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  • HEM SL Heat Exchange Module

    Compact Design & Flexible Configuration

    The compact design and flexible configuration of Powrmatic HEM SL gas fired heat exchange modules combine to provide designers with efficient and cost effective solutions for a wide variety of air heating and drying applications including new and re-furbished air handling units, duct heaters and dryers.

    HEM SL Heat Exchange Module - Compact Design & Flexible Configuration
  • HEM SL Heat Exchange Module

    Galvanised Casing & Stainless Tubes

    The Casing for the heat exchanger is formed from folded galvanised steel sheet to a rigid structure with inlet and outlet flanges for easy connection.A two pass (HEM-SL) and four pass (HEM-NVx) tubular assembly manufactured from aluminised steel formed, swaged and expanded without recourse to stress inducing welding. (AISI 409 grade stainless steel option available)

    HEM SL Heat Exchange Module - Galvanised Casing & Stainless Tubes
  • HEM SL Heat Exchange Module

    Burner Enclosure Option

    The Burner Enclosures are available for weatherproofed external ( as shown ) and internal plant room applications. Fully galvanized steel construction in either self finish or durable epoxy powder coated paint finish to BS 10-A-05 as standard Other colours are available priced upon application

    HEM SL Heat Exchange Module - Burner Enclosure Option
  • HEM SL Heat Exchange Module

    Stainless Steel Flue & Header

    All modules have AISI 409 grade stainless steel flue collector boxes complete with condensate drain point.

    HEM SL Heat Exchange Module - Stainless Steel Flue & Header
  • HEM SL Heat Exchange Module

    In Shot Matched Burners

    In-shot burners carefully matched to each tube assembly and manifolded to a common gas valve and multi-start ignition system, itself complete with flame monitoring and safety controls and supplied ready for use with natural gas (G20). Alternative LPG propane (G31) firing available to order.

    HEM SL Heat Exchange Module - In Shot Matched Burners
  • HEM SL Heat Exchange Module

    Electrical Enclosure

    In addition to the gas burner flame monitoring and safety controls all HEM modules are provided with a high temperature limit thermostat and flue fan proving device.

    HEM SL Heat Exchange Module - Electrical Enclosure
  • HEM SL Heat Exchange Module

    Bespoke & Custom Maufacturing

    Powrmatic have the in house capabilities of producing bespoke, non standard configured HEM modules. Pictured here is a 2 x HEM SL100 in series with rear air bypass section.

    HEM SL Heat Exchange Module - Bespoke & Custom Maufacturing

The HEM-SL range of heat exchange modules is based upon similar technology of our standard NVx range of suspended unit heaters.  HEM-SL units have been adapted to suit the needs of O.E.M’s by the provision of its slot-in casing arrangement. It has been specifically designed with Air Handling Manufactures in mind. It’s low resistance to airflow and ability to have combination units make it flexible for both selection and usage.

The HEM SL ranges from 30-200kW heat outputs, Where higher duties are required modules may be installed in either parallel or in series. Depending on model and size such multiple modules may be supplied factory pre-assembled. Fuel usage and emissions are a key consideration within the HEM design with all modules offering an efficiency of 90% at nominal airflow rates. Controllability is a key benefit of HEM modules. Each individual module can be specified in on/off, high/low or modulating burner format. High/low and modulating burners provide a turn-down ratio of between 2:1 and 4:1 depending upon model selection. The application of multiple modules further enhances the ability to increase turn-down rates and control heat output to close tolerance.

A feature of HEM tubular heat exchangers is their ability to provide efficient heat transfer with minimal pressure loss across the tube bank, thereby allowing designers to optimise fan selections. For applications with high airflows it is possible to provide bypass facilities. Typically modules are arranged for internal installation, often fitted within the confines of the air handling unit. External units can be supplied with fully weatherproofed burner enclosures. Room sealed enclosures are also available allowing the connection of ducted combustion air as well as access to the flue spigot. HEM SL modules are of similar configuration to NVx but are of two-pass design to minimise the majority of module widths to an impressive 400 mm.

Efficiency and ErP Compliance

From 1st January 2018 all warm air heaters used to provide comfort for the occupants of a heated space are required to meet minimum standards of ‘seasonal’ efficiency as determined by the Ecodesign regulation (EU) 2015/1188, Directive 2009/125/EC - Lot 21 Tier 1. Compliance to the standard is mandatory. HEM SL heaters placed on the market after 1st January 2018 comply with the requirements of the standard.

Features Include:

  • Wide range of outputs, featuring a multi-unit capability (individual units can be configured together to operate in series or parallel to provide higher outputs.
  • Slimline width - no requirement for inlet or outlet transition sections reducing material and labour costs for OEMs plus reduced length of the air handling unit.
  • Easy to service - multi-tube burners fed from a manifold with a single gas safety control.
  • Suitable for retro fit/upgrade - HEM-NVx is ideal for the conversion of hot water, steam or electric systems to gas.

HEM-NVx heaters are based on aluminised or T409 stainless steel tube heat exchange elements with each tube having a dedicated inshot type burner and a closed combustion circuit that is fan assisted with fully automatic controls. Units are available as on/off, high-low or fully modulating, with a low fire rate of 40%. Each unit is fitted with a condense drain and solenoid valve and supplied without controls housing for installation into air handling units.

Additonal Options

  • T316 stainless steel tube upgrade
  • High-low burner option
  • Modulating burner option
  • Burner enclosure - room sealed option
  • Burner enclosure - fully weatherproofed
  • Multi-stack unit option available
  • Air bypass facility available
  • Vertical or Horizontal flue assembly
  • 10kW to 200kW outputs

What do I do next?

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