Burnham 8HE Series Installation, Operating And Service Instructions page 18

3
Water Trim and Piping
Figure 3-2: Safety Relief Valve Installation
D. Install Drain Valve in rear of Left End Section,
Tapping "G". See Figure 3-3. Components are
located in Water Trim Carton.
E. Install Temperature-Pressure Gauge. Components
are located in Water Trim Carton.
1. Standard Temperature - Pressure Gauge
Piping. See Figure 3-4.
a. Install 2 in. NPT x 10 in. lg. nipple with
gauge tapping into Supply Tapping "A".
See Figure 2-3. Gauge tapping should face
forward.
b. Insert Temperature-Pressure Gauge.
Tighten by applying pressure to square
shank on back of gauge. DO NOT APPLY
PRESSURE ON GAUGE CASE since this
may ruin gauge calibration.
2. Alternate Temperature-Pressure Gauge Piping.
See Figure 3-5.
a. Install 2 NPT x 10 in. Nipple into Supply
Tapping "A". See Figure 2-3.
b. Install 2 NPT x ¾ NPT x 2 NPT Tee
(provided) or 2 NPT x 2 NPT x ¾ NPT Tee
(installer furnished). ¾ NPT leg should face
forward.
c. Install ¾ NPT x ¼ NPT Bushing.
d. Insert Temperature-Pressure Gauge.
Tighten by applying pressure to square
shank on back of gauge. DO NOT APPLY
PRESSURE ON GAUGE CASE since this
may ruin gauge calibration.
18
(continued)
8HE Installation, Operating & Service Instructions
Figure 3-3: Drain Piping Installation
!
WARNING
• Burnham Commercial recommends maintaining
temperature differential (drop) across the system
at 40°F or less and return water temperature at
minimum of 135°F.
• Continued boiler operation for prolonged periods of
time under conditions when temperature differential
across the system exceeds 40°F and/or return water
temperature stays below 135°F, may result in premature
boiler failure due to flue gas condensation and/or
thermal shock.
F. Connect system supply and return piping to
boiler.
1. Maintain minimum ½ in. clearance from hot
water piping to combustible materials.
2. Pump flow rates and minimum boiler supply
and return pipe sizes are shown in Table 3-1.
3. If boiler is used in connection with refrigeration
systems, boiler must be installed with chilled
medium piped in parallel with heating boiler
using appropriate valves to prevent chilled
medium from entering boiler. See Figure 3-6.
4. If boiler is connected to heating coils located
in air handling units where they may be
exposed to refrigerated air, boiler piping
must be equipped with flow control valves
to prevent gravity circulation of boiler water
during cooling system operation. A hot water
boiler installed above radiation level must be
provided with a low water cutoff device as part
of installation. The HydroStat control provided
with the boiler includes a low water cut-off
function.
5. Continued boiler operation for prolonged
periods of time under conditions when
temperature differential across the system
exceeds 40°F and/or return water temperature
stays below 135°F, may result in premature
boiler failure due to flue gas condensation and/
or thermal shock.
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