Short answer: The parts most often replaced on a dosing pump are the suction and discharge assemblies, check valve set, hose kit and head assembly; on mechanical diaphragm EMD pumps, the diaphragm is also a regularly replaced part. The right part is chosen according to the pump’s series and capacity: for example, the 3.5 and 10 L/h models in the Nova series use 4×6 mm suction and 4×7 mm discharge connections, while on the 25 L/h model both sides are 9×12 mm. For part replacement, send us a photo of your pump’s label and the part that needs replacing through our contact page or on +9+90 216 606 44 72 / WhatsApp +9+90 532 542 81 24.
On any chlorine dosing pump model, the wetted parts wear over time; replacing them returns the pump to its catalogue flow and pressure values. This page describes the part replacement work covered by our chlorine dosing pump service.
Which Part Is Replaced for Which Symptom?
A part is replaced when it shows a symptom that cleaning does not cure. The table below summarises the parts with their function and the signs that they need replacing.
| Part | Function | Sign that replacement is needed |
|---|---|---|
| Suction assembly | Draws the chemical from the tank through a foot filter into the suction hose | Foot filter that cleaning does not clear, cracked body, suction line constantly drawing air |
| Suction assembly with level sensor | In addition to suction, reports the tank level to the pump | Alarm when the tank is full, no alarm when the tank is empty, sensor sticking |
| Discharge assembly | Delivers the chemical into the line through the injection point | Blockage with crystals, line water flowing back into the discharge hose, leaks |
| Check valve set (lower and upper) | Ensures the chemical flows in one direction only in the head | Loss of flow that cleaning does not cure, frequently recurring air locks |
| Head assembly | The chamber from which the chemical is pumped; the check valves and connections fit onto it | Cracks, damaged threads, leaks around the head |
| Diaphragm | The flexible part that pushes the chemical with each stroke | Leak between the head and the housing, loss of flow that persists after cleaning |
| Hose kit | Carries the suction, discharge and air-bleed connections | Hardening, discolouration, cracks, crushing at the ends |
| Peristaltic hose (Aspendose) | The hose squeezed by the rollers, through which the chemical passes | Drop in flow, cracks in the hose or loss of elasticity |
Before replacement, make sure the part really is worn: hypochlorite crystals clog the check valves and foot filter, producing symptoms similar to wear, and rinsing with clean water is often enough.
Which Part Fits Your Pump? Model and Capacity Compatibility
The compatible part is determined by the pump’s series and capacity; different capacities in the same series may use different connection sizes and head assemblies. The table shows the compatibility given in the catalogue.
| Pump and capacity | Suction connection | Discharge connection | Head assembly |
|---|---|---|---|
| Nova (A, D, DMPR, DMİA) 3.5 L/h 20 bar | 4×6 mm | 4×7 mm | 40 |
| Nova (A, D, DMPR, DMİA) 10 L/h 10 bar | 4×6 mm | 4×7 mm | 40 |
| Nova (A, D, DMPR, DMİA) 25 L/h 5 bar | 9×12 mm | 9×12 mm | 70 |
| Lara (all types) 2 L/h 10 bar | 4×6 mm | 4×6 mm | 40 |
| Lara (all types) 2 L/h 20 bar | 4×6 mm | 4×7 mm | 40 |
| Lara (all types) 5 L/h 7 bar and 10 L/h 5 bar | 4×6 mm | 4×6 mm | 50 |
| Optima A 5 L/h 10 bar | 4×6 mm | 4×6 mm | 50 |
| Optima A 2.5 L/h 15 bar | 4×6 mm | 4×6 mm | 40 |
| Nano A 2 L/h 10 bar and 5 L/h 5 bar | 4×6 mm | 4×6 mm | Nano-specific ECO head assembly |
For example, the AnTech Nova D 25 L/h 5 Bar Digital Dosing Pump requires 9×12 mm suction and discharge assemblies, a 9×12 hose kit and a size 70 head assembly. The AnTech Nova A 10 L/h 10 Bar, on the other hand, comes with a 4×6 mm PVDF suction assembly with level sensor and a 4×7 mm PVDF discharge assembly. In the Lara series, the discharge connection differs only on the 20 bar model: the AnTech Lara A 2 L/h 20 Bar Analogue Dosing Pump uses a 4×7 mm discharge assembly.
Material and seal selection
According to AnTech’s code tables, the suction and discharge assemblies are PVDF in the Nova series and PP in the Lara, Optima and Nano series; in the Nova, Lara and Optima series the pump head is PVDF. On the standard models in the catalogue the O-rings are Viton, and EPDM and Teflon options are also available. Head assemblies are listed with Viton, EPDM and Teflon seals, and suction and discharge assemblies are also listed under separate codes according to seal and body material. For the AnTech Optima A 5 L/h 10 Bar Analogue Dosing Pump – Teflon O-Ring, suction and discharge assemblies with Teflon seals are listed separately. The seal on the replacement part must be the same material as the existing seal on the pump; if you are unsure, tell us your chemical and we will check it together.
Parts for mechanical and peristaltic pumps
On EMD pumps the diaphragm is selected according to pump size: 66 mm on the EMD-P 14, 32 and 49 L/h models; 110 mm on the EMD-M 50, 100 and 150 L/h models; 120 mm on the 200 and 310 L/h models; and 140 mm on the 420 and 630 L/h models. Check valves (cartridge sets) are listed separately as lower and upper, according to head material (PP, PVC, PVDF or stainless steel head). For electromagnetic pumps (Nova, Lara, Optima, Nano), the catalogue does not list a separate diaphragm item; if a diaphragm fault is suspected on these pumps, we will determine together which part needs replacing for your model. On peristaltic Aspendose pumps, the wear part is the hose kit.
Why Do Original Parts Matter?
Original parts preserve the values the pump was designed for in terms of size, material and internal design.
- Size: 4×6 mm and 4×7 mm hoses have the same inner diameter but different outer diameters. The wrong size can cause a leak at the connection or the hose coming loose.
- Material: Viton, EPDM and Teflon seals have different chemical resistance. An unsuitable seal can swell, harden or leak.
- Flow rate: Head assemblies are specific to capacity. An incompatible head or check valve can change the pump’s catalogue flow rate.
- Calibration: After a part is replaced, the pump’s actual flow rate is measured; on digital Nova models, capacity calibration is renewed. Details are on our AnTech dosing pump calibration page.
As the official distributor of AnTech in Türkiye, AQUABELLA matches parts to the pump’s model name and capacity. The series pages list the box contents and compatible parts for each pump: AnTech Nova, AnTech Lara, AnTech Optima and AnTech Nano.
What Information Should You Send for a Part Replacement?
To choose the right part, a photo of the pump’s label and a photo of the part to be replaced are a good start.
- A photo of the pump’s label (with the model name and code legible).
- A photo of the part to be replaced and, if known, the code on it.
- The chemical you use and its concentration.
- The seal material on the pump, if known (Viton, EPDM or Teflon).
- The symptom that led you to replace the part.
To start from the symptom, see our dosing pump repair page, and for regular checks, our dosing pump maintenance service page.
Sources
- AnTech 2025 Product Catalogue (KT_25 R02): spare part and option lists on the series pages, material code tables and the “Spare Parts” section.
Frequently Asked Questions
Which suction and discharge assembly fits my pump?
It depends on the pump's series and capacity. Nova 3.5 and 10 L/h models use 4x6 mm suction and 4x7 mm discharge connections, Nova 25 L/h models use 9x12 mm connections on both sides, and on Lara, Optima and Nano models the suction is 4x6 mm. If you send us a photo of the label, we will determine the right assembly together.
Do you replace diaphragms?
The diaphragms of mechanical diaphragm EMD pumps are listed in the catalogue as separate parts by pump size. For electromagnetic pumps, the catalogue does not list a separate diaphragm item; if a diaphragm fault is suspected on these pumps, send us your model and the symptom, and we will determine together which part needs replacing.
How do I choose between Viton, EPDM and Teflon seals?
The choice depends on the chemical you use. The standard models in the catalogue have Viton seals; EPDM and Teflon options are also available. The seal on the new part must be the same material as the existing one on the pump. Tell us your chemical and we will check the right material together.
Can I replace the part myself?
You can replace parts such as hoses and the suction and discharge assemblies yourself by following the instructions. First disconnect the power, relieve the pressure in the discharge line, and wear gloves and goggles. After replacing the head or check valves, measure the pump's flow rate; if you are unsure, write to us.
How can I send a spare parts request?
Send the label and part photos, together with your chemical, via the contact form or the WhatsApp line +9+90 532 542 81 24; you can also call +9+90 216 606 44 72. We will match the part to your pump's series and capacity and get back to you.