14
Finned copper tube gas boilers & water heaters – Boiler manual
FTXLF-IOM-HN-1-110308 Copyright 2008 Mestek, Inc.
GenerAL pipinG reQUirements
Improper piping of this boiler/water heater will void
the manufacturer’s warranty and can cause boiler
failure resulting in flooding and extensive property
damage! Excessive water hardness causing scaling in
the copper heat exchanger tubes is NOT covered under
the manufacturer’s warranty. See Table 8, page 20.
Excessive pitting and erosion of the internal surface
of the copper heat exchanger tubes is NOT covered
under the manufacturer’s warranty if the result of high
water flow rates. See Table 7, page 16. Return water
temperatures below 140
o
F, 60
o
C will result in heat
exchanger damage from excessive condensation
voiding the manufacturer’s warranty, see Primary/
Secondary Piping. See Figure 9, page 15.
Shut off valves and unions should be installed at the inlet
and outlet connections of the boiler/hot water heater
to provide for isolation of the unit should servicing be
necessary.
Freeze protection
Installations in areas where the danger of freezing exists are not rec-
ommended unless proper freeze protection is provided. The follow-
ing precautions MUST be observed:
A continuous flow of water through the unit MUST be
1.
maintained! The pump responsible for flow through the
boiler/water heater must run continuously!
An ethylene glycol/water mixture suitable for the
2.
minimum temperature that the unit will be exposed to
must be used. The pump must be capable of producing
a minimum of 15% more flow and overcoming a
20% increase in head loss. Domestic water systems must be
isolated from the water heater by the use of a heat exchanger or
other approved method.
If the unit must be shut off for any reason the electric,
3.
gas and water supplies MUST be shut off and the unit
and its pump completely drained.
Improper outdoor installation of this unit can cause
boiler failure voiding the manufacturer’s warranty!
relief valve
Pipe the discharge of the pressure relief valve as shown in Figure 9,
page 15.
Never install any type of valve between the boiler/
water heater and the relief valve or an explosion causing
extensive property damage, severe personal injury or
death may occur!
Flow switch
The flow switch supplied with the boiler/water heater must be wired
to the terminal strip in the control panel to prevent the boiler from
firing unless there’s adequate water flow through the unit. The flow
switch must be installed in the supply piping adjacent to the boiler
outlet connection.
Failure to properly install the flow switch may result
in damage to the boiler/water heater heat exchanger
voiding the warranty!
HeAtinG system pipinG
General piping requirements
All heating system piping must be installed by a qualified technician
in accordance with the latest revision of the ANSI/ASME Boiler
and Pressure Vessel Code, Section IV, and ANSI/ASME CSD-1,
Standard for Controls and Safety Devices for Automatically Fired
Boilers. All applicable local codes and ordinances must also be fol-
lowed. A minimum clearance of 1 inch, 25 mm must be maintained
between heating system pipes and all combustible construction. All
heating system piping must be supported by suitable hang-
ers not the boiler. The thermal expansion of the sys-
tem must be considered when supporting the system. A
minimum system pressure of 12 psig, 82.7 kPa must
be maintained.
Heating boiler piping connections
The supply and return connections should be sized to suit the system,
per Table 6.
Supply & Return Pipe Sizing
table 6
Input
MBH
Supply
size
Return
size
3000
4" FLANGE
4" FLANGE
4000
4" FLANGE
4" FLANGE
