Honeywell Discontinued: Valve proving system A4021
The A4021 is a self-checking microprocessor based Valve Proving System (VPS). The A4021 checks the effective closure of automatic shut-off valves by measuring the differential pressure between two valves during the test sequence.
The A4021 is specially designed to be used as proving system to check the effective closure of the valves before burner start up (pre-configuration) or at the end of a heat demand (post-configuration).
Approvals: CE approved (50Hz) according EN1643:2000 (spare part ONLY for non-MD applications installed before 2017)
Protection class: IP40, only with subbase ZL030001
Ambient temperature: -10...60C
Maximum humidity: 95%rh
Alarm output potential free NO contact.
Uses the NO contact of a standard gas pressure switch, that is set to 1/2x the nominal inlet pressure.
Suggested gas pressure switches: C6097 series C60VR40xxx series DG series
Note: To be used in Europe only as spare part. For new installations the Kromschroeder TC 2 or TC 3 can be used. For details visit http://www.docuthek.com (copy/paste link into web browser)
Comment: Test time per valve 25sec.