Hussman rack question

[rlbhvac]

Yesterday get a call from a market i just started serviceing,"i think my rack is low on gas".
Now i will admit this is the only market that i service that has a rack,and i don't get to work on any because of that.He bought it used and had it installed by his old service company.
The rack is a Hussman super plus,asked him why he thoght it was low when all the cases it runs are fine.On the reciever tanks on the bottom of the rack is a large gage,that says hussman liquid leval,percent of pump
down capacity,its reading 10,says he was told it should always be between
20 and 25.Is that right?
Now if needed how and where do you add gas to thies things,
Theres more shrader ports then i've ever seen on a system.He said
the old company would shut it down wait a hour then add gas on
the line marked return from condenser,which goes to the reciever tanks.
This is my first and only rack i have in my service area so any help
is a help.
its a Hussman super plus,useing r22,running about 100 ft. of combined cases.
Thanks,
Randy

[crackertech]

10% is ok if thats as low as it get's does the rack have heat reclaim on
it if so was it running at the time.I think 10% is fine with heat reclaim running.
as far as adding gas add it at the line up there should be a suction schaidr
by the txv hook up and let go.dont forgrt dump it in liquid not vap.

[engineerdave]

Back away slowly, don't touch anything. Call your boss and ask for onsite guidance.

Before you start adding gas, verify a leak actually exists. Then fix it.

Keep in mind that there can be any number of scenarios that may caus your reciever level to dip, including a faulty Level Indicator.

Some things to look for:
1) Stacking in Condenser
2) Insufficient Airflow / Heat Exchange in one or more Systems
3) One or more Systems in Gas Defrost

Be thorough. Good luck man.

[mccool]

Like Dave said....if you don't know where to add gas, back away. Ask and learn onsite, 10% is too low, if it has a low liquid alarm that is the % that it will start timing out and go into alarm unless it rises above 15% before it times out. You need to know what are normal settings for hold back and bypass valves + condenser fan settings to determine if this is affecting the level.
Hopefully the service log book contains a history of past receiver levels at certain ambient temps./conditions, previous gas added etc., check it for comparision. If the customer is well educated about his system than he could be correct and there is likely a leak somewhere

[rlbhvac]

Ok Mcool and Dave first let me state,i am the office and the boss and the service guy,i'm a one man show,independent,what ever,but i don't want to hack something thats why i'm asking here.
Next i did find and fix several leaks most in the original installing
companys work.When i first went into the rack room i could'nt even get close
to the the door with out my leak detector going off,had to leave the room,
even in the batroom next to it was going off.
This guy is a small market guy with 3 stores and the big sevice companys in our area,basicly screwed him(one company charged him for two guys that were'nt even on the job).And as far as alarms and such on the rack,nill,all disconnected along with the heat circut,so thats why i'm asking for help.
Thanks in advance,
Randy

[mccool]

Sorry but the kind of info you seek cannot be dispensed over the web like so many pez. For reasons of safety, job security etc. Word of warning though, new customer, small player in the markets, C.O.D.

[dirtyboy103us]

charging a rack is easy just dump in a case that has a service port in it start with a 30 lb and see where it goes 25% is the normal range with all systems calling but it will go up and down depending on the type of defrost you have

super plus with what kind of defrost and length of runs would help and do they pump down on liquid valves at the rack or cool gas defrost these are important to know and get used to.... 10% is not low just not the recommended level for proper defrost if it is cool gas as it may bottom out during defrost of a large system and starve the last systems during defrost also with time off defrost where it shuts down the sorit where it will fill the system with liquid starving another system or two

if you do charge at the rack the pumps don't like liquid as like any other if they have accumulators they will help

this is refrigeration and just take it slow and you get to know this side very quickly its just one circuit at a time and is it a rack problem or a case problem
and its that simple just has to broken into pieces


call is= all systems running warm = sounds like a rack problem
call is= system 3 running warm = case or circuit problem

easy

keep freon in rack(leak checks) and changed driers yearly and keep oil clean
very few issues

[dirtyboy103us]

another thing as you get used to the way it runs you will find the secrete decoder ring in the cabinet some where

[dirtyboy103us]

take some pics and post of this thing and of valves you don't know and some one here can tell you or lead you to some reading material that will give a head start on issues that will arise and you can figure it out right now

there is no worse feeling in a quiet motor room at 2:00 am with nobody to call

email me dirtyboy103us at yahoo dot com and i'll give you my cell # or nextell #


Good luck

[jappell]

Now that would be cool, a pez dispenser holding a set of gauges

[rlbhvac]

Dirtyboy just wanted to say thanks.I got it figured out and ended up putting 120 LBs in it,and yes i'm still repairing leaks.Found lots of stupid little ones and one large one in the condenser manifold,think i'll be going back on this one a few times to get them all.
Randy

[markettech]

Dirtyboy just wanted to say thanks.I got it figured out and ended up putting 120 LBs in it,and yes i'm still repairing leaks.Found lots of stupid little ones and one large one in the condenser manifold,think i'll be going back on this one a few times to get them all.
Randy

Cha............................................... ...........................Ching

[dirtyboy103us]

Cha............................................... ...........................Ching

yes sir keeping that gas in the rack will be boring after a while but, just leak checking and repairing 10 small add up to a blower every month

and being in the motor room for hours you get used to the humm and can here something going down

did you find that RING