Whole House & Building Inlet Systems

Flat and building inlet treatment meets the water on the main line before it is distributed through the installation. A flat inlet feeds a single independent unit, while a building inlet feeds the whole riser; the stages are chosen according to the sediment, limescale and chlorine load, and capacity is set by instantaneous flow rate.

The Difference Between Flat Inlet, Building Inlet and Complex Inlet

All three applications work on the same principle; the difference is where the system is installed and how many users it feeds.

A flat inlet solution is quick and independent; it protects your own plumbing, but limescale keeps building up in the main risers of the building. A building inlet solution lowers the cost per person and protects the whole installation, but it calls for a shared decision, a shared budget and shared responsibility for maintenance.

Why Is Central Treatment Needed?

Mains water passes through many points before it reaches your home, and each point carries its own risk.

• Limescale: Hard water builds up on every heated surface, from the combi boiler heat exchanger to the heating element of the washing machine. Heat transfer becomes harder, energy consumption rises and equipment life shortens.
• Sediment and sand: Mains repairs and the pressure surges that follow an interruption stir up the sediment in the pipes. That sediment blocks aerators, shower heads and valves.
• Rust: In old galvanised installations iron compounds can pass into the water; they yellow white laundry and leave marks on tapware.
• Chlorine: The free chlorine present in mains water creates a difference in smell and taste; it is also noticeable during a shower.
• Risks from the storage tank: Sediment collects in water storage tanks that are not maintained, and the microbiological load can rise.

A central system deals with these items at the point where the water enters the building. Protection is therefore provided from a single point instead of fitting a separate unit to every tap.

Which Stages Make Up a Water Filtration System?

In central treatment the stages are chosen according to the condition of the raw water. The typical chain is as follows:

The order of the stages matters: coarse filters come first and protect the sensitive equipment behind them. Activated carbon is usually placed before softening, because it protects the softening resin from chlorine.

Whole House Water Filters: Single, Twin and Triple Sets

At a flat or building inlet the most common starting solution is the filter sets named after the number of housings.

• Single set: A single-stage sediment filter. It is the economical solution on lines with a sand and rust problem and low hardness.
• Twin set: Activated carbon is added to the sediment filter. Chlorine odour and taste problems are dealt with as well.
• Triple set: Sediment, carbon and a further stage are used together; this gives wider protection.

These sets are built with the large-volume housings known as Big Blue. The advantage of a large housing is a low pressure drop at high flow rate and a longer cartridge life. Because cartridges in standard sizes are widely available, there is no supply problem later on.

Washable steel filters, on the other hand, are removed and cleaned instead of having the cartridge replaced, and are then reused. On lines with a high sediment load they lower the consumables cost, but they need regular cleaning.

How Are Capacity and Flow Rate Calculated?

In central systems capacity is set by peak flow rate rather than by total daily consumption. In an apartment block, several flats drawing water at the same time in the morning is the hardest moment the system has to meet. If that moment is not met, pressure drops and the water weakens on the upper floors.

The headings taken into account in the calculation:

• Number of flats and number of users: These form the basis of total demand.
• Simultaneity: A factor is applied on the assumption that not all flats draw water at the same time.
• Building height: As the number of floors rises, pressure loss and the need for a booster pump set come into play.
• Raw water hardness: This determines the resin volume of the softening stage.
• Is there a storage tank: In systems with a storage tank the system is placed after the tank; pressure and microbiological risk are assessed separately.

Choosing the capacity too small leads to a pressure drop and to frequent regeneration in softening. Choosing it too large means an unnecessary initial investment. The decision must therefore be made with measured hardness and real flow rate data; on the Water Point side the site survey is free of charge if the unit is purchased from us.

Villa and Detached House Inlets

In detached buildings the picture differs from an apartment block. The decision belongs to one person, finding a place for the system is usually easier, and additional consumption items such as garden irrigation come into play.

The points that stand out in villa inlet applications:

• Garden consumption: If the irrigation flow rate is not taken into account, the system falls short in the summer months. In some applications the garden line is taken off ahead of the treatment.
• Well water: Well use is common in detached houses; in that case additional stages are needed for sediment, iron and microbiological risk.
• Swimming pool: Pool feed water is a separate item and calls for its own conditioning.
• Risk of freezing: If the system is installed outdoors, it must be protected against winter conditions.

Our guide to villa water treatment follows the whole chain from the source to the tap.

Installation Location and Plumbing Requirements

A central system is placed immediately after the point where the water enters the building. The following conditions must be met before installation:

• Sufficient space: Room is needed for the tank, the filter housings and the brine tank; clearance must also be left around them for service and cartridge changes.
• Drain line: A suitable drain is essential for softener regeneration and for the backwash of automatic filters. This is the item most often overlooked.
• Electricity: A socket is needed for the automatic valves, the UV unit and the dosing pump.
• Bypass line: A bypass must be installed so that the building is not left without water during service. In apartment block applications this is all but mandatory.
• Floor and drainage: A location with a drain, where a possible leak would do no damage, should be preferred.
• Inlet pressure: If the pressure is low a booster pump set may be needed, and if it is high a pressure reducer may be.

After installation, the hardness and sediment condition of the outlet water must be measured to verify that the target values are met.

Apartment Block Water Treatment Systems: What the Management Must Decide

In building inlet applications, management decisions are as decisive as the technical choice. The following must be clarified before the system is installed:

• Budget and sharing: How the initial investment will be divided.
• Running cost: Whether salt, cartridge and electricity costs will be met from the service charge.
• Person responsible for maintenance: Who will keep track of salt top-ups and cartridge changes.
• Service contract: Whether scheduled maintenance will be put under contract.
• Permission for the location: The decision on the use of the shared area where the system will be installed.
• Fault procedure: Who is to be informed if there is a problem and who will open the bypass.

When these headings are not settled from the outset, even a system installed correctly from a technical point of view is left unmaintained and soon loses its function. In practice the problem seen most often is not equipment failure but salt top-ups and cartridge changes being forgotten. The decisions a building management faces are set out in our guide to building inlet water treatment systems.

Maintenance Intervals

A rising pressure difference across the filter housings is the clearest sign that the cartridge is blocked. When a noticeable drop in water pressure is felt, this is the first place to check.

Common Mistakes

• Buying, or not buying, softening without having the hardness measured: A wrong decision in either direction creates cost.
• Estimating capacity by looking at the number of flats: Peak flow rate and simultaneity must be taken into account.
• Leaving no bypass line: The whole building is left without water during service.
• Not planning the drain line: Regeneration and backwash cannot be carried out.
• Not appointing someone responsible for maintenance: The system is left unmaintained and soon loses its function.
• Not asking about the cartridge size: A non-standard cartridge size creates supply dependence later on.
• Skipping tank maintenance: In systems with a storage tank, if cleaning the tank ahead of the treatment is neglected, the load on the treatment rises.

How the Water Tank and Booster Pump Set Fit In

In most multi-storey buildings the water is first taken into a storage tank and pumped from there to the floors by a booster pump set. This arrangement has a direct effect on where the treatment system is placed.

• The system is installed after the tank: The sediment collected in the tank and any microbiological load that may form there must remain ahead of the treatment, so that the filters can hold that load back.
• Booster pump pressure is decisive: Filter housings and the softener tank work efficiently within a certain pressure range. If the booster setting is too low the water weakens on the upper floors, and if it is too high the equipment is put under strain.
• Pressure loss must be taken into account: Every filter stage creates a certain amount of pressure loss. As the number of stages rises this loss accumulates; this is why large-volume housings such as Big Blue are preferred.
• The tank has its own maintenance: A treatment system does not take the place of cleaning the tank. The tank must be emptied and cleaned periodically; otherwise the load on the treatment rises unnecessarily.

In buildings with no storage tank, fed directly from mains pressure, the system is placed immediately after the water meter, and a pressure measurement must always be taken before installation.

Plumbing in Older Buildings

In buildings put up many years ago, galvanised or iron pipe is common. These pipes corrode from the inside over time; rust and iron compounds pass into the water.

The typical signs seen in such buildings are these:

• The first water from a tap that has not been used for a long time is yellowish or reddish
• White laundry yellows over time
• Brown marks form around the toilet and the washbasin
• Rust particles collect in aerators and shower heads

Central treatment holds these particles back and stops them reaching the taps. There is one point to watch, however: a treatment system protects the line downstream of itself. When the system is installed at the building inlet, the main riser and the plumbing inside the flats are protected, while the section of pipe ahead of the system remains unaffected. This is why the system is preferably installed at the earliest possible point.

What Changes After the System Is Installed?

The results of central treatment show themselves in stages; some immediately, some within weeks.

• Immediately: Chlorine odour decreases, and the taste of the water and the feel during a shower change.
• In the first days: The sediment reaching aerators and shower heads is cut off; once the existing deposit is cleaned away, the flow returns to normal.
• In the first weeks: Soap and detergent lather more easily and less is used. Drying marks on tapware and glass surfaces decrease noticeably.
• Within months: New limescale build-up stops. Existing limescale does not disappear on its own; maintenance of the combi boiler and the water heater is therefore recommended after the system is installed.
• In the long run: The fault frequency and energy consumption of the heating equipment stay close to their first-day level.

Setting the expectation correctly matters: a central system does not strip out limescale formed in the past, it stops new build-up. Existing deposits still need separate cleaning or maintenance.

When Are a Dosing Pump and Conditioning Needed?

In some applications filtration and softening alone are not enough; the water needs a controlled chemical feed. This is done with a dosing pump.

• Antiscalant dosing: Delays limescale crystallisation in membrane systems.
• pH adjustment: Used on waters with a high tendency to corrosion or to limescale.
• ORP-controlled dosing: The oxidation-reduction potential of the water is measured and the feed is adjusted automatically; it works to demand rather than at a fixed dose.

Dosing systems are set up according to the analysis results and need regular monitoring. The choice of chemical, the dose and the point of use must always be determined by a technical assessment.

The Difference Between a Limescale Treatment Unit and Softening

In the market the terms "limescale treatment", "scale inhibitor" and "water softening" are often used interchangeably, but their operating principles can differ.

Water softeners work by ion exchange: calcium and magnesium are actually taken out of the water and replaced by sodium. The hardness of the outlet water drops measurably and can be verified with a test kit.

Industrial-type limescale treatment systems differ in capacity and vessel construction; they are designed for limescale control on high flow rate lines. Which solution is suitable is determined by the measured hardness value and the flow rate of the line.

The most practical question to ask when deciding is this: when hardness is measured at the outlet of the unit, does the value drop? A system that gives a measurable result is always more dependable than one that relies on a claim alone.

The System in Winter and During Long Periods of Non-Use

Because central systems can be installed outdoors, in a basement or in a cold space such as a shelter, winter conditions must be assessed separately.

• Risk of freezing: Filter housings, the tank and the valves crack when they freeze, and this damage usually cannot be repaired. If the system is in a place where there is a risk of freezing, insulation or heating measures must be taken.
• Long periods of non-use: In holiday homes or buildings left unused for a long time, stagnant water remains in the resin bed and in the filter housings. On return the system must be flushed several times, and the first water must not be used.
• Before shutting down: Running a regeneration before the softener is shut down leaves the resin standing in a freshly brined condition.
• Draining: If the risk of freezing is high, the system must be drained of water completely.

Short holidays need no special procedure; flow-controlled softeners do not regenerate, because there is no consumption.

Information to Prepare Before Asking for a Quote

Having the following information ready speeds up the process and lets you obtain an accurate, comparable quote:

• Water source: Mains, well or storage tank; if two are used together, which one and when.
• Water analysis: A current report if you have one; if not, a hardness measurement.
• Number of flats and users: The basis of total demand in building applications.
• Number of floors and booster pump situation: This sets the pressure profile.
• Tank volume: The tank capacity, if there is one, and the date it was last cleaned.
• Installation space: The space that can be set aside, the drain and the electricity situation.
• Priority: Limescale, sediment or odour — which problem is bothering you.

These seven headings will be asked whichever supplier you talk to. Preparing the answers in advance makes the quotes you receive comparable with one another and prevents a capacity unsuited to you being proposed in the first place.

What Does a Building Inlet System Add to the Service Charge?

In buildings where a central system is installed, new lines are added to the service charge. Knowing them in advance prevents arguments later.

• Cartridge consumables: Big Blue cartridges are renewed periodically according to the sediment load.
• Salt: If there is a softening stage, tablet salt is topped up regularly.
• Electricity: There is limited consumption for the automatic valves, the UV unit and the dosing pump if fitted.
• Regeneration water: A certain amount of water goes to drain for softening and for the backwash of the automatic filters.
• Scheduled service: The check and adjustment service carried out once or twice a year.

Against these items, what the building gains is a longer life for the heating equipment, fewer blockages in the plumbing and fewer faults in the appliances inside the flats. When deciding, it is sound to discuss both sides in figures; for that reason, when a system proposal is requested, the annual running cost should be asked for as part of the quote as well.

Filter Housing Sizes and Standard Cartridges

The housing size met most often in central systems is the Big Blue type. The advantage of these housings is the large surface area of the cartridge: at the same flow rate the pressure loss is lower and the cartridge can be used for longer.

What to watch when choosing a housing:

• Standard size: Cartridges in common sizes can be sourced from many suppliers; a non-standard cartridge size creates dependence later on.
• Port diameter: The inlet and outlet diameter must match the flow rate of the line; a narrow port creates pressure loss.
• Pressure rating: The pressure the housing can withstand must be above the working pressure of the line.
• Pressure gauge port: If the pressure can be read at the inlet and the outlet, blockage is noticed early.
• Spanner access: Clearance above and to the side is needed to remove the housing when changing the cartridge.

Does Central Treatment Replace a Drinking Water Purifier?

No, the two serve different purposes. A central system improves the water used throughout the property: it holds back sediment, removes chlorine, lowers hardness and protects the plumbing. It does not carry out the dissolved-solids separation that drinking water quality calls for.

The common and correct arrangement is this: a central system is installed for the building or the flat, and a separate reverse osmosis water purifier is used in the kitchen for drinking and cooking water. This arrangement has two benefits. First, the whole installation and the appliances are protected from limescale. Second, because the central system has taken out the sediment and the chlorine, the pre-filters of the kitchen unit last longer and the membrane is under less strain.

In regions where hardness is high, using these two systems together lowers the filter cost of the kitchen unit noticeably.

Buildings Supplied From Well Water

In buildings that use well water, central treatment comes close to being a necessity. Unlike mains water, well water carries a high load of sediment, turbidity and dissolved iron; microbiological risk must be assessed separately as well.

In such applications the chain gets longer: it starts with an automatic sand filter, an iron removal stage is added where needed, activated carbon and softening follow, and UV (ultraviolet) treatment is placed at the end. Because well water can change with the seasons, the analysis must be repeated periodically rather than once only.

Why Water Point Central Water Treatment Systems?

• Analysis-based engineering: The site survey is free of charge if the unit is purchased from us; the capacity and stage recommendation is shaped by the measurement results.
• Control valve: Clack valve products are among the components used.
• Standard-size cartridges: Cartridges in widely available standard sizes are used.
• Brand-independent technical service: Technical service is provided for units of all domestic and foreign brands.
• Continuity of spare parts: Filters, membranes, resin and salt are consumables; valves, pumps and tanks are durable spare parts.
• Units carry a 2-year warranty; misuse falls outside cover. Consumables such as filters, membranes and resin are outside cover.
• Certification: CE certification is held within the scope of the activities.

Installation and Technical Support

Water Point offers technical support covering site survey, engineering, installation, commissioning, scheduled maintenance and fault response. For industrial systems there is a service network across Türkiye; for domestic units service is provided in İstanbul and the surrounding provinces (such as Kocaeli and Tekirdağ). The service charge is set according to the work and the materials; no charge is made without the customer's approval.

Building Inlet Water Treatment Unit and Filter Prices

Flat and building inlet water treatment prices vary with the number of stages, the capacity, the housing type and the level of automation. The prices below are the current list prices on the relevant product pages. The table below lists the building inlet and flat inlet water treatment models with their stage structure and current prices. The difference between a building inlet water filter and a flat inlet water filter is the housing size and the flow rate; if limescale is the main problem, a building inlet water softener can be built into the same line.

Prices are for the standard configuration; they vary with capacity, the number of stages and the choice of automation. The right system is determined with measured hardness and real flow rate data.

For a system suited to your building or flat and a firm price, you can reach us on 0850 304 95 25 or at [email protected].

Let's determine the right system together

The site survey is free of charge if the unit is purchased from us; if only a survey and measurement are requested, a survey fee of 2,000 TL applies. Capacity and treatment stages are determined from the measurement results.