Rule shower drain box rubber non-return valve (joker valve) fits into the Rule Shower Drain Pump Systems preventing water back flow to the pump in the Rule Shower Drain Pump Systems.
In 2018 the Rule Shower Sump Boxes were updated to incorporate the redesigned Rule Bilge Pumps and in turn, the non-return valve was changed. The older boxes without the threaded ports use the WA411 (1240R M-1086) Non-Return Valve and the new models with the threaded ports use the EC337C (1223R) Non-Return Valve.
The valves are not interchangeable between the new and old shower sump boxes.
The original part number for the check valve for the 97A and 98A Rule Shower Drain Sump was M-1086, which has now been superseded by part number 1240R. Both parts are the same, only the part number has changed.
WA411 | EC337C | |
Diameter | 19mm | 28mm |
Length | 31mm | 30mm |
Suitable For | Rule 97A and Rule 98A Shower Sumps (Smooth Outlet Connections) | Rule 98B and Rule 99B Shower Sumps (Threaded Outlet Connections) |
Original Part Number | M-1086 |