AstralPool Rolachem H Block – Part 521015

Genuine AstralPool H Block, part number 521015, designed for use inside the pump head of compatible Rolachem peristaltic dosing pumps.

The H Block is the rotating roller carrier that helps move chemicals through the pump's squeeze tube. As the block rotates, its rollers compress the tube against the pump head housing, creating the pumping action required for chemical dosing.

The H Block is an important component of your dosing pump and should be inspected if your pump is not delivering chemicals correctly.

Product Specifications

• Brand: AstralPool (Fluidra)

• Part Number: 521015

• Product Name: H Block

• Function: Rotating roller carrier inside the peristaltic pump head

• Compatible Models: Rolachem RC1, RC9, and E Series Chlorinator

Signs Your H Block May Need Replacing

A damaged or broken H Block can affect the performance of your Rolachem dosing pump.

Common signs of a faulty H Block include:

• The pump motor runs, but chemicals are not being dosed.

• A roller is missing, seized or no longer rotates freely.

• The H Block is cracked or one of its arms has broken.

• Chemical dosing is inconsistent or the output has dropped significantly.

Important: If the motor does not turn at all, the problem may be related to the motor, gearbox or control board rather than the H Block.

Other possible causes of dosing problems include a damaged squeeze tube, a cracked pump head, a disconnected tube or an empty chemical container.

Check the Squeeze Tube Before Replacing the H Block

The squeeze tube is a wear component in a peristaltic dosing pump and should be inspected whenever the H Block is replaced.

If the H Block has broken, check the squeeze tube carefully for damage or deterioration before installing the replacement. A worn or damaged tube, or debris left inside the pump head, may affect the operation of the new component.

Important: Chlorine and acid squeeze tubes are different parts. Never use the same tube or pump head for both acid and chlorine dosing.

Frequently Asked Questions

What does the Rolachem H Block do?

The H Block is the rotating roller carrier inside the pump head of a peristaltic dosing pump. Its rollers compress the squeeze tube as they rotate, moving chemicals through the tube and into the dosing system.

My Rolachem pump motor runs, but no chemicals are being dosed. Could the H Block be faulty?

Yes. A broken roller or damaged H Block can prevent the pump from dosing correctly. However, the problem could also be caused by a worn or disconnected squeeze tube, a cracked pump head or an empty chemical container. Inspect these components before ordering a replacement.

How many H Blocks do I need?

The quantity depends on your pump model. The listed requirements are one H Block per pump head for the RC9, RO9 and RP9, and two for the RC8.

Check your pump model and existing configuration before ordering.

Should I replace the squeeze tube at the same time?

It is recommended that you inspect the squeeze tube whenever you replace the H Block. If the tube is worn, damaged or deteriorated, replacing it at the same time can help prevent further problems.

Is H Block 521015 compatible with Viron eQuilibrium dosing systems?

Compatibility should be confirmed before ordering. Although some pump head components are shared across different AstralPool systems, the 521015 H Block is listed for Rolachem pumps.

If you are unsure whether this part suits your system, check your pump model and existing component before ordering.