Slant/Fin EH-M2 - Manual (Page 4)

4 EH-M2-40 Boiler Operation and Installation Instructions
Table 1. Lug Sizes
Table 3. Current Ratings
Table 2. Flow Switch Size Selection
† Leg with the highest value of line current of an unbalanced 3-phase load.
‡ 125 VAC maximum rating of all hot conductors.
PIPING
Air Separator and Expansion Tanks
The recommended piping arrangement is shown in figures 2
through 4. Note that there is a built-in air eliminator in the heat
exchanger (air vent, however, is by others). The air vent tapping
is 13mm (1/2”). A bushing (by others) to suit the size of the air
vent thread is required. Additional air vents should be installed at
points just upstream from all drops in elevation of the piping
system (high points).
Relief Valve Discharge Piping
Use same size or larger piping than valve outlet piping. Must terminate
152mm ( 6”) minimum from floor with a plain ( no threads) end.
Place a bucket under pressure relief valve discharge piping. Make
sure discharge is always visible. DO NOT hard-pipe to drain piping.
Flow Switch
THE INSTALLATION OF A FLOW SWITCH IS STRONGLY
RECOM MENDED. It is intended to prevent the burnout of heat -
er elements should the circulator fail, or should air accumulate
in the boiler due to faulty air elimination (see Table 2 for flow
switch size required). FLOW SWITCH MUST BE IN STALLED IN
HORIZONTAL POSITION. IF A FLOW SWITCH IS NOT USED
JUMPER THE “FF” TERMINALS (JUMPER NOT SUPPLIED.)
Bypass
The bypass shown must be set so that a sufficient amount of
water can circulate through the boiler when all zone valves are
closed. (See Figure 3.)
Multi-zone Balancing
Raise all zone thermostat settings and verify that all zone valves are
open (not bypassed). Close all electrical panels. Turn on 10 amp
control circuit breaker ONLY. Pump should operate. Note the pressure
reading on the pump discharge. Lower each zone thermostat setting
to close corresponding zone valve. Adjust the, corresponding balanc-
ing valve to maintain pump discharge pressure. The pump discharge
pressure should remain the same when all zones are in bypass or
when all zones are open or any combination of opened and closed.
See Figure 3 & 4.
WIRING
To wire the electric boiler, perform the following procedures:
1. Wall Thermostat Flow Switch and Circulator
• All circuit breakers ahead of and at boiler must be OFF. Remove the
Control Panel (left-hand front) Cover by removing 5 screws from top,
bottom and side flanges.
• The right-hand compartment under the Control Panel Cover contains
a terminal board marked, (SLANT/FIN "INTERFACE BOARD"). Wire a
2-wire 24V room heating thermostat or the auxiliary end switch termi-
nals of zone valves (see Figure 5) to terminals 3 and 4 at this time.
The 1 and 2 terminals are for the flow switch. The flow switch circuit is
a low voltage circuit.
• Wire the circulator and connect 115V wires and conduit through 13
mm (1/2") K.O. provided on bottom left hand corner, to the "INTER-
FACE BOARD" at terminals "L" and "N", where it is marked "CIRC.
PUMP".
2. Service Connections and Electrical Ratings
A. All circuit breakers ahead of and at boiler must be OFF. Remove
the Service Connection Panel (right hand front) Cover by removing 5
screws from the top, bottom and side flanges (see wiring diagram on
back of the Service Connection Panel and Figure 5).
Model Phase
Distribution
Block Wire Size
CU
Ground Lug
Wire Size
CU
Neutral Din
Rail Mount
CU
EH-40-M2
EH-8-M2 thru 32-M2
EH-12-M2 thru 40-M2 1
1
3 2-3/0 MCM CU
6-2/0
6-2/0
6-2/0
6-2/0
6-2/0 14 Min.
14 Min.
14 Min.
The neutral tap is for the circulator and control transformer.
† Aluminum conductors may be used, lug size, conduit size, ampacity and all applicable codes permit-
ting. However, aluminum conductors may not be used for models over 32kw.
Model
Flow Switch
McDonnell
& Miller No.
Pipe
Size
Pipe Length
of Flow
Switch**
EH-40-M2
EH-8-M2 thru 32-M2 FS8W
FS4-3T3-1
1-1/4"
1"
8-1/2"
6-1/2"
SINGLE PHASE 3 WIRE, 120/208V‡
Basic Model
No.
Heater Amperes
@ 208V
EH8-13-8-M2
EH10-13-8-M2
EH12-13-8-M2
EH16-13-8-M2
EH20-13-8-M2
EH24-13-8-M2
EH28-13-8-M2
EH32-13-8-M2*
EH40-13-8-M2
29
36
43.4
58
72
87
101
116
145
SINGLE PHASE 3 WIRE, 120/240V‡
Basic Model
No.
Heater Amperes
@ 240V
EH8-13-4-M2
EH10-13-4-M2
EH12-13-4-M2
EH16-13-4-M2
EH20-13-4-M2
EH24-13-4-M2
EH28-13-4-M2*
EH32-13-4-M2*
EH40-13-4-M2
33
42
50
67
83
100
117
133
167
THREE PHASE 4 WIRE, 120/208V
WYE CIRCUIT ONLY‡
Basic Model
No.
Heater Amperes †
@ 208V
–
–
EH12-34-8-M2
EH16-34-8-M2
EH20-34-8-M2
EH24-34-8-M2
EH28-34-8-M2
EH32-34-8-M2
EH40-34-8-M2
–
–
43
58 †
72 †
69 †
69 †
83 †
108 †
THREE PHASE 4 WIRE, 120/240V
DELTA CIRCUIT ONLY‡
Basic Model
No.
Heater Amperes †
@ 240V
–
–
EH12-34-4-M2
EH16-34-4-M2
EH20-34-4-M2
EH24-34-4-M2
EH28-34-4-M2
EH32-34-4-M2
EH40-34-4-M2*
–
–
50
67 †
83 †
79 †
79 †
96 †
125 †
** Straight pipe upstream and downstream.