Midco RS40 - Manual (Page 5)

?? Set the thermostat heat anticipator for the total current draw handled by the
thermostat. The current draw of the ECONOMITE 24V operating circuit is 0.9 amps.
CAUTION: Label all wires prior to disconnection when servicing controls. Wiring
errors can cause improper and dangerous operation. Verify proper operation after
servicing.
_____________________________________
CAUTION: The available gas
pressure should be within the
limits shown in the SPECIFICA-
TIONS section. Excessive pres-
sure will damage Combination
Valve and Regulator. If the supply
pressure exceeds the 14.0" W.C.
maximum, a suitable intermediate
main regulator must be installed
ahead of the Main Manual
Shut-Off Valve shown in Figure 6.
?? The burner gas supply piping
should branch off from the main line
as close to the gas meter as possible.
Do not connect to the bottom of a
horizontal section. Use new black pipe
and malleable fittings free of cutting
and threading burrs or defects.
?? Provide a sediment trap, union
and 1/8" pressure tap in piping close
to burner as shown in Figure 6.
?? Use pipe joint compound
approved for use with Liquid
Petroleum Gases.
?? Piping must comply with local
codes.
?? To obtain the maximum firing
rate of 200 MBH, the NATURAL and
PROPANE gas supply piping must
be sized to provide minimum of
5.0" W.C. pressure to the inlet of
the Combination Valve when the
burner and all other gas utilization
equipment are on.
?? When pressure testing the
supply piping, the burner valve train must be protected. If the test pressure is 0.5 PSIG or less,
closing the Main Manual Shut-Off Valve will suffice.
CAUTION: If the test pressure is 0.5 PSIG or less, closing the Main Manual Shut-Off
Valve will suffice.
DANGER: Explosion hazard.
Do not use oxygen for pressure testing.
An explosion could occur during initial start-up.
?? If the burner piping must be rearranged because of space limitations, be sure to carry
out the general arrangement shown in Figure 6. Install the Combination Valve in any
position except up-side down.
?? When the burner is installed in jacketed equipment, it is recommended that the
Combination Valve be left adjacent to the burner within the vestibule and the Main Manual
Shut-Off Valve be installed outside.
_____________________________________
Standard burners are approved for use with NATURAL or PROPANE gas only, and should
be used only with the gas specified on rating plate.
?? A Standard Model RS40 Economite is shipped ready for NATURAL gas. It is field
convertible to PROPANE gas, see Table 3.
VI Piping
Pipe
Size
1 /
2
3 /
4
1
1 1 /
4
130
200
200
90
145
190
200
200 100
130
200
200 80
105
165
195
200
80
125
150
200
200
Type
of Gas
NATURAL
PROPANE
NATURAL
PROPANE
NATURAL
PROPANE
NATURAL
Approx. Capacity-MBH
Length of Pipe (ft.)
Table 2: Supply Pipe Capacities in MBH
Capacities shown are for a total pressure drop of
0.3" W.C. For higher permissible pressure drops,
consult your fuel supplier.
Source: Gas Engineering Handbook 1974
5
10 20 40 60 100
Figure 6: Piping Connections
VII Main Gas Spud
V Electrical Continued
Part 1 Installation
Part 1
Installation Continued