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Sentinel X400 System Restorer is specifically designed for cleaning older closed loop hydronic heating systems. It is a non-acid treatment which restores circulation to radiators and pipework. Its ruthlessly efficient formula shifts built-up magnetite sludge, eliminating cold spots in radiators and restoring proper heat distribution.

  • Restores systems suffering with circulation problems
  • Eliminates radiator cold spots
  • Prepares older systems for the installation of new components
  • Has a non-acid formula which does not cause pin-holing or leaks
  • Can be used in all types of indirect heating systems, including those containing aluminium
1 quart of Sentinel X400 is sufficient to treat a typical residential system of 25 gallon. Larger systems should be dosed at 1% of system water. To clean an existing system, Sentinel X400 should be circulated, preferably at normal operating temperature, with all valves open and the pump turned to maximum flow for a minimum period of 2 hours or until satisfactory performance is restored.

Where systems are badly fouled, a longer period of circulation (e.g., up to 4 weeks) is recommended, but the product will not clear a completely blocked pipe. There is no limit to the time for which the product can safely be left in the system.

Rapid cleaning may be carried out if Sentinel X400 is used in conjunction with a power-flushing device.

Flush the system before refilling and treating with Sentinel X100 Inhibitor.
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Product Type:
32 oz.
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