LAARS Mini-Therm JVS (Sizes 50-225) - Install and Operating Manual - Manual (Page 15)

Mini-Therm JV Page 15
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 specific plumbing requirements
before beginning the installation.
An ASME pressure relief valve is supplied on
all JV 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
JV boiler. Manual vent valves are recommended.
Hot water piping should be supported by suitable
hangers or floor 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 floor stands, not the boiler.
A properly sized expansion tank must be included in
the system.
4. A sediment trap (drip leg) must be installed
ahead of the gas controls (see Figure 8). Fit the
trap with a threaded cap which can be removed
for cleaning.
5. Install a manual gas shutoff valve for service and
safety. Do not use a restrictive gas cock. Flexible
gas connectors, if used, must be CSA rated for
the total input rating of the boiler.
6. Disconnect the boiler and its individual shutoff
valve from the gas supply system during pressure
testing of the system at pressures higher than 1/2
pounds per square inch (psi) (3.45 kilopascals
[kPa]). If the test pressure is equal to or less than
1/2 psi (3.45 kPa), close the manual shutoff valve
on the heater during the piping pressure test.
7. If the gas supply pressure is less than required,
check for undersized pipe between the meter and
the boiler, a restrictive fitting, or an undersized
gas meter. Gas supply pressures to the heater are
listed in Table 5.
NOTE: The maximum inlet gas pressure must not
exceed the specified value. The minimum value listed is
for the purpose of input adjustment. Refer to Table 5.
NOTE: The boiler and all other gas appliances
sharing the boiler gas supply line must be firing
at maximum capacity to properly measure the
inlet supply pressure. Low gas pressure could be
an indication of an undersize gas meter and/or
obstructed gas supply line.
8. The correct high fire burner manifold gas
pressure is stamped on the rating plate. The
regulator is pre-set at the factory, and normally
requires no further adjustment. For two-stage
units (JVS 100-225) be sure unit is able to fire at
both high and low fire.
9. Before operating the boiler, the complete gas
supply system and all connections must be tested
for leaks using a leak detector solution. Do not
use an open flame.
Caution
Some leak test solutions (including soap and
water) may cause corrosion or stress cracking.
Rinse the piping with water after testing.
Attention
Certaines solultions d’essai d’étanchéité (y
compris l’eau et le savon) peuvent causer de
la corrosion ou de la fissuration. Rincez les
tuyaux à l’eau apprès l’essai d’étanchéité.
4B Special Precautions for LP Gas
LP Gas is heavier than air and can therefore more
readily collect or “pool” in enclosed areas if provision
for proper ventilation is not made. Be sure to pay
special attention to proper ventilation for LP gas.
Locate boilers a safe distance from LP gas cylinders
and filling equipment. In the United States, consult
the “National Fuel Gas Code” (NFPA 54 / ANSI
Z223.1, latest edition) or in Canada, the Propane
Installation Code (CSA-B149.1), any local codes and
fire protection authorities about specific installation
restrictions in your area.