OMEGA AIR B-DRY Series, Installation And Operating Manual

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13.2.5 Control Valves Malfunction
The cause of high pressure drop could be malfunctioning control valves. In this case the
pressure in the towers during adsorption phase will be much lower than the inlet pressure. In
this case the control lower control might have to be replaced.
13.2.6 Clogged Pre-filter and/or After-filter
Although the service interval for pre-filter and after-filter is 12
months, the filter might have to be changed before the service
interval if they are clogged. You can check the status of the filter
on the differential pressure indicator on top of each filter housing.
13.2.7 Increased Purge Flow
Description:
Purge flow during one half-cycle is greatly increased compared to the other half-cycle
causing the pressure to drop in both regenerating and adsorbing tower.
Possible causes, inspection and fixing procedure:
1.
Faulty nozzle
: Highly unlikely.
2. Faulty non-return valve : Towers are connected to the outlet piping through non-
return valves and nozzles. In case where non-return valve mechanism is not closed
when the flow is reversed due to mechanical fault or dirt in the valve the condition will
cause considerable depressurization in regenerating and adsorbing tower.
Decommission the dryer (see
11 Decommissioning ) and inspect the non-return valves.
If there is visible dirt on the valve clean it and reinstall it. If there is visible mechanical
wear or damage on the valve order the new non-return valve at your supplier.