93 Internal control fault

What the control is telling you

Internal furnace control fault. 802P/R95P: hard lockout - internal fault, or voltage on the gas valve contacts (welded relay) that does not clear when the inducer cycles; cycling the heat call will not reset it. RGPE/RGLE: CONTROL FLT, Call For Service. 802P manual lists 93 in the flowchart but not the main fault table.

Applies to: 802P/80MDP (802PA050-150); R95P (R95PA040-115); RGPE/RGLE 2-stage 80+

Likely causes

• IFC internal failure
• Gas valve relay welded
• Miswiring feeding voltage to the gas valve circuit

Test and repair steps

1. Warning: If flame is present or gas will not shut off with no call, close the manual gas valve first.
2. Cycle power and see if the fault returns.
3. Check wiring, ground and connections before condemning the IFC - most failures are not the IFC.
4. RGPE/RGLE when replacing the IFC, move the original memory card to J15 of the new control.
5. Replace the IFC if the fault persists.

Settings for these units

• Clearance to combustibles (all models) · R95P
• Filter sizes as shipped, upflow (Table 19) · RGPE/RGLE
• Reduced clearance to combustibles, upflow/horizontal (Fig. 4) · Rheem/Ruud 802P / 80MDP 80% two-stage furnace (UT 1028-928 IFC)
• Reduced clearance to combustibles (Fig. 3 and 4) · RGPE/RGLE