MarshMan
25-06-2009, 04:51 AM
Hello I need help with an A/C on my friend's boat. He just got it and called me to come service it. I have never seen such a unit as this before and without a charging chart or any dataplate information is gone. Searches for the name on the unit it "Air De Mer" comes up with nothing. The unit can best be described as a "heat pump chiller". The pressures stamped on the LP control are 50psiCO/75CI. It is a cap tube unit. Two heat exchangers are seperated and one runs seawater through it and the other runs a water loop connected to 4 remote air blowers each with a high and low fan speed switch. Basically I want to know how to determine if the unit is charged correctly without a charge label.
I currently have a 50/50 mix of ethylene glycol antifreeze in the loop. I vacuumed it down and weighed in 24 ozs R22 to bring static charge up to about 125. Started up and got 240psi/70low. Seawater was 90F. Cabins were at 92F with RH of near 75%. After running an hour with fans blowing on high pressures went down to 235/67. Temps dropped to 89F and RH to 67%. Discharge air was 78. I adjusted charge up and down a few ounces and still only could get 12F split and even with the fan speeds set a low didn't help.
Is this all I can expect ffrom this unit or could I not be charging it right? Compressor is running cool, and doesn't appear to be slugging so we are leaving it run all night with fans on high and see what happens.
Can anybody help me?
I currently have a 50/50 mix of ethylene glycol antifreeze in the loop. I vacuumed it down and weighed in 24 ozs R22 to bring static charge up to about 125. Started up and got 240psi/70low. Seawater was 90F. Cabins were at 92F with RH of near 75%. After running an hour with fans blowing on high pressures went down to 235/67. Temps dropped to 89F and RH to 67%. Discharge air was 78. I adjusted charge up and down a few ounces and still only could get 12F split and even with the fan speeds set a low didn't help.
Is this all I can expect ffrom this unit or could I not be charging it right? Compressor is running cool, and doesn't appear to be slugging so we are leaving it run all night with fans on high and see what happens.
Can anybody help me?