User manual DOMETIC L-2175

[. . . ] EPROM chip replacement On multiple chiller units systems with more than one chiller boards networked together, if an EPROM chip is being replaced on any chiller boards, you will need to initialize the boards again after the new EPROM is inserted on the board. Notice that the software version number should be written on the EPROM chip. You may run into a situation where you are installing a new chiller board or replacing an EPROM chip, in which the EPROM on the new chiller board or the new EPROM you are installing has a different software version number than the other EPROMs on the other chiller boards. Different software versions running on a multiple chiller boards system may cause the chiller display keypad to display non-meaningful text due to some earlier software versions that are not compatible with some later software versions. [. . . ] Chiller Staging ­ this menu screen displays how many chillers are in the system, what temperature stage each chiller is in, and if the chiller is set to automatically rotate to a different temperature stage or not. Chiller rotation will result in all compressors to have even run-time. Fault Log ­ this menu screen displays how many faults and the kind of faults a chiller have encountered. Fault History ­ this menu screen displays the most recent system faults, it will store up to latest 300 faults on each chiller. On this screen, press Enter to advance to another chiller Input/Output Log - this menu screen displays information, such as compressors and water pumps runtimes, mininum and maximum in and out loop water temperature, and AC control voltage on each chiller. Chiller On/Off ­ this menu screen lets you select the chiller you want to disable or enable, and push Enter to disable or enable a chiller Output Status ­ this menu screen basically tells you which outputs the controls are calling to turn on or off. Refrigerant Gas ­ this menu screen allows the user to select the type of refrigerant gas that the chiller units contained, so the proper discharge and suction pressure fault limits can be applied if discharge and suction pressure transducers are installed in the chiller system. See below on how to select the type of refrigerant gas being used on each chiller 17 Tempered Water Logic Control Operation & Troubleshooting Manual For MPE-XC Control Panel Some Important Notes To select the type of refrigerant gas used on a chiller unit ­ connect the display keypad to the chiller board that is controlling the chiller unit that is being affected. Under Main menu, scroll down to line item "Refrigerant Gas", press Enter to advance to the Refrigerant Gas menu, then you can select the type of refrigerant gas being used on that chiller unit. You will have to repeat the above process for each chiller unit / chiller board. To calibrate the control AC voltage on a chiller board - connect the display keypad to the chiller board that is being affected, then measure the input power voltage feeding the chiller board. system network - if the system has a network problem, it will display a fault message (Loss of Network), each chiller unit still continue to operate independently. inlet and outlet loop water maximum temperature differential limit In the Cool mode, subtract the loop water out temperature from the common loop water return temperature to obtain the difference. If the difference is 15 °F (-9. 44 °C) or more for 2 minutes and the common loop water return temperature is between 65 °F (18. 33 °C) or less, then the chiller that has the fault will go to a sustained shutdown and display (Exceeded Loop Water Temp Diff Max Limit) and indicate which chiller. In Heat mode, subtract the common loop water return temperature from the loop water out temperature. If the difference is 18 °F or more for 1 minutes and the common loop water return temperature is above 90 °F, then the chiller that has the fault will go to a sustained shutdown and display (Exceeded Loop Water Temp Diff Max Limit) and indicate which chiller. inlet and outlet sea water maximum temperature differential limit In the cool mode the system compares difference between the common inlet and sea water temperatures and generates a fault due to a wide temperature difference. If the common outlet sea water temperature is higher than the common inlet sea water temperature by more than 16 °F (8. 9 °C) and less than 20 °F (11 °C) for 5 minutes, or more than 20 °F (11 °C) for 2 minutes, the chiller will go to a sustained shutdown and the fault message will be (SeaWtr TD Max Limit), and all chillers are disabled. You will need to go to the Chiller On/Off menu to enable all the chillers to make them run. Temperature Sensor Faults The chiller system monitors for defective temperature sensors that are opened, shorted, or sensing a temperature that is out of range. common loop water return sensor - if this sensor is defective, the keypad will display a fault message, and also the fault light and the beeper should turn on. Immediately, the system will monitor the next available common loop return sensor. If all the common return sensors failed, then it will monitor the common loop supply sensor and use it to monitor loop water temperature set points. [. . . ] sea water temperature difference between inlet and outlet of a c hil le r uni t i s too m uc h 1. Chec k for p ro per lo op wa ter fl ow, a nd m ak e s ur e st rainers are not clogged 2. Mak e s ur e the l oop wate r re tur n s ens or i s s ec ur ed to the lo op water return pi pin g 1. Check for proper sea water flow, and make sure strainers are not clogged 2. [. . . ]