Service manual

11
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 5. Maximum capacity through
the CHRM is summarized in Table 6; flows in
excess of 60 GPM must be bypassed.
Figure 5: Typical Condensing System
Condensate from the MicoFlame Grande must
be treated before being discharged to drain. pH
level of the condensate is to be checked
regularly and the neutralizing medium is to be
replaced as required. A neutralizing cartridge is
available from the factory. The condensing
MicoFlame Grande must be vented using only
special venting type AL29-4C stainless steel or
equivalent, please follow instructions detailed
below.
When supplied with the CHRM, the MicoFlame
Grande is 95% efficient (category II or IV
appliance) which requires the use of a special
venting system fabricated from AL29-4C or
equivalent material. Only venting components
listed by a nationally recognized testing agency
may be used.
This appliance may be installed with
conventional, sidewall or vertical venting.
Conventional vented appliances operate with
negative pressure in the vent pipe and require a
special vent adapter to increase the flue outlet
diameter. Sidewall and vertically vented
appliances operate with positive pressure in the
vent pipe and may be directly connected to the
flue outlet without the use of an increaser.
Consult the vent pipe manufacturer’s
instructions for minimum clearances to
combustible material for vent components. In the
absence of instructions, the minimum clearance
to combustible material is six inches.
Consult vent pipe manufacturer’s instructions for
proper method of sealing vent pipe sections and
fittings. In the absence of instructions, make
sure that pipe and fittings are clean by swabbing
with alcohol. Use Dow Corning 736 or 732 RTV,
Polybar # 500 RTV or Sil-bond 4500 or 6500 to
seal vent pipe. Do not use other sealants or
adhesives except as expressly permitted by vent
manufacturer’s instructions.
Consult vent pipe manufacturer’s instructions for
vent system assembly. Follow vent pipe
manufacturer’s instructions if those instructions
differ from this section.
Figure 6: Secondary Heat Exchanger
Table 7 – CHRM Head Loss & Flow
Model US GPM ∆P - Ft.
2010 40.0 5.5
2500 50.0 8.0
3000 60.0 11.0
3500 40.0 5.5
4000 40.0 5.5
7.9 PIPING
The boiler can be piped in parallel or in
primary/secondary to the system. The type of
piping chosen affects the location of the control’s
operating temperature sensor. The control can
either use the boiler outlet sensor or the boiler
system sensor.