suction stop. The load varies greatly all the time and the suction and compressor cycles are all over the road. I have been raising the suction target and insuring that all the fixtures are set at spec for longer system run times and to reduce the suction stop cycles. I have also been playing with the suction setpoint differential, etc (Enhanced suction).
Some success but still looking for input from anyone.

I also have many that are using Comtrol. This is proving to be even more of a challenge as the 4k/4k2 is not as flexible as the E2

I thought if installing a digital scroll but the customer is opposed to using them..... UGH!

[man from trane]

^ The 4K is now obsolete. Maybe a good time to upgrade to E2. As far as improving control, it's best to have a good range of sizes, such as a small 5 HP compressor, a 10, and several larger ones so that there can always be a combination of pumps running that come close to matching your load. I also find it helpful to stagger defrosts so that you don't have a bunch of cases with no load all at the same time.

Finally, you might consider using SORIT valves instead of suction stops. That way the case is always "on" except in defrost. It evens out the load considerably. I've also had issues with floodback after defrost with the suction stops. Not sure why.

[thefreezerguy]

^ The 4K is now obsolete. Maybe a good time to upgrade to E2. As far as improving control, it's best to have a good range of sizes, such as a small 5 HP compressor, a 10, and several larger ones so that there can always be a combination of pumps running that come close to matching your load. I also find it helpful to stagger defrosts so that you don't have a bunch of cases with no load all at the same time.

Finally, you might consider using SORIT valves instead of suction stops. That way the case is always "on" except in defrost. It evens out the load considerably. I've also had issues with floodback after defrost with the suction stops. Not sure why.

Thanks for the comment!

Our customer that uses Comtrol has chosen to use Danfoss when an overlay is needed. I was hoping they would choose E2.

However, another one of our customers using protocol is using E2. But all systems are suction stop like I mentioned. This comes down from corporate engineering. Nothing I can do about that, they will not allow us to go in and use SORIT. I agree with you, that would make a big difference. To this customer, if it won't save energy, and a lot of it, they won't do it. They use this logic on being resistant to digital scroll.

As far as compressor sizes, I am lucky if the lead compressor is smaller. Most times they are all the same.

With all that, I am having to try to come to a adequate solution with what the customer has given me to work with. Double