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AQUAIOT
Caustic Soda Dosing

Caustic that crystallises
should not stall your dose.

Sodium hydroxide is thick, it drops crystals when the chemical store gets cold, and those crystals settle in the small valves inside a metering pump. A MAC dosing valve doses it into a pressurised line with no check valves to gum up.

Authorised by MAC Valves Inc. for UK and Ireland
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MAC LBV · Dosing Feed
Live
MAC Liquid Bullet Valve BV214 double-diaphragm dosing valve
12.4 Pulses/sec
0.02 Drift %
BV214 Valve Core
Dosing Active

The case for change

Why caustic blocks small dosing pumps

Strong caustic is viscous, and it crystallises as the ambient temperature falls. The crystals lodge on ball check valves and in the pump head, so the stroke goes short and the dose goes light. Correction then arrives as pulsed slugs, and the pH you were trimming overshoots the other way.

01

Pulsation errors costing you compliance

Stroke-based pumps create pulsation at low flows, causing dosing inaccuracy, downstream mixing problems, and dose logs that cannot be defended in an audit.

02

Tubing failures and unplanned downtime

Peristaltic tubing splits under chemical exposure. Every failure means a reactive call-out, replacement parts, and a window where dosing has stopped entirely.

03

High maintenance across multiple failure points

Check valves, diaphragms, tubing, and motors all need regular servicing. Each failure point is a separate maintenance task and a separate cost line.

04

Accuracy drift as components wear

Pump accuracy degrades as internals wear. The further from original design point, the worse the drift, and the harder it is to keep dose logs within spec.

Engineering architecture

Four precision advantages inside every MAC Liquid Bullet Valve

Hover each capability to see the system respond in real time.

MAC LBV · Live System Monitor
Active
0.02 Drift %
12.4 Pulses/sec
OK Seal integrity
6.2 Bar inlet
Dual diaphragm isolating media · Chemical barrier active
MEDIA D-Flex D-Flex
01

Dual D-Flex Diaphragm

Media contacts only the diaphragm faces and valve body. No sliding seals, no o-ring rub, no tubing in the flow path. Chemical isolation by design.

PTFE / FKM / EPDM Media-separated No seal wear
P1 P2 Balanced
02

Balanced Poppet

Upstream pressure variation is equalised at the seat. Dosing volume per pulse stays consistent regardless of supply fluctuations, over the full life of the valve.

Pressure-independent Zero drift
ON OFF PWM · 4-20mA · On/off
03

High-Speed Solenoid Actuation

On/off switching, pulse-width modulation, or proportional control. Fast cycling creates near-continuous micro-dosing from a valve-sized footprint.

On/off & PWM Proportional 4-20mA
Multi-channel manifold block
04

Manifold Integration

A single block serves multiple dosing channels from one connection point, replacing the wiring, tubing, and floor space of individual pump assemblies.

Multi-channel Cartridge internals
0 bar
Max working pressure (app. dep.)
0°C
Operating temperature range
0 seals
PTFE, FKM (Viton), and EPDM options
UK Stocked
Standard cores held for rapid dispatch

Smart dosing integration

How AQUAIOT connects MAC valves to your water system

From sensor input to auditable dose log, in four steps.

1

Monitor

AQUAIOT sensors measure flow, conductivity, and water quality in real time. Data streams to the edge controller continuously.

2

Decide

Cloud logic and local edge rules calculate the dosing requirement against set-points, flow conditions, and time windows.

3

Dose

The MAC LBV fires precise solenoid pulses. Pulse width, frequency, and duration are all configurable from the AQUAIOT dashboard.

4

Prove

Every dose event is logged with timestamp, volume and sensor context. Set against your pH trace, the log shows whether a swing came from the process or from the dose.

Integration and control

Built for your existing infrastructure

SCADA and BMS

MODBUS RS485 and API connections. Direct integration with existing control systems without replacing your architecture.

Closed-loop dosing

Flow, conductivity, or quality sensor feedback adjusts dosing in real time. No manual trim, no operator intervention.

Compliance logging

Timestamped caustic dose records alongside pH readings. Exportable evidence for your process, discharge and treatment reporting.

4G and LoRaWAN

Secure cellular telemetry. Encrypted payloads, over-the-air configuration, remote firmware updates.

PWM and proportional

On/off pulse, pulse-width modulation, or 0-10V / 4-20mA proportional control from one valve platform.

Cloud dashboard

Trendlines, alarms, analytics, role-based access, and data export from the AQUAIOT platform.

Caustic duty

Where caustic soda dosing fits

pH correction and alkaline cleaning across treatment, process and CIP lines. Part of the full chemical dosing valve range.

Caustic soda dosing

No ball check valves in the dose path, so the crystals that form in a cold chemical store have nothing to seize.

Proportional delivery rather than slugs, so pH correction arrives steadily and the analyser sees a smoother trace.

Sodium hydroxide

Sulphuric acid

Dense, hazardous acid dosed with no tubing and far fewer wear parts.

pH trim

Food, beverage and CIP

Repeatable sanitiser, caustic and acid dosing, logged for HACCP.

CIP and process

Water treatment plants

Flow-proportional coagulant, pH and chlorine dosing for stable residuals.

Potable and process

Technical overview

BV214 and BV221: full technical reference

Parameter BV214 BV221
Body size14mm21mm
Flow rangeMicro to low L/minLow to mid L/min
Max pressure~8 bar (app. dep.)~10 bar (app. dep.)
ActuationSolenoid: on/off, PWMSolenoid: on/off, PWM
ElastomersPTFE, FKM, EPDMPTFE, FKM, EPDM
Temp. range0 to 80°C0 to 80°C
ManifoldSingle / multi-channelSingle / multi-channel
ConnectionG-thread / customG-thread / custom
MediaWater, fertilisers, detergents, reagents, gases
Control signalOn/off, PWM, proportional (0-10V / 4-20mA)
ATEX variantsAvailable, contact us with zone classification

Exact specifications depend on body, orifice, and elastomer selection. Contact us for application-specific sizing and ATEX requirements.

Why choose AQUAIOT

Factory-authorised. Engineering-supplied. UK-stocked.

Authorised MAC Valves UK and Ireland distributor

As part of PSI Technologies, AQUAIOT holds factory-backed authorisation. We specify, stock, and support MAC dosing valves across the UK and Ireland.

Our engineers configure every build

Bespoke valve selection for unusual media, pressure, or manifold requirements. P&ID review included.

UK stock and rapid supply

Standard configurations held in UK inventory for rapid dispatch. No lengthy lead times on core SKUs.

End-to-end delivery

Hardware specification, IoT integration, cloud dashboard, commissioning, and ongoing support all from one team.

Open and interoperable

SCADA, BMS, CAFM, and AQUAIOT ecosystem integration via MODBUS, RS485, and API. No lock-in.

PSI Technologies Group

AQUAIOT operates as part of PSI Technologies, making us the exclusive MAC Valves partner for liquid dosing applications in the UK and Ireland. Every solution combines factory-authorised valve hardware with AQUAIOT IoT integration, cloud dashboards, and our own engineering team on every project.

  • Factory-authorised MAC Valves supply and specification
  • AQUAIOT IoT integration included as standard
  • UK-held stock for standard configurations
  • Engineering team covers design, install, and commissioning
  • Cloud monitoring, audit logging, and SCADA integration
  • Post-installation support and remote diagnostics

Common questions

Caustic soda dosing valve questions

Because strong sodium hydroxide is viscous and crystallises as it cools. The crystals lodge on the ball check valves and in the pump head, so the stroke delivers less than the setpoint says. A dosing valve has no check valves in the dose path and works against line pressure, which removes the parts caustic tends to seize.
It helps. A pulsing pump delivers caustic in slugs, so pH swings and the control loop chases it. The valve doses proportionally on a PWM or analogue signal without pulsation, so correction arrives as a steady stream and the analyser sees a smoother trace. Mixing and loop tuning still set how tight the trim can get.
Cold storage is where caustic dosing usually fails, because crystals form in the suction line and the pump head. The valve doses into a pressurised line and there is no suction stroke to starve, but the store, line and dilution still need designing for the temperature. Confirm concentration and temperature with an engineer.
BV214 and BV221 cores cover micro-litre to low-L/min dosing at up to roughly 8 to 10 bar, depending on orifice, body and elastomer selection.
The balanced poppet equalises upstream pressure variation, so dose volume per pulse stays consistent regardless of supply fluctuations, unlike a pump that drifts with wear.
There is no tubing to replace, no check valves to service and no motor wear. Cartridge-replaceable internals mean field service without removing the valve from the manifold.
Yes. MODBUS RS485 and API connections for SCADA, BMS, CAFM and the AQUAIOT cloud platform, with closed-loop control from flow, conductivity or water quality feedback.

Get started

Discuss your caustic dosing

Tell us your caustic strength, dose rate, store arrangement and line pressure. Our engineers will select the right MAC build and integrate the telemetry.

We respond within one working day. No spam, no sales scripts.

Prefer to call? 02392 233611  ·  Full contact page

Caustic soda dosing. No check valves to block, no pH overshoot, UK-stocked and supported by AQUAIOT.

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