Control House, Inc. Manufacturer Representatives for Instrumentation and Control
Bacharach manufactures gas detection products and systems for commercial applications, such as boiler and chiller rooms, cold storage areas, ice arenas, parking and maintenance garages, mechanical rooms, research facilities and wineries.
The Multi-point/Multi-gas HGM MZ refrigerant monitor and the companion HGM RD remote display module are a good choice for monitoring chillers and storage areas. This combination provides low level continuous monitoring of CFC, HCFC and HFC and Halon refrigerant gases for early detection of refrigerant gas leakage. It has proven to be a reliable and low maintenance combination, and it has been the choice for many companies in this area. There is also a single zone version of it called the HGMSZ refrigerant leakage monitor, and it can also be set for the selected refrigerant in the field.
Two types of ammonia refrigerant gas leakage monitoring systems are now available. The first is similar to the refrigerant monitors described previously and have the identities AGM MZ / AGM RD and AGM SZ. These units draw samples and measure them using an infrared sensor. The second type uses dispersed sensors located in the areas to be monitored, and are wired to a central monitoring system. These are identified as the GTX150 and GTX350 sensors, and GDA400 and GDA1600 controllers.
The GDC150 and GDC350 are gas sensor monitors can detect a wide range of gases including CO, O2, H2S, LEL, NO, NO2, NH3, SO2, refrigerants and total volatile organic compounds. Their sensors include electro-chemical, solid state and photo-ionization detectors. The GDC350 includes proprietary calibration algorithms to extend the amount of time between calibrations, and one or two sensors.

Control House is the exclusive representative for these products in Minnesota, Wisconsin, North Dakota and South Dakota, starting in 1995.

Your contacts at Control House are:
Pat McClernon 952-746-3485

Doug Andersen 952-746-3484
If you need additional technical information, you may also visit and select Analyzers and Monitors for a complete listing of technical data files and manuals.

For detailed information, here are the spec sheet and manual links:
GDA-400 Four Channel Gas Alarm Controller for Ammonia267.07 KB
GDX-350 Low Temperature Ammonia Gas Transmitter408.5 KB
GDX 150 Ammonia Gas Transmitter270.33 KB
GDC-350 Electro-Chemical, Solid State, or PID Gas Transmitter363.76 KB
GDC-150 Electro-Chemical, Solid State, or PID Gas Transmitter364.25 KB
GDA-1600 Sixteen Channel Gas Alarm Controller for Ammonia280.31 KB
HGM SZ Refrigerant & AGM SZ Ammonia Single Zone Sample Draw Monitors5.54 MB
HGM MZ Multi-zone Refrigerant Monitors Datasheet.pdf397.93 KB
HGM-RD Remote Display Instruction Manual1.11 MB
BACnet Option for HGM-MZ.pdf2.3 MB
HGM300-RDM800-mini manual.pdf1.63 MB
H-SEM Halogen Safe Entry Monitor1.38 MB
H25-IR Industrial Refrigerant Leak Detector3.71 MB
MGD-100 Gas Detection System1.14 MB
MGS-150 Gas Transmitter Series1.13 MB
PAGM Portable Area Gas Monitor for finding leaks771.44 KB