Installation / Operation Instruction Manual
Page 15
Brute Mini
SECTION 5.
Water Connections
5A. Water Piping
Figure 10. shows ‘typical’ plumbing installations. Be
sure to provide unions and isolation valves at the
boiler inlet and outlet so it can be isolated for service.
Check local codes for specic plumbing requirements
before beginning the installation.
An ASME pressure relief valve is supplied on all
BJVS boilers, and is pre-set at 30 PSI. The valve
outlet piping must discharge to a drain. Under no
circumstances should the relief valve piping be a
closed circuit.
A pressure reducing valve (automatic feed) must be
used to maintain the system at constant proper pressure
(see Figure 10). Supply properly installed purge
valves to eliminate air from each circuit.
A drain valve is supplied with the boiler, and can be
found in the plastic bag shipped with each boiler. This
valve is to be installed on the lower right side of the
boiler and is used for draining the unit. To drain the
boiler completely, open the drain valve and remove
the two drain plugs located on the lower left side of
the boiler.
Be sure to include air vent devices located at the
highest point in the system to eliminate trapped air,
and an air elimination device near the outlet side of the
BJVSboiler. Manual vent valves are recommended.
Hot water piping should be supported by suitable
hangers or oor stands, NOT by the boiler. Due
to expansion and contraction of copper pipe,
consideration should be given to the type of hangers
used. Rigid hangers could transmit noise through the
system caused by the piping sliding in the hangers.
It is recommended that padding be used when rigid
hangers are installed.
Gas piping should also be supported by suitable
hangers or oor stands, not the boiler.
A properly sized expansion tank must be included in
the system.
5B By-pass Piping
The following information and suggestions are made
on by-pass piping as it affects the temperature rise at
the boiler. A boiler temperature rise must be taken on
all BJVS boiler installations. If the temperature rise
exceeds 30°F (17°C) at full rate, it is an indication that
the boiler is not receiving adequate water ow. Check
the pump for any obstruction, replace the pump with a
larger size where necessary, or install a system by-pass
as indicated in Figures 10 and 11.
A full sized, 1¼" bypass with balancing valves is
strongly recommended for all systems, and required
when: 1) the boiler is installed without primary-
secondary piping in a multiple zone system; 2) when
the return water temperature can be expected to be
lower than 120°F (44°C); or 3) whenever the system
piping on the outlet side of the boiler may allow
reduced ow through the heat exchanger, causing
excessive temperature rise (see Section 5.2).
Note: Bradford White strongly recommends a primary/
secondary piping system for all installations, especially
sizes 125, 160 and 225. In this system, a circulator is
dedicated to pumping the boiler only. This circulator
should be sized for the boiler head loss and ow rate.
All precautions must be taken by the installer to insure
that a maximum temperature rise through the boiler
does not exceed 30°F (17°C). The temperature rise
on boilers installed in multi-zone systems using zone
valves must be taken when the zone of the longest
length and/or the zone of the highest head loss is open.
A full size, 1¼" diameter by-pass with
balancing valve must be installed if a return water
temperature below 120°F (44°C) is expected under
operating conditions regardless of boiler size. This
may be expected in many systems, including in-
oor radiant and snow melt systems.
Table 7. Temperature Rise °F °C.
gpm = Water Flow in gallons per minute. l/s = Water ow in liters per second.
ft = Pressure drop (headloss) through the boiler in feet of water. m = Pressure drop (headloss) through the boiler in meters of water.
Notes: 1. Shaded area is the recommended ow and temperature rise.
2. Temperature rise and associated ow rates are based on high re operation at the Normal Input Rate from the rating plate.
15°F 8°C 20°F 11°C 25°F 14°C
Size Flow Rate Headloss Flow Rate Headloss Flow Rate Headloss
gpm l/s ft m gpm l/s ft m gpm l/s ft m
50 5.3 0.3 0.3 0.1 4 0.3 0.2 0.1 3.2 0.2 0.1 0
75 8 0.5 0.6 0.2 6 0.4 0.3 0.1 4.8 0.3 0.2 0.1
100 10.7 0.7 1.3 0.4 8 0.5 0.7 0.2 6.4 0.4 0.5 0.2
125 13.3 0.8 2.2 0.7 10 0.6 1.3 0.4 8 0.5 0.8 0.2
160 17 1.1 2.5 0.8 12.8 0.8 1.8 0.5 10.2 0.6 1.2 0.4
225 24 1.5 5 1.5 18 1.1 3.1 0.9 14.4 0.9 1.9 0.6