Every commercial softener in Saudi Arabia runs on water softener salt, and how much it burns through is one of the best clues to whether it was sized well. A unit that is too small regenerates too often, eats salt and leaves the building on untreated water more than it should. A unit that is too big costs more than it needs to. This guide looks at the larger Regal models we supply in the Kingdom, the Regal 500, Regal 750, Regal Twin 3672 and Regal Duplex 3072, and explains how hotels, compounds, hospitals and factories should choose between one vessel, two alternating vessels and two vessels in parallel.
TL;DR
- Salt use, regeneration frequency and supply during regeneration are linked. Size for all three, not just flow.
- One vessel cannot treat water while it regenerates. Delayed regeneration at night suits sites that close.
- The Regal Twin 3672 alternates its two vessels, so a hospital or 24-hour hotel never runs on untreated water.
- The Regal Duplex 3072 shares the load across two vessels at once for higher peak demand.
- Most Regal valves accept inlet water from 4 to 30 °C. The Duplex 3072 is rated up to 43 °C, which matters for warm tanks in summer.
Got a big site in Riyadh, Jeddah or the Eastern Province? Talk to Our Team with your water analysis and daily use.
Contents
- Why Saudi sites need careful sizing
- Water softener salt and regeneration explained
- Which Regal suits which building
- Heat, tanks and the inlet temperature limit
- Sizing steps for a Saudi site
- FAQs
Why Saudi sites need careful sizing
Municipal water in much of the Kingdom starts as desalinated seawater, and research published through the Saline Water Conversion Corporation describes how product water is treated and blended before it reaches users (SWCC, Al-Hamzah and Fellows 2024). Where groundwater or tanker deliveries make up part of the supply, hardness can vary from week to week. A softener sized on one good sample can fall short when the blend changes.
The national standard for unbottled drinking water sets total hardness at no more than 320 mg/L as calcium carbonate (KSA Unbottled Drinking Water Standard 2024). Water within that limit can still scale boilers, calorifiers, cooling plant and kitchen equipment, which is why the treated side of a building matters. Our post on hard water in Saudi Arabia covers where the hardness comes from.
So use a recent water analysis, ideally more than one, and size to the harder figure.
Water softener salt and regeneration explained
A softener holds a bed of resin or Ecomix media that captures calcium and magnesium. When it is full, the valve draws brine from the salt tank, rinses the bed and puts the captured minerals to drain. That is regeneration.
The Regal 750 datasheet gives a salt dose of 7.5 to 12 kg for each regeneration, and the unit treats 15 m³ between regenerations. Those two numbers let a facilities team estimate how often the brine tank needs filling. On a large twin or duplex set, each vessel has its own 570 litre brine tank, so think about where pallets of salt will be stored and how they reach the plant room.
Salt quality also matters. Use the salt grade your installer specifies, keep bags dry and check the brine tank on every service visit. Our Comprehensive Maintenance plans include those checks.
Which Regal suits which building
Each model answers a different question.
Regal 500. A single 10 x 54 vessel on a CE one inch valve with metered regeneration. It ships without media, so Ecomix or cation resin is chosen to suit your analysis. Its quoted 6.12 m³/h is the flow the valve passes at a 1 bar pressure drop, not an operating rating. The datasheet places it in domestic and light commercial duty.
Regal 750. A bi-block single unit loaded with 75 litres of PC002 resin. It runs at 3.5 m³/h, peaks at 4.3 m³/h and treats 15 m³ between regenerations. The datasheet aims it at hospitality, healthcare, estates and light industry.
Regal Twin 3672. Two 36 x 72 vessels on a two inch valve, working in turn. One treats while the other regenerates or waits, so supply never drops. It passes 18.2 m³/h at a 1 bar drop, and each vessel takes 700 to 725 litres of resin or around 600 litres of Ecomix, quoted to your water.
Regal Duplex 3072. Two 30 x 72 vessels working together on a Clack WS2PCI valve, rated for 15 m³/h duty, or 7.5 m³/h per vessel. Each vessel holds around 425 litres of resin. Duplex builds are listed as an option on the Regal Twin 3672 page, and the 3072 is quoted from its datasheet, so ask for it by name.
Need help matching one of these to your building? Request a Quote and include your analysis and meter readings.
| Building type | Typical pattern | Likely starting point |
|---|---|---|
| Office tower or school | Closes at night, modest peaks | Single Regal 750 with night regeneration |
| Hotel or serviced apartments | Round-the-clock use, morning peak | Regal Twin 3672 |
| Hospital or care facility | Never stops, cannot run untreated | Regal Twin 3672 |
| Factory with shift peaks | High flow for short periods | Regal Duplex 3072 |
| Villa compound | Varies, often several plant rooms | Depends on layout, quoted per site |
This table is a starting point only. The final choice depends on your hardness, daily volume and peak flow. For process plant, see our guide to controlling water hardness on a production line.
Heat, tanks and the inlet temperature limit
This is where Saudi sites differ most from cooler markets. The Regal 500, 750 and Twin 3672 datasheets all set an inlet range of +4 to +30 °C. Water standing in a rooftop or ground tank through a Riyadh or Dammam summer can warm up a lot, and a softener fed above its rated range may not perform as the datasheet says.
The Regal Duplex 3072 has a wider range of +4 to +43 °C and accepts 1.4 to 8.6 bar. Where the feed comes straight from a hot tank, that model, or a softener placed on a cooler part of the system, is worth discussing at survey stage.
Ask your contractor to measure the feed temperature at the planned softener position in the hottest months. Put the result on the specification. Our commercial water softener specification guide explains bypass, drain and backflow points.
Weight is the other plant room check. Dry, the 750 weighs 100 kg, the Duplex 3072 220 kg and the Twin 3672 280 kg, before media, water and salt.
Sizing steps for a Saudi site
- Get one or more recent water analyses, including hardness, iron and manganese. The datasheets set feed limits of 750 mg/L hardness, 0.2 mg/L iron and 0.05 mg/L manganese.
- Note whether the site takes tanker water as well as mains, and how often.
- Read the meter for a busy week and work out the daily volume on the treated side.
- Find the peak flow, for example at shift change in a hospital or the morning rush in a hotel.
- Decide whether the site can ever accept untreated water. If not, plan a twin set.
- Measure the feed temperature in summer at the planned position.
- Check the plant room: height, floor loading, drain and a 230 V supply.
Smaller sites such as cafés and clinics are better served by our guide to the Regal 100, 150 and 200. For the full range, see our water softener salt and Regal softener page.
FAQs
How much salt does a commercial softener use?
It depends on the model and how often it regenerates. The Regal 750 datasheet gives 7.5 to 12 kg per regeneration. Harder water and higher use mean more regenerations and more salt.
Can a softener handle warm water from a roof tank?
Only within its rated range. Most Regal models accept 4 to 30 °C. The Duplex 3072 accepts up to 43 °C.
What is the difference between twin and duplex?
A twin set uses one vessel at a time and keeps the other ready, so supply never stops. A duplex set runs both vessels at once to carry more flow.
Does tanker water change the sizing?
It can. Tanker and well water may be harder than desalinated mains, so size to the harder analysis.
Do you offer a site survey?
Yes. A site survey is chargeable, and it confirms the layout, drain, power and feed temperature before we quote.
Ready to plan your softener?
Share your water analysis, a week of meter readings, your peak flow and a few plant room photos. We will recommend single, twin or duplex duty and quote it. Get in Touch with our team in the Kingdom.
Sources
- SWCC, Al-Hamzah and Fellows (2024): https://www.swcc.gov.sa/uploads/water-16-01810%20(3).pdf
- KSA Unbottled Drinking Water Standard 2024: https://hse.kaust.edu.sa/wp-content/uploads/2024/11/Unbottled-Drinking-Water-Standard-KSA-2024.pdf
- Sovereign Water datasheets: Regal 500 (SWC-REG500-25-R0), Regal 750 (SWC-REG750-26-R0), Regal Twin 3672 (SWC-RF3672TW-26-R0), Regal Duplex 3072 (SWC-RF3072DX-26-R0)
