MR Series Heatless Mini Regenerative Desiccant Dryer. Operator s Manual

MR Series Heatless Mini Regenerative Desiccant Dryer Operator s Manual

Introduction Many years of trouble-free service can be expected from your Numatics regenerative dryer. Superior dew point depression will be obtained and operating problems will be avoided with careful installation and proper preventative maintenance procedures. Location The ambient temperature of the dryer should fall in the35ºf-120ºf range. The dryer will function in warmer surroundings, but the degree of dew point depression obtained will decrease. All Ultra Air dryers are designed for indoor use only. Dryers located outdoors require a Low-Ambient Package. A protective roof is absolutely needed so that the dryer will not be directly exposed to rain and snow. Before using the dryer, make sure that no pipe or tubing connections have become loosened in transit. Make the necessary control power electrical connections and make sure the dryer is grounded. Recommended Installation Making the following connections: Inlet piping (including a shut-off valve) Outlet piping (including a shut-off valve) Prefilter(s) and afterfilter(s) Bypass piping (if desired. Use a bubble-tight valve for bypass) Electrical connection to control box An access connection should be made upstream and downstream of the dryer for dew point and temperature checks Required Pre-Filtration All regenerative desiccant dryers are designed to remove only water vapor. The possibility of liquid water carryover to the desiccant dryer must be avoided. A coalescing prefilter will eliminate the carryover of droplets and aerosol-sized mists of both liquid water and compressor lubricant. Required After-Filtration All regenerative desiccant dryers gradually produce hard and abrasive desiccant fines. These contaminant should be removed with and Ultra Air particulate afterfilter to keep downstream air from clogging the air lines. Optional Block and Bypass Suitable manual block and bypass valves should be installed to facilitate servicing of the dryer and filter without interruption of compressed air flow. Valves must be bubble-tight to prevent water vapor migration around the system from the region of high relative humidity to low relative humidity. For a typical installation, block and bypass valves should be installed around the entire dehydration system prefilter, dryer, and afterfilter. 1 MINIATURE REGENERATIVE DRYER INSTRUCTION MANUAL

Desiccant Fill and Drain Ports The MR-10 and MR-15 model towers are filled with desiccant by Numatics at the factory. The desiccant can be replaced by unbolting the top plate. The average life of the desiccant is two to three years depending on the working condition of the dryer and the maintenance of the filters. If the color of the desiccant has changed from the original white to pink or yellow, it is fully saturated and cannot be regenerated. Operation The operation of the MR dryer can be readily traced by referring to the enclosed flow schematic drawing. The operating sequence is fully automatic and is controlled by an electronic solid state timer. Wet and dirty compressed air leaving the compressor aftercooler and mechanical separator is freed of all entrained liquids and aerosols, as well as solid contamination, by the prefilter. Separated liquid contaminant is discharged from the prefilter sump through the automatic drain valve. Wet air enters the inlet 4-way valve (1) passing through the strainer, the strainer (2), the desiccant chamber (3), and through the outer check valve (4). Then the dry air exits through the dryer outlet. A small portion of the dry compressed air is expanded to near-atmospheric pressure by passing through the purge orifice (5). Expansion of this already-dry gas to near-atmospheric pressure increases the ability of the purge air to strip the previously absorbed water vapor from the partially saturated desiccant bed in the right chamber. The water vapor removed from the right chamber desiccant is passed to ambient through the 4-way valve (1) and exhaust muffler (6). Before tower switch-over, the 4-way valve (1) stop the air from purging. At that point, both towers (online and offline) are up to line pressure and ready to switch, assuming that both towers will be at equal pressure and no desiccant bed bumping will occur during switch over. The dryer 4-way inlet valve (1) switch then diverts the inlet compressed air to the right tower and the purge air escapes through the left tower. This process repeats as long as power is on. Should power to the dryer be lost or turned off, the sequence of operation will not be disturbed and will remain as is, also, air will still flow through the 4-way inlet valve (1) and out through the dryer outlet. The cycle is as follows: 1) the online tower dries for 30 seconds 2) the offline tower regenerates for 25 seconds 3) the offline tower repressurizes for 5 seconds. The entire cycle takes 60 seconds to complete for a -40º dewpoint system. MR-10/MR-15 Flow Diagram MINIATURE REGENERATIVE DRYER INSTRUCTION MANUAL 2

Start Up A) Verify that the air inlet and air outlet are connected properly. B) Verify that there is a high quality oil-removing prefilter installed upstream of the dryer C) Verify that there is a high quality drain system installed on the prefilter to assure the filter is properly drained. D) Verify that the proper electrical connections are made to the dryer. Check the voltage on the data label of the dryer. Check the line voltage and amperage of the electrical line connected to the dryer. Make sure the line voltage and the data label voltage are the same. E) The dryer upstream and downstream isolation valves should be closed and the bypass valve should be open. Before turning on power to the MR Series dryer, slowly pressurize the dryer by gradually opening the isolation valve upstream of the dryer. When both tower pressure gauges indicate line pressure, the dryer system outlet isolation valve can be opened and the dryer system bypass valve closed. Compressed air then flows through the prefilter, MR Series dryer, and afterfilter. Dryer operation should never be initiated by sudden pressurization of the dryer towers from the dryer inlet. The sudden rush of incoming high velocity air into the desiccant bed could cause damage to the prefilter and afterfilter elements. Power to the MR Series dryer should, at that point, be turned on. Immediately after activating the dryer control circuit, one tower will depressurize to atmospheric pressure through the purge exhaust valve. Regenerating purge air will then flow to the offline tower. Maintenance A) Prefilter The prefilter element must be replaced whenever the pressure drop over the filter exceeds 5 PSID or the indicator in the gauge points to the change zone. It is important to check the operation of the automatic drain trap or valve at frequent intervals to ensure that no liquid carryover into the dryer occurs. Ultra Air recommends prefilter elements be changed every 3 months to ensure proper filtration. This will prolong desiccant bed life and ensure clean, dry air downstream. B) Afterfilter The filter element must be replaced whenever the pressure drop exceeds 5 PSID or the indicator in the gauge points to the change zone. Whenever changing the prefilter, the afterfilter should be changed as well. C) Desiccant replacement For best results, change desiccant periodically. Be sure to use only Numatics Activated Alumina which can be obtained through your Numatics or Ultra Air representative. Numatics Activated Alumina excels in dew point depression capability and attrition resistance. WARNING! Failure to maintain and change prefilter on a regular basis could damage desiccant bed, cause dryer failure, and void any and all warranties! 3 MINIATURE REGENERATIVE DRYER INSTRUCTION MANUAL

Troubleshooting Problem Possible cause Solution Poor dew point Excessive inlet flow Reduce flow to rated capacity Check upstream separator, prefilter, Excessive inlet temp (above 120ºF) Excessive water Desiccant fouled by lubricant Prefilter drain failure Low inlet pressure Contaminated Check upstream aftercooler and drain traps Replace desiccant and prefilter element Check for clogging. Clean, repair, and/or replace Check for pressure loss over prefilter. Check dryer sizing based on flow and temperature Change desiccant Excessive pressure Excessive inlet flow Reduce flow to rated capacity or drop install larger dryer Low inlet pressure Excessive pressure drop over prefilter and/or afterfilter Saturated desiccant Check for pressure loss over prefilter Change filter elements Change filter elements MINIATURE REGENERATIVE DRYER INSTRUCTION MANUAL 4

Standard MR10/MR-15 Parts Diagram Standard MR10 Dimensions & Components Legend: A Air outlet B Air inlet C Electrical access box D 4-way valve E Desiccant tower F Pressure gauge G Muffler Standard MR15 Dimensions & Components Legend: A Air outlet B Air inlet C Electrical access box D 4-way valve E Desiccant tower F Pressure gauge G Muffler 5 MINIATURE REGENERATIVE DRYER INSTRUCTION MANUAL

MR10/MR-15 with Optional Mini-Pak Legend: A Air outlet B Air inlet C Electrical access box D 4-way valve E Desiccant tower F Pressure gauge G Muffler H Diff. pressure gauge I Coalescing filter J Adsorbing filter K Particulate filter L Drain Solenoid Drain Valve Replacement and Repair Kits Model Description LFT25 VAL-SO-04-59-4W ELE-TB-59-CR MUF-PU-5-SH Purge muffler (2) GAG-214-103 Pressure gauge (2) VAL-CK-4-PK Check valve (2) Inlet valve (4-way double solenoid) Timer board FIL-TF-4 Tank strainer (2) DES-AA-2-00 Desiccant (10 lbs/.31 kg) MINIATURE REGENERATIVE DRYER INSTRUCTION MANUAL 6