Specifications

2-51
JOHNSON CONTROLS
FORM 102.20-N1 (1109)
2
Flexible Connectors (VIFB Only)
Return steam condensate headers, hot water supply,
and return headers must be free to oat. A exible
connector MUST be installed as close as possible to
the coil to accommodate a minimum of 1/2” expansion
movement of the headers.
Failure to install connectors will restrict expansion
of the headers. This can result in bowing of tubes,
bending of ns, interference with damper operation, or
eventually tube breakage.
Freezing Conditions
Anti-stratication bafes are standard
on all IFB and VIFB coils mounted in
YORK Solution units.
The outside air and return air must be thoroughly
mixed before passing over the coil. When freezing air
enters only part of the coil, it creates a greater hazard
than when the airow entering the coil is of a uniform
temperature.
Coils used in series with respect to the airow must
have individual controls with ample space between the
coils for sensing devices, when required. Coils with
two or more rows are more sensitive to freezing than
single row coils.
On 100% outside air capable applications, locate low
limit at least 24" downstream of leaving edge of VIFB/
IFB casing. Low limit element must cross both face
and bypass areas, parallel to headers.
Shipping Bolts (VIFB Only)
Return steam condensate headers or hot water supply
and return headers are securely bolted to lower
mounting brackets to prevent damage to header and
tubes during shipment and piping of the coils. These
bolts MUST be removed before applying steam or hot
water but after all piping connections are made.
Piping Suggestions (VIFB and IFB)
See IOM Section 5, “Field Penetra-
tions for Piping and Electrical Con-
nections”.
Steam and hot water eld piping must be supported
separately after the exible connector to isolate piping
strains and additional expansion from the coils.
Internal steam manifolds and piping should be
insulated.
Steam traps should be sized for three times the
calculated condensate loading at the coil design
conditions, based on the pressure differential across
the trap, not the boiler pressure. Traps should be of
types that pass condensate and air at saturated steam
temperature. Inverted bucket traps should incorporate
thermostatic air vents.
Make return connection full size as required and
reduce only at trap. Do not use reducing bushing on
coil return connection.