OX Series · Onsite Generation / Open Loop Cooling

Generate chlorine
where you use it.

The OX Skid is a fully integrated onsite chlorine generation platform engineered for hyperscale data center cooling. No bulk chemical deliveries, no hazmat storage, no supply chain risk. Your loop sees fresh, on-demand chlorine — produced on the skid, dosed to target, verified in real time.

Request Spec Package → Why Onsite Generation
5–50lb/d
Production Capacity
0
Bulk Chemical Storage
24/7
PID Control + Telemetry
CHEMSTAR / OX-SERIES · REV 2
114" × 66" × 94" (290 × 168 × 239 cm) · ALUMINUM FRAME
The Architecture

Two ways to chlorinate a cooling loop.
Only one belongs in a data center.

Every cooling tower needs chlorine to control biofilm and Legionella. The question is where it comes from. Bulk chemical delivery worked when the building was an office tower. At hyperscale, with hazmat regulations, security perimeters, and uptime requirements, it does not.

Conventional · Bulk Delivery
Trucks. Tanks. Hazmat. Risk.
  • ○Scheduled chemical deliveries through your security perimeter, every few weeks, indefinitely.
  • ○Bulk sodium hypochlorite degrades in storage. Strength drops up to 30% over 90 days; dosing accuracy drifts with it.
  • ○Tank truck logistics, manifest paperwork, and SPCC containment to manage at every site.
  • ○Single-vendor supply chain exposure. One disruption, one missed delivery, one biofilm event — heat transfer efficiency drops, condenser approach rises, and your PUE climbs until someone finds the root cause.
  • ○Vapor exposure for the operations team. OSHA reporting on every spill.
OX Skid · Onsite Generation
Salt, water, and electricity. That's the supply chain.
  • ●Chlorine produced on demand from feed water. Always fresh. No degradation, no drift in strength.
  • ●Eliminates bulk hazmat storage. No SPCC tank, no manifest tracking.
  • ●Smaller security and safety footprint. The only delivery is salt — a non-hazardous commodity.
  • ●Production capacity sized to actual load: 5, 10, 15, 25, or 50 lb/d free available chlorine (FAC).
  • ●BMS Remote Enable/Disable, general alarm, and PID control built in. Native Ethernet IP and Modbus TCP/IP. The skid runs itself.
Specifications

Every line item, documented.

The OX Skid ships factory-configured to your site. Production capacity, storage volume, and recirculation are sized to your actual cooling load — not pre-packaged into compromise.

Standard Build · Onskid
Frame Extruded aluminum
Generator Stainless steel enclosure
HMI Color touchscreen, multi-language
Pre-treatment Onskid filtration, softening, and temperature adjustment
Manifold Recirculation + sampling
Containment Water reuse sump kit
Footprint
114" × 66" × 94" (290 × 168 × 239 cm)
L × W × H
Frame
Extruded aluminum, corrosion-resistant, modular for future upgrades
Onsite mod
Production Capacity
5 / 10 / 15 / 25 / 50
lb/d FAC
Storage Tank
60 / 100 / 125 / 175 / 240 gal · larger off-skid available
Onskid
Control
PID control with fully programmable analyzer
Closed loop
HMI
Color touchscreen on generator, multi-language
Local
Communication
Ethernet IP, Modbus TCP/IP native · additional protocols via optional onskid gateway
Standard
BMS Integration
Remote Enable / Disable, general alarm
DI/DO
Base Probes
Total Chlorine · Free Chlorine · ORP · Pressure
Standard
Optional Probes
pH · Remote ORP · others on request
Add-on
Recirculation
Pumpless standard · optional onskid pump up to 200 GPM
Configurable
Pipe Options
From 1" up to 8" based on site design and needs
Sized
Power
480VAC, 3PH, 60Hz · single power connection (230V available)
Single feed
Ambient Temperature
45°F to 110°F operating
Process
Water Feed Temperature
40°F to 95°F
Feed water
Humidity
10% to 90% non-condensing
RH
Outdoor Option
Containerized system available
Hardened
Sizing

Five capacities. One platform.

The OX Skid scales with your load. Smaller sites get a tight, efficient unit. Hyperscale sites get production capacity that won't have you renegotiating chemistry contracts every twelve months.

5
lb/d FAC
Edge sites · pilot loops · single-cell towers
10
lb/d FAC
Small enterprise · regional facilities
15
lb/d FAC
Mid-tier data centers · multi-cell systems
25
lb/d FAC
Large data centers · campus deployments
50
lb/d FAC
Hyperscale · high-cycle systems · 100MW+ loads
Engineering Choices

Why this skid looks different.

Every line on a spec sheet reflects a tradeoff. Here are the ones we made deliberately, and why each one matters at hyperscale.

Extruded aluminum frame

Most chemical skids use painted carbon steel. We use extruded aluminum because it doesn't corrode in a wet, chlorinated environment and because the modular profile lets your team add or modify skid components onsite without sending the unit back to the factory.

Field-modifiable · Corrosion-resistant · Lightweight

PID control, not pump runtime

The fully programmable analyzer reads actual chlorine residual and adjusts production in real time. Other systems estimate dose from how long the pump ran. We measure the result, not the input.

Closed-loop · Programmable · Auditable

BMS integration

Native comms are Ethernet IP and Modbus TCP/IP. Additional protocols available with optional onskid gateway. Remote Enable/Disable from your BMS. General alarm wired straight to your DCIM. No surprise interface specs three weeks before commissioning.

Native protocols · DCIM-ready · Out of the box

Single power, single connection

One 480VAC 3PH feed for the entire skid (230V also available). One breaker, one disconnect, one sequence on the electrical drawing. Most multi-component skids spread power across three or four feeds, each with its own commissioning complexity.

Single-feed · Faster commissioning
Build Quality

Engineered for the people
who actually maintain it.

Every component on the OX Skid is positioned for visibility, accessibility, and field service. The skid controller, generator, dosing pumps, sensor block, and recirculation manifold are all on a single open face. No hidden valves, no buried fittings, no removing one component to reach another.

01
Color touchscreen HMI
Direct status, alarms, and parameter access at the unit. Multi-language support.
02
XC9 controller
Continuous read of free chlorine, total chlorine, ORP, and pressure with programmable thresholds, alarm logic, and BMS handoff.
03
Sensor manifold
All sensors in one accessible block. Auto-cleaning configurations available; replacement is a five-minute job.
04
Dosing pumps
Optional onskid dosing pumps with configurable flow rate. Front-access cabinets for routine service without disassembly.
05
Onskid pre-treatment
Onskid filtration, softening, and temperature adjustment on the feed water side. Low cost of ownership.
SECONDARY VIEW · SERVICE FACE
OX Skid component layout — service face view showing dosing pumps, electrolytic cell, filtration, and control panel
5 SUBSYSTEMS · 1 ACCESSIBLE FACE
The OX Difference

Eight reasons this skid isn't like the others.

Most onsite chlorine generators share a similar spec sheet. The differences show up in water consumption, lead time, serviceability, and what happens when something needs to change. Here's where the OX Skid separates.

90,000
Gallons saved per year
01 / Zero Water Waste

Every drop through the sensors comes back.

Each analytical probe consumes 7–10 gallons per hour of sample water. Competing designs dump that water down the drain as standard practice. The OX Skid captures all sensor discharge in a waste recapture tank and reintroduces it through a standard reintroduction pump — saving roughly 90,000 gallons per year at typical probe counts. Zero water waste, by design, not by upgrade.

02 / Built to Order

Customized to your site, not the other way around.

Every OX Skid is built to order, allowing pipe routing, connection orientation, capacity tiers, and ancillary components to be configured for your mechanical room — not forced into a one-size-fits-all chassis.

03 / Open Controller

No proprietary lock-in. Your data, your integrations.

The i9 Controller runs open software with native Ethernet IP and Modbus TCP/IP. No proprietary controller platform, no vendor-locked ecosystem, no annual software license. Full BMS integration on day one.

04 / Faster Lead Time

Weeks, not quarters.

Modular design and in-house fabrication compress lead times well below industry average. When your construction schedule accelerates, the skid keeps pace.

05 / Modular Aluminum Frame

Extruded aluminum. Reconfigure, expand, relocate.

The structural frame uses extruded aluminum profiles instead of welded steel. Components bolt in place — swap a subsystem, add capacity, or relocate the skid without cutting and re-welding. Lighter weight, corrosion-resistant, and field-serviceable.

06 / Twin Softener

Dual softeners. Redundancy built in, scaling kept out.

Twin alternating softeners ensure continuous soft water supply to the electrolytic cells — no hard water bypass during regeneration. Less calcium, less cell scaling, longer cell life, and zero downtime from softener changeover.

07 / Ultrasonic Tank Sensors

No floats. No sticking. No false readings.

Tank levels are measured by ultrasonic sensors instead of mechanical float switches. No moving parts to foul, stick, or corrode. More accurate, more reliable, and zero maintenance in chemical-contact environments.

08 / Smaller Footprint

More capacity per square foot of mechanical room.

Vertical component stacking and efficient subsystem layout deliver the same production capacity in a smaller footprint than competing designs — critical when mechanical room real estate is limited or expensive.

Where It Runs

Built for cooling loops that can't stop.

01 / DATA CENTERS

Hyperscale and colo

Open-loop evaporative cooling on hyperscale and colocation campuses. Eliminates bulk chemical exposure inside the security perimeter and reduces hazmat reporting on multi-site portfolios. Also applicable for closed-loop systems with onsite water storage tanks where stagnation and microbial growth are a concern.

02 / HEALTHCARE

Hospitals and healthcare campuses

Integrated Legionella control across cooling towers and potable water systems. Documented dosing for Joint Commission and ASHRAE 188 compliance, without the legal exposure of bulk chemical storage on campus.

03 / INDUSTRIAL

Food, pharma, and manufacturing

Process water and cooling for food, pharma, and heavy manufacturing where consistent residuals matter and where regulatory inspection of chemical storage is a recurring cost.

How We Work

We work with your
mechanical team. Not around them.

Most chemistry vendors hand you a spec sheet and walk away. We sit at the table during design.

Our engineering team reviews drawings, coordinates with the mechanical contractor, and accommodates site-specific requirements — pipe runs, equipment room constraints, electrical routing, BMS architecture. Every OX Skid is configured to the building, not retrofit to fit it.

Drawing review
Pre-fabrication
Site coordination
Design-thru-startup
Custom configuration
Per-site basis
"
Chemstar was the easiest to work with — delivering significant value with a solid say-do ratio.
PE
Project Executive
Mechanical Contractor · Northern Virginia
Frequently Asked

Questions from operators
who run real load.

How does onsite generation actually work? +
The OX Skid uses electrolysis to convert a salt brine and pre-treated feed water into a chlorine solution at the strength your loop needs. The generator runs on demand, controlled by the analyzer measuring actual chlorine residual. Inputs are salt, water, and electricity. There is no bulk hypochlorite to store, no degradation between deliveries, and no hazmat truck on your delivery schedule.
How do we size the right capacity for our site? +
Sizing is a function of your cooling load, makeup water chemistry, and target free chlorine residual. Our applications team will run a sizing analysis from your tower data and recommend a production capacity (5, 10, 15, 25, or 50 lb/d FAC) and storage tank size. We typically recommend sizing slightly above current load to accommodate growth without re-skidding.
Can the skid integrate with our BMS or DCIM? +
Yes. Native comms are Ethernet IP and Modbus TCP/IP. Additional protocols such as BACnet are available with an optional onskid gateway. Remote Enable/Disable is wired for your BMS and there is a general alarm output. We provide point lists and integration documentation as part of the spec package.
Can we deploy outdoors or in non-conditioned space? +
Yes. The standard skid operates in 45°F to 110°F ambient with feed water between 40°F and 95°F. For fully outdoor or harsh-environment sites, we offer a containerized OX Skid in a hardened enclosure with climate control. Storage tanks can also be relocated off-skid for sites with constrained equipment rooms.
What does ongoing service look like? +
Standard service includes routine site visits with documented chemistry analysis, scheduled service of the generator and probes, salt resupply coordination, and 24/7 remote monitoring with alarm response. Routine maintenance is mostly verification rather than rebuild. We staff service across the major US data center corridors with regional partners for surge coverage.
How does pricing work? +
Capital cost for the skid is sized to production capacity and configuration options. Ongoing service is structured as a program agreement that includes monitoring, scheduled service, and salt resupply. We do not separate the equipment from the program; they're engineered together and priced as a system. Send us your site profile and we'll respond with a complete spec and cost projection.
Begin Engagement

Engineered chemistry,
at the scale you operate.

Send us your site profile. We'll respond with a complete OX Skid specification, BMS integration documentation, and a defensible cost projection — built around your actual cooling load.

Request Spec Package → (800) 364-7177