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MTA

DHW

The MTA DHW is an indirect single plate heat interface unit designed to provide either instantaneous domestic hot water (DHW) in an apartment, detached property, office building or similar when connected to a central energy source within a heat network. The production of instantaneous DHW minimises the risk of legionella bacteria multiplying since no hot water is stored. There are two models available, the MTA Eco DHW and the MTA Plus DHW.

35kW

  • SWEP AS 316 heat exchanger (MTA Eco)

  • SWEP LAS AISI 316 heat exchanger (MTA Plus)

  • Ultra-compact dimensions

  • Fully electronic unit

  • Keep warm function (On/Off/Timed)

  • 10 bar rated

  • Unique HydraBlok® back plate

  • Primary flow rate limitation

  • Advanced diagnostics

  • Remote connectivity

  • First fix kit supplied as standard

  • Servicing and parts replacement from front

  • Isolation & drain valves fitted as standard

  • Labelled water connections

  • Closed-cell foam insulation cover

  • Optional flushing bypass valve available

  • Optional top entry pipe kits available

*Subject to Terms & Conditions

Downloads

Brochure

Installation Guides

BIM Drawings

Download
User Guide
MTA Installation Guide
Flushing Bypass Installation Guide
Download
Features in detail
Unique HydraBlok® back plate

Most other heat interface units available on the market are often a myriad of metal pipework and brass fittings. With this type of HIU every union is a potential source of a water leak, as the unions often loosen during transportation from the factory to the point of use. The MTA has little potential for leaks as it is not fitted with metal pipework and brass fittings. Everything is built upon a unique HydraBlok® backplate which contains all waterway channels moulded within a composite chassis.

Return temperature limitation

To ensure the heat network operates at maximum efficiency, the MTA will modulate the rate of water flow provided by the internal apartment heating circuit pump to match the heat load of the apartment at any one time. This maintains the designed heating circuit ΔT and limits the temperature of the water returning to the primary circuit.

Primary flow rate limitation

The MTA can limit the primary flow rate in both DHW and heating mode, independently of each other.  Limiting the maximum flow rate that the HIU can take from the primary system, during space heating production, guarantees the design flow rate used to calculate system demand, is not exceeded.

Advanced pump control

The MTA features 24 hour pump exercising - if the heating circuit has not been used for 24 hours, the MTA will run the pump (and open the heating regulation valve) for 10 seconds, ensuring debris cannot build up in the pump bearings. The MTA also features a low pressure cut out. If the heating circuit pressure falls below 0.4bar, the pump will stop running. The unit will continue to produce DHW.

Advanced diagnostics

The control panel within the MTA provides a friendly, intuitive user experience. In addition, it provides an extremely high level of real time data, offering an overview of the current conditions within the network, HIU and apartment.

1
Primary flow temperature
2
DHW temperature
3
MCW temperature
4
Primary return temperature
5
District modulating valve stepper motor position (0 to 250)
6
DHW flow rate
7
DHW regulation valve stepper motor position (0 or 250)
8
Heating regulation valve stepper motor position (0 or 250)
13
Primary flow rate
1
Primary flow temperature
2
DHW temperature
3
MCW temperature
4
Primary return temperature
5
District modulating valve stepper motor position (0 to 250)
6
DHW flow rate
7
DHW regulation valve stepper motor position (0 or 250)
8
Heating regulation valve stepper motor position (0 or 250)
13
Primary flow rate
ModuHub (optional extra)

ModuHub enables remote monitoring and control of the MTA heat interface unit, enabling network operators to continuously optimise their heat networks, ensuring reduced running costs whilst improving service quality for the end users.
It can also be used to detect and alert maintenance providers to possible faults, allowing faults to be resolved remotely and considerably reducing the number of planned service/maintenance visits to site.
ModuHub creates an open protocol wireless billing network, removing the requirement for an Mbus network. Through our open API, meter reads can be retrieved by billing providers using LoRa Communication. Moduhub can be utilised for both prepayment or credit billing.
The ModuHub box is small and compact, allowing it to fit within the MTA casing.

Features in detail
35kW
Unique HydraBlok® back plate

Most other heat interface units available on the market are often a myriad of metal pipework and brass fittings. With this type of HIU every union is a potential source of a water leak, as the unions often loosen during transportation from the factory to the point of use. The MTA has little potential for leaks as it is not fitted with metal pipework and brass fittings. Everything is built upon a unique HydraBlok® backplate which contains all waterway channels moulded within a composite chassis.

Return temperature limitation

To ensure the heat network operates at maximum efficiency, the MTA will modulate the rate of water flow provided by the internal apartment heating circuit pump to match the heat load of the apartment at any one time. This maintains the designed heating circuit ΔT and limits the temperature of the water returning to the primary circuit.

Primary flow rate limitation

The MTA can limit the primary flow rate in both DHW and heating mode, independently of each other.  Limiting the maximum flow rate that the HIU can take from the primary system, during space heating production, guarantees the design flow rate used to calculate system demand, is not exceeded.

Advanced pump control

The MTA features 24 hour pump exercising - if the heating circuit has not been used for 24 hours, the MTA will run the pump (and open the heating regulation valve) for 10 seconds, ensuring debris cannot build up in the pump bearings. The MTA also features a low pressure cut out. If the heating circuit pressure falls below 0.4bar, the pump will stop running. The unit will continue to produce DHW.

Advanced diagnostics

The control panel within the MTA provides a friendly, intuitive user experience. In addition, it provides an extremely high level of real time data, offering an overview of the current conditions within the network, HIU and apartment.

1
Primary flow temperature
2
DHW temperature
3
MCW temperature
4
Primary return temperature
5
District modulating valve stepper motor position (0 to 250)
6
DHW flow rate
7
DHW regulation valve stepper motor position (0 or 250)
8
Heating regulation valve stepper motor position (0 or 250)
13
Primary flow rate
ModuHub (optional extra)

ModuHub enables remote monitoring and control of the MTA heat interface unit, enabling network operators to continuously optimise their heat networks, ensuring reduced running costs whilst improving service quality for the end users.
It can also be used to detect and alert maintenance providers to possible faults, allowing faults to be resolved remotely and considerably reducing the number of planned service/maintenance visits to site.
ModuHub creates an open protocol wireless billing network, removing the requirement for an Mbus network. Through our open API, meter reads can be retrieved by billing providers using LoRa Communication. Moduhub can be utilised for both prepayment or credit billing.
The ModuHub box is small and compact, allowing it to fit within the MTA casing.

Specification
35kW
Primary Circuit (district)
Max operating pressurebar10
Maximum supply temperature°C85
Min/max differential pressurebar0.5/4
Domestic Hot Water (apartment)
Maximum heat exchanger capacity (Eco/Plus)kW90 / 107
Hot water set-point°C40-60
Maximum cold feed supply pressure bar10
General
Dimensions (HxWxD)mm600 x 500 x 312
Water connectionsmm18/22
Weight (HIU)kg21
Weight (first fix kit)kg4
Electrical
Mains supply230-1-50
Power consumptionW85
ProtectionIP44
Connections
District inletBSPG 3⁄4"
District returnBSPG 3⁄4"
Domestic hot water outletBSPG 3⁄4"
Mains cold water inletBSPG 3⁄4"
Domestic cold water outletBSPG 3⁄4"
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