Heat & Glo · Gas fireplace
2 Flash 5-minute lockout
What the control is telling you
The DSI module tried to light the burner and failed, so it locked out for 5 minutes. LED pattern on the DSI module: slow flash = normal, no call for heat; fast flash = normal, calling for heat; two flashes = 5-minute lockout; steady = hard lockout / control failure.
Applies to: Older Heat-N-Glo DSI gas fireplaces with RAM 1MC1-01/-05, RAM-1-RS, CFX-DA, Grand-50-C (120 VAC modules); LED applies to RAM 1MC1, CFX-DA and Grand-50-C
Likely causes
- Gas shut-off closed or air in the gas line
- Ignitor not over the burner ports, or sparking at the base instead of the tip
- Burner ports blocked by embers, or plugged burner orifice
- No 110/120 VAC reaching the gas valve (MV / MV RTN) or failed valve
- Poor ground or reversed polarity, so flame is not sensed
- Open high-temperature limit switch (units that have one)
Test and repair steps
- Reset turn the On/Off rocker (or wall switch on CFX-DA) off and on, or cycle the breaker.
- Watch a light-off. If the ignitor sparks but the burner does not light, go through: gas shut-off on, purge air from the line, nothing blocking the valve, embers not covering the ports, orifice clean, ignitor positioned over the port holes.
- Make sure the spark jumps at the electrode tip; a spark at the base or a cracked ceramic means a new ignitor.
- With the switch ON, measure MV to MV RTN on the module: 110/120 VAC expected. Voltage present but the valve does not open = replace the valve.
- On RAM 1MC1 valves check wiring valve terminal 1 (white) to 3, terminal 2 (blue) to 4.
- If the burner lights then drops out Check polarity: meter from 120 VAC HOT on the module to ground should read 110/120 VAC; from 120 VAC RTN to ground should read 0 V. If reversed, shut off power and swap hot and neutral at the junction box. Also confirm the junction box and burner are grounded and the ignitor probe sits in the flame.
- Warning: Disconnect 110/120 VAC before checking wire connections or changing parts.
Models that show this code
5 models in DSI
Other codes on the same units
- LED Off LED not flashing - no power to module
- Steady Flash Hard lockout - control failure
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Source: Heat-N-Glo DSI / HSI Troubleshooting Guide (Professional Development), LED codes and RAM 1MC1 / CFX-DA / Grand-50-C sections, p.6-11, 34-38, 42-45. Summarized in our own words; check the original manual for your model.
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For licensed technicians. Gas, electrical and refrigerant work must be done by a qualified, licensed person. Shut off power and gas before servicing, never bypass a safety control, and follow the manufacturer’s manual for the exact model; it and local codes always take priority. HVACopedia is not affiliated with any manufacturer; brand and model names only identify the equipment.