Replynot sure on scotsman but most of the time when IM manufacturers list operating pressures it is 5-10 minutes into freeze cycle.
Professional Member
According to the maunal on my Scotsman 1356 the discharge pressure should be 245. Now is that all the time or when it going through a freeze or a harvest cycle? I've been trying to adjust it but it keeps kicking out on high pressure overload.
Professional Member*
not sure on scotsman but most of the time when IM manufacturers list operating pressures it is 5-10 minutes into freeze cycle.
Professional Member
water cooled or air cooled , Man i remember a couple years ago Scotsman had issues with the dist. tubes coming off TXV , causing uneven ice forms and high head , if its a remote ,
check your gas level a lot of guys don't realize that those units are charged at factory they install and start dumping 404a into line sets , as far as pressure with fan cycling or water reg valve
you should have operating temp fairly quick
Ice V
Outlaw guns? only outlaws will have guns
Those who live by the sword are SHOT by us who don't.
Professional Member
Ice,
Sorry it is water cooled. That's what I'm talking about is the regulator that adjusts the water pressure going through the condenser. The amount of water flow adjusts the head pressure. I need to adjust it so its at 245 but not sure at what point in the procedure it needs to run at 245. Hope I'm making since.
SDC/Educational/Membership Committee*
Water-cooled machines will typically run at the same discharge pressure all the time because the water regulating valve controls the pressure. If the supply water temperature is too high or the available pressure is too low, then of course, even a wide open regulating valve won't help.
To set the pressure at 245 psig, I recommend adjusting to a slightly higher pressure like 260 psig or so, and then slowly dial down to 245 psig.
Also...It's a good idea to do this about 5 minutes into the freeze cycle.
Professional Member*
What is the discharge pressure doing? Steady? Steady climb? Hunting up and down? What pressure is it tripping at? Back valve way off before you start the machine and evaluate. Is water coming out hot, warm, or cool? Need to gather some more info to lead us to the actual problem.
Professional Member
245# is the setting for freeze cycle
Professional Member
It wasn't harvesting. It wasn't getting a high enough head pressure when the hot gas valve opened, hence not hot enough gas, to break the ice off the evaporator. I was trying to set the water pressure regulator but I don't think my charge is right to get it where I need it. Let's just say there's been a lot of hands in this machine before they came to me. We have a lot of guys here that have the attitude if its not running right I must need a shot of freon!!
Professional Member*
Confused now. Tripping on high head but not high enough head to harvest?
Professional Member*
What pressure is it cutting out at.
Sent from my SGH-T999 using Tapatalk 2
Professional Member
When I wasn't high enough I was trying to set it and no matter where I set it it was tripping out. That's why I was asking at what point in the sequence I needed to set it. Also that's why I'm thinking my charge may be off. Hope I'm making sense here.
Professional Member*
How long into the cycle did it trip? Did you check amps?.. are you sure its tripping on high head. Usually you will see on most units that high head will cut off at around 300 or above.. so definitely double check what your tripping on and at what pressure...
Sent from my SGH-T999 using Tapatalk 2
Professional Member*
Don't know if charge is the issue or not. Easy to know for sure. Pull it. Weigh it and see. Evacuate and weigh correct charge in. I would do alittle more checking first though. Find out what it actually tripping and why. Is it HP or comp internal OL? Still alittle confused with the info provided.
Professional Member*
could be non condensible or mixed refrigerants???
Professional Member
I`ll second that.Originally Posted by beb
Professional Member
On water cooled machines, the first thing I look at when they don't harvest is the water regulating valve. Often especially in hard water areas, the valve seat will clog with minerals and not seat all the way. It is essential that water flow stop during harvest to allow heating of gas. A sure fire way of testing is to valve off water flow to condenser during harvest. If it drops valved off but doesn't when valve is open, you need a new water regulating valve.
Professional Member
Another question on this issue. If the valve is bad, is there a way I can isolate the refrigerant in the system so I can change it without evacuating the whole system?
Professional Member
You can change the water discharge valve without recovering the refrigerant. I feel as I should mention, however, that if you suspect that the system is overcharged, you need to ensure that you have a correct charge. Then you adjust the water discharge valve. If you ensure that you have proper charge and correct water out pressure and continue to have the unit tripping on high discharge pressure, your next step is to clean the scale off the water side of the condensor.
Professional Member
The pressure regulator is bad. Doesn't matter how you adjust it it is wide open. So I need to replace it and don't want to evacuate it.
Professional Member
You should be able to secure the water and replace the valve.
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