Instantaneous Water Heater; Condensing Heat Recovery Module (Chrm) - Camus Hydronics MFH060 Installation, Operation And Service Manual

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INSTANTANEOUS WATER HEATER

An instantaneous water heater is designed to deliver hot water without the use of a storage tank. It is
suitable for applications with variable load such as restaurants, condominiums, apartments and motels.
(See Figure 7) Call factory for recommendations.
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CONDENSING HEAT RECOVERY MODULE (CHRM)

The MicoFlame All Stainless Steel CHRM is mounted in a stainless steel chamber at the rear of the
appliance. The CHRM is constructed from all stainless steel headers and special multiple horizontal
stainless tubes. This CHRM is designed to maximize heat transfer efficiency by fully condensing flue
products and is suitable to resist the low pH of condensate.
The CHRM must be supplied with adequate water flow at all times during operation. Do not operate the
appliance with the CHRM piped out or isolated.
The CHRM is mounted in the discharge of the flue products from the primary heat exchanger. This allows
additional heat to be absorbed from the flue products exhausted from the combustion process. If isolation
valves are provided on the CHRM, the provision of a relief valve at the outlet of the CHRM is
recommended. This valve is to be sized at minimum for 10% of the input of the appliance and is to be
piped to drain.
When cold water supply with temperatures less than 130ºF (55ºC) passes through the CHRM it will cool
the flue products below dew point resulting in the formation of condensation. Furthermore, the volumetric
flow rate of the flue gases will be reduced.
The appliance CHRM loop may be used in condensing mode for a variety of application including
domestic hot water and hydronic space heating. Recommended piping arrangement is shown in Figure 8.
Maximum capacity through the CHRM is summarized in Table 6; flows in excess of 60 GPM must be
bypassed.
Figure 7: Instantaneous Water Heater Suggested Piping
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