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cesarsavinon
08-21-2004, 09:47 AM
Anyone familiar with Lennox RTM (Refrigerant tank module)I have one installed with one single speed 5 ton condensing unit and 4 wall ductless units 5 tons total. The problem is with the pressures. Suction is 65 psi, liquid 125psi too low, Change the dessuperheater valve and have no change, considering to change the suction regulator, but would like to have some help from any body familiar with this type of unit.

madarius
08-21-2004, 11:35 AM
your discharge flapper reed valve may be defective causing low pressure on the high side. The effect of a defective flapper reed valve causes the gas in the cylinder to open the reed valve, prematurely, before the piston hits top dead center. The reason for my theory, by what you told me, is that 65psi is normal on the lo side. If there were a restriction with the automatic/ TXV valve then your discharge pressure would be high given the fact that the condenser is holding back refrigerant due to the restiction of the Xpansion device, thus making your lo side pressure abnormally low. Do not attemt to recalibrate that TXV because, 1) that is notthe problem 2) it takes at least 24 hours to get the result of your calibration 3) adjusting spring tension re-adjust the way the valve is supposed tp respond to a 10 degree superheat.

If there were a restriction in your evaporator, then that would be conducive to an abnormal lo side pressure. All of the gas in the cylinder space, of the reciprocating compressor, probably is not being used for compression.

[Edited by madarius on 08-21-2004 at 11:52 AM]

cesarsavinon
08-22-2004, 10:30 AM
Thanks for your response madarius, I will check the compressor when I get back there and let you know. Thaks Again.