Sterling Plumbing SDRIOM-2 User Manual

Page 11

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1. Modulating valve

improperly installed (or
see Symptom “L”).

1. Short circuit or no

voltage to the amplifier.

2. Open circuit in TD114

Remote Temperature
Selector circuit or wiring.

3. Short circuit in TS114

Discharge Air Sensor
circuit of wiring.

4. Faulty amplifier.

1. Short circuit or open

circuit in Modulator
Coil.

2. Plunger missing, jammed,

or improperly installed.

1. Incorrect by-pass

metering valve
adjustment.

2. Excessive negative

burner pressure.

11

Symptom

Possible Cause

Field Test

Remedy

A. No Gas Flow

B. Continuous Low

Fire (Electronics
Problem)

C. Continuous Low

Fire (Electronics
OK).

D. Incorrect Minimum

Fire Erratic or
Pulsating Flame

1. Arrow on side of valve

should point in direction
of gas flow.

1. Check for 24V AC at

amplifier terminals 7 & 8.

2. Inspect for loose or

broken wires between
amplifier terminals 1 & 2
and TD114 terminals 1 & 3.

3. Connect test resistor as

described in Preliminary
Circuit Analysis in Section
IX. Follow procedures
outlined.

4. Check items B1-3.

1. Measure resistance across

modulator terminals with
connecting wires detached.

2. Inspect. Plunger should be

installed to operate freely in
solenoid sleeve.

1. See valve adjustments in

Section IX.

2. Close main gas supply and

measure manifold pressure
with blower operating.
Reading should be less than
1.5” W.C. negative pressure.

1. Install properly.

1. Prove the power source.

2. Tighten connections or

replace wiring.

3. If modulating voltages are

obtained, check TS114
circuit for shorts. Replace
TS114 if necessary.

4. If items B1-3 check out, and

modulating voltages are still
not obtained, amplifier may
be assumed faulty. Replace.

1. Replace modulator head if

not approximately 45-55
ohms for M611 Valve and
60-80 ohms for MR212 Valve.

2. Clean or replace plunger if

necessary.

1. Adjust to proper minimum

fire.

2. If reading is greater than 1.5”

negative pressure, check for
clogged filters or other inlet
air restrictions. Consult
factory for other solutions.

United Technologies Electronics Controls
Operation of the Series 1016-400 Direct Spark
Ignition Control
On a call for heat a five second pre-purge is initiated.
Upon completion of the pre-purge, the gas valve and 60
Hz spark are energized. When flame is detected, the con-
trol enters the steady state heating condition. Steady state
heating will continue until the call for heat is satisfied.

If ignition is not achieved within 15 seconds, the control
shuts off the gas and locks out

.

If the trial for ignition has

been accomplished without ignition, the control shuts off

all outputs and enters lockout. Reset is accomplished by
cycling the power off for a minimum of 5 seconds.
If flame is lost once it has been established, the control will
shut off the gas valve within 0.8 seconds and locks out.

If flame is sensed during a purge period when no flame
should be present, the control will remain in purge with
the gas valve off until the false flame disappears.
If the gas valve is found to be powered when it should be
off, or not powered when it should be on, the control will
enter lockout with all outputs off. Reset is accomplished
by cycling the power off for a minimum of 5 seconds.

TROUBLESHOOTING GUIDE

Series 14 Discharge Temperature Control

Reproduced with permission from Maxitrol® Company

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