Hastings DIRECT GAS FIRED ELECTRIC STEAM, Инструкция по установке и обслуживанию

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5. If unit does not heat air, check to see if:
a. Modulating step controller is operating through all heating steps.
b. Sub-circuit heating element fuses in circuit.
c. All magnetic heating element contactors are operational
d. Heat limiters are n.c. and in the electrical circuit.
NOTE: Electric heating SBE units may not be furnished with a disconnect switch or circuit breaker. If any
service work is to be required, opening more than one disconnect switch may be required to com-
pletely de-energize system. Make no attempt to re-wire any heating element circuits if a failure occurs.
Con-
tact home office.
N. TROUBLE SHOOTING THE STEAM OR HOT WATER SB UNIT
1. If blower fails to operate, check to see if:
a. Main disconnect switch or circuit breaker closed.
b. All main fuses (if disconnect switch used) are in line.
c. Control transformer is supplying 115 volts to control circuits.
d. Season switch in remote control panel in “summer” position, or if in “winter” position that heating control relay
coil is energized and contacts are closed.
e. Freezestat(s) are n.c. and in the electrical circuit.
f. Freezestat control relay coil energized and contacts are closed.
Also check the following optional controls, if used, to see if:
a. Damper motor end switch is closed (damper motor must be full open).
2. If blower runs, but remote control panel blower light doesn’t come on, air proving switch is faulty, discharge is
blocked, belt(s) are loose and slipping, or blower is running backwards. Also check to see if air proving sensing
tube is plugged or has been crimped.
3. If blower operates and blower signal light is on, but system fails to heat air to desired temperature, check to see if:
a. Season switch in remote control panel is in ”winter” position.
b. Heating relay contacts are closed.
c. Two position or modulating valve (and controller if modulating system) is functioning properly.
d. All steam and hot water lines are open and free flowing.
e. Steam pressure, water temperature and flow rates are per specifications.
f. On two coil systems that outside air temperature controller is functioning properly.
NOTE: We cannot guarantee coils against freezing, but the likelihood of freezing can be minimized if the installer
takes the following precautions:
1. Provide adequate sizing of condensate return lines, traps, and vents to provide for a speedy flow of condensate
from the coil
2. Do not bush or reduce return trapping size.
3. Do not drain steam mains or branch lines through coils. Steam lines should always be drained ahead of control
valves.
4. When more than one coil section is installed, a separate steam trap must be provided for each.
5. Use only bucket or float and thermostatic traps for condensate removal. Use thermostatic traps for venting only.
6. Steam traps should be sized for three (3) times the calculated condensate load at coil design conditions.
7. Traps should be selected for the pressure differential across the trap – not boiler pressure.
8. Strainers should be installed ahead of traps to prevent dirt and sludge from affecting operation.
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