Click here to download the full Cross Reference Chart Select any of the following Series of IRC/WELWYN to view it’s HTR- Equivalent(s): PW-20 TO PW-40 PWRL OAR WA 84F PPW/CAW WSM2/WSM3 AS-SM PW PWR, PWR/SQM, PWR/SRM WA 87/T SPP PWW/CW LOB PLO/LPW WP-S/WA80/AS/W30 WP-S W-3123 OARSZ, OARS,OARS-XP EBW8518 WA 80Z/AS-SM