Howden’s technical support team is responsive. Send an email to their service address with the model number (XRV 127) and serial number. Attach a photo of the nameplate if possible. They typically reply within 48 hours with a secure download link.
The official manual provides:
Operates using differential pressure between suction and discharge to force oil from the separator into the compressor. Bearing Design: howden xrv 127 manual
Capacity Loss: Often related to slide valve calibration issues or internal bypass leakage. Safety and Compliance Howden’s technical support team is responsive