Wilo Circulator Pump TOP-Z 40/7 2046637

The Wilo TOP-Z 40/7 is a glandless circulator pump built for drinking water circulation. It is designed for domestic hot water circulation systems in industry and building services, and is suitable only for drinking water. The pump moves hot water around a circulation loop so that draw-off points receive hot water without a long wait.

• The circulation loop runs cold or takes noticeably longer to deliver hot water at the tap.
• The pump is noisy in operation, with rumbling, grinding or rattling from the motor or bearing area.
• Water weeps from the pump housing, flange joints or the motor seal area.
• The pump runs hot, trips repeatedly or fails to start when the circuit calls for circulation.
• Flow through the loop is weak or intermittent despite the circuit being open and correctly vented.

• Confirm the part number 2046637 and the alternative number 1975178 against the pump currently fitted.
• Check the pump connection is DN 40 and the port-to-port length is 250 mm, so the replacement matches the pipework without alteration.
• Check the system water hardness against the maximum permitted total water hardness of 3.57 mmol/l (20°dH).
• Confirm the electrical supply is 1~230 V, 50 Hz and that the ambient temperature at the installation point stays within 0 °C to 40 °C.