ATSx Hot Water Tanks
Adveco ATSx stainless steel hot water tanks offer a range of models from 200 to 1000 litres at 10 bar as standard. This range of stainless steel vessels is suitable for use as hot water buffers, and single, or dual coil calorifiers as required for the application.
- Corrosion-resistant stainless steel construction
- Vessels from 200 to 1,000 litres
- Rated 10 bar as standard
- Storage tank, single coil, and twin coil options
Features & Key Technologies
- Vessels rated up to 1000 litres
- 10 bar as standard
- Single coil, twin coil and plate heat exchanger
- Multiple connection points
- Corrosion resistant stainless steel construction
- Ideal for high pressure applications such as tall buildings with basement plant
ATSx Hot Water Tanks Options
The range has five configurations, differentiated by the number of internal heat exchange coils included as standard.
ATSB is a range of high-quality buffer vessels supplied without any internal heat coils, with multiple connection points and a clean-out access flange. As a buffer vessel only, ATSB can be used to expand the dump load capacity of a water heating installation.
ATSI, ATST, ATSH and ATSR water heaters are designed for use with indirect heat sources as calorifiers, across DHW installations with smaller demands that need more than six bar pressure.
- ATSI has a single internal fixed heating coil at low level.
- ATST has two internal fixed heating coils, at low and high level.
- ATSH has a single internal high capacity fixed heating coil at low level, for use with a high powered indirect heat source.
- ATSR has two internal fixed heating coils with increased surface area, designed for use with renewable heat sources, at low and high level.
All models feature multiple connection points and a clean-out access flange.
The ATSx range is built from corrosion-resistant AISI 316Ti and 316L stainless steel, making it a strong choice for soft water areas in the UK.
For hard water areas where scale build-up can be a problem, Adveco can specify 9kW and 12kW electric immersions with a uniquely low 6W/cm² heat intensity. This slows the potential for scale build-up without any drop in hot water output, making ATSx a resilient option whether the water is naturally hard or soft.
What is a high pressure commercial hot water tank?
Most commercial hot water tanks are rated to a standard 6 bar working pressure, which is enough for the majority of buildings. A high pressure tank is built to withstand more than that, needed wherever the system pressure, often from static head in a tall building with plant several floors below street level, would exceed what a standard tank can safely handle. ATSx is Adveco’s high pressure range, rated to 10 bar as standard, built in stainless steel for corrosion resistance at that pressure.
The problem ATSx solves
Basement plant rooms in tall buildings run into a problem that catches specifiers out: the water pressure at the bottom of a 10 or 15-storey building, from static head alone, can exceed what a standard 6 bar cylinder is rated for, before you even add the working pressure of the system itself. Specify a standard vessel without checking, and it either fails prematurely or fails a commissioning check, and either way you’re now sourcing a replacement under time pressure on an occupied or nearly-complete building.
ATSx removes that risk by being rated to 10 bar as standard, not as a costly bespoke option. It’s built to be the straightforward, off-the-shelf answer for exactly the buildings where a standard tank isn’t good enough, high rise offices, hotels, and healthcare buildings with basement or below-ground plant, without the lead time and expense of getting something custom-made.
Ancillaries and Related System Components
A handful of components complete an ATSx installation, all available from Adveco alongside the tank itself:
sets and holds the storage temperature, with a 0-95°C range covering standard Legionella-safe storage through to higher process temperatures.
a safety cut-out that protects the system if the control thermostat fails or the water temperature runs higher than it should.
houses the thermostat sensor in the vessel wall, allowing it to be removed or replaced without draining the tank.
circulates water within the tank to even out temperature layering, useful where a single fixed sensor point wouldn’t otherwise reflect the true stored temperature.
contact Adveco for options and details specific to your installation.
Where ATSx fits
ATSx exists to solve a specific problem: standard calorifiers are typically rated to 6 bar, which isn’t enough for taller commercial buildings where basement plant rooms have to push water up through several floors of static head pressure. Rated to 10 bar as standard, ATSx is built for exactly that scenario: tall buildings, multi-storey developments, and any site where standard pressure ratings fall short, without needing a bespoke tank specified from scratch.
Because the range is built from AISI 316Ti and 316L stainless steel, it holds up well against both hard and soft water conditions found across the UK, and the option to specify low heat intensity immersions (9kW and 12kW at 6W/cm²) gives extra protection against scale in harder water regions without compromising output.
The five configurations, ATSB, ATSI, ATST, ATSH and ATSR, cover everything from a straightforward buffer vessel through to twin coil renewable-ready calorifiers, so the same core product can be specified across gas, electric, heat pump, or mixed heat source systems. ATSx is commonly specified in high rise offices, hotels, and healthcare buildings where basement or below-ground plant rooms are standard, and where reliability under pressure matters as much as thermal performance.
Why stainless steel over carbon steel for high pressure DHW
High pressure DHW installations put more strain on a vessel than a standard 6 bar system, which makes material choice more consequential, not less.
Carbon steel vessels need a protective lining, usually enamel or glass, to stop the water corroding the tank from the inside. That lining is a wear surface: at higher pressures and with the added mechanical stress of a taller water column above the vessel, any weak point in the lining becomes a bigger risk over the vessel’s working life. Stainless steel doesn’t rely on a lining at all. AISI 316Ti and 316L resist corrosion at the metal itself, so there’s no coating to fail, chip, or wear thin over years of pressure cycling.
That’s a large part of why ATSx is built in stainless steel rather than carbon steel with a heavier-duty lining: at 10 bar as standard, in installations where a leak means shutting down plant several floors below the point of failure, removing the lining as a point of failure is exactly the reliability those installations need.
Technical Specifications & Downloads
Literature
Specifications
Model |
Storage Capacity [l] |
Tank Inlet and Outlet Connection Sizes [in] |
Vessel Dimensions incl. Insulation (OD x H) [mm] |
Heating Coil Capacities* [kW] |
Standing Losses [W] |
Energy Efficiency Class |
ATSB 200 ATSI 200 ATSH 200 |
212 212 212 |
1.25 0.75 0.75 |
700 x 1485 700 x 1480 700 x 1490 |
n/a 19.1 38.3 |
53 52 58 |
B B B |
ATSB 300 ATSI 300 ATST 300 ATSH 300 ATSR 300 |
289 289 289 289 289 |
1.25 1.00 1.00 1.00 1.25 |
700 x 1735 700 x 1740 700 x 1740 700 x 1740 700 x 1740 |
n/a 29.7 17.0 + 29.7 55.3 37.0 + 29.0 |
65 63 66 66 66 |
B B B B B |
ATSB 400 ATSI 400 ATST 400 ATSH 400 ATSR 400 |
411 411 411 411 411 |
1.50 1.00 1.00 1.50 1.50 |
800 x 1725 800 x 1735 800 x 1735 800 x 1735 750 x 1975 |
n/a 36.1 19.1 + 36.1 80.8 39.0 + 35.0 |
75 72 76 85 85 |
B B B C C |
ATSB 500 ATSI 500 ATST 500 ATSH 500 ATSR 500 |
490 490 490 490 490 |
1.50 1.00 1.00 1.50 1.50 |
800 x 1975 800 x 1990 800 x 1990 800 x 1985 800 x 1985 |
n/a 36.1 19.1 + 36.1 85.1 42.0 + 53.0 |
83 79 83 98 98 |
B B B C C |
ATSB 580 ATSI 580 ATST 580 |
575 575 575 |
1.50 1.50 1.00 |
850 x 1985 850 x 1990 800 x 1990 |
n/a 38.3 19.1 + 38.3 |
106 102 105 |
C C C |
ATSB 750 ATSI 750 ATST 750 ATSH 750 ATSR 750 |
756 756 756 756 756 |
2.00 1.50 1.50 2.00 1.50 |
950 x 2055 950 x 2080 950 x 2080 950 x 2075 950 x 2080 |
n/a 51.0 29.7 + 51.0 106.4 66.0 + 65.0 |
120 116 120 120 120 |
C C C C C |
ATSB 1000 ATSI 1000 ATST 1000 ATSH 1000 ATSR 1000 |
990 990 990 990 990 |
2.00 2.00 2.00 2.00 2.00 |
1950 x 2045 1050 x 2080 1050 x 2080 1050 x 2075 1050 x 2090 |
n/a 51.0 38.3 + 59.0 149.8 74.0 + 77.0 |
140 135 140 140 140 |
C C C C C |
* ATSB, ATSI, ATST, ATSH coil heating capacities based on 80/60:10/60 primary/secondary flow temperatures. ATSR coil heating capacities based on 80/45 primary (upper coil) and 55/45 primary (lower coil) temperatures for renewable heat sources.
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Frequently Asked Questions
A tank built to handle more than the standard 6 bar working pressure, needed where system pressure, often from static head in a tall building, exceeds what a standard tank is rated for. ATSx is rated to 10 bar as standard.
Yes. Standard AISI 316Ti/316L stainless steel already resists scale better than carbon steel, and for hard water regions we can specify 9kW or 12kW electric immersions with a low 6W/cm² heat intensity, which slows scale build-up further without reducing hot water output.
ATSB is a buffer vessel with no internal coil. ATSI has a single fixed coil at low level. ATST has two coils, low and high level. ATSH has a single high-capacity coil for a high-powered indirect heat source. ATSR has two coils with increased surface area, designed for renewable heat sources such as heat pumps.
10 bar as standard makes ATSx suitable for higher pressure applications, such as tall buildings with basement plant rooms, where standard 6 bar vessels aren’t rated for the system pressure.
ATSx suits any project where plant room pressure exceeds standard ratings, most commonly high rise offices, hotels, and multi-storey developments with basement or below-ground plant rooms.
Yes, via the ATSR configuration. Its twin coils have increased surface area specifically designed for renewable heat sources including heat pumps, where lower flow temperatures need more heat exchange area to deliver the same output.
Carbon steel vessels need a protective lining that can wear or fail over time, a bigger risk at high pressure. Stainless steel resists corrosion at the metal itself, with no lining to fail, which is why ATSx is built in AISI 316Ti and 316L for high pressure DHW installations.
The rule of thumb is static head: roughly every 10 metres of height above the plant room adds about 1 bar of pressure. If your plant room sits several floors below the highest point the water needs to reach, it’s worth checking that figure against a standard 6 bar rating before you specify. If you’re not sure, tell us the building height and plant room location and we’ll confirm what rating you need.
It’s installed the same way as Adveco’s other stainless steel calorifiers, standard commercial plumbing and commissioning practice, no special tooling required. Adveco’s commissioning service is available if you’d rather have that handled directly.
The same as any indirect calorifier: periodic inspection through the clean-out access flange, and checking connections and any fitted immersions. High pressure doesn’t mean higher maintenance, it just means the vessel itself is rated for it.
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