R98V

Stat, indoor, or data pair dropped. The communicating thermostat is the system.

1. 1 Data pair, not 24 V

   On Rheem R98V indoor/outdoor comm is a data pair (AB, S1/S2, U, ComfortBridge, ComfortLink — whatever THIS plate uses). It is not a 24 V Y. Check polarity, continuity, and that nobody landed it on R/C. Data-pair landing and polarity. EcoNet is not R/W.

   Expect: Pair continuous, not shorted to chassis, polarity per the diagram.

2. 2 Power both ends, then the outdoor status

   Indoor transformer and outdoor control both alive. Read the outdoor LED / 7-seg. Water in the outdoor control is the usual dead-end after a storm. 24 VAC still required at the control — comm dead is not ‘no transformer’ until you measure.

   Expect: Both controls powered. Outdoor showing a comm or address state, not a blank board.

3. 3 Address / bias, then the control

   Communicating plates need a matching indoor address and sometimes a terminating bias. Swap is last: known-good pair + power both ends + correct address. One EcoNet control. Do not stack a 24V stat on the data pins.

   Expect: Indoor sees the outdoor. No comm code after a power cycle.

11 failed ignition, 12 low flame sense, 13 flame lost. Same meanings as the two-stage Rheem IFCs.

1. 1 Measure µA while it is running

   Do not clean first and guess. Series-µA the rod on Rheem R98V during a call. Falling µA is oxide, ground, or a dying flame. A hard drop is often the pressure switch or limit opening, not the rod. HSI, gas, rod, ground, manifold at the commanded rate — a valve that will not come off minimum looks like 11/13.

   Expect: Typically ≥ 1.0 µA DC on this family — confirm the door card. Rising while running.

2. 2 Rod, ground, then gas

   Clean the rod with a non-scratch pad — not sandpaper. Chassis ground to burner box and IFC (painted screw and missing star washer are classic). Then manifold on the stage that is dropping and confirm LP conversion leftovers. Do not treat these as EcoNet comm codes.

   Expect: Manifold on the rating plate. Solid burner-box ground.

3. 3 Prove it is not a switch opening

   Watch the live Rheem R98V display when flame drops. A PS or limit code that appears at the drop means the rod was a victim. Inducer, hose, vent wind, or a limit on a wrong heat tap.

   Expect: µA stable and the live code stays a flame code — then rod/valve/IFC. Otherwise chase the new code.

Overtemp / airflow.

1. 1 Airflow before you touch the limit

   On Rheem R98V a limit is airflow or overfire until proven otherwise. Do not replace the limit first. Filter, blower wheel, A-coil, and the heat-speed setting for THIS motor (tap, model plug, or communicating CFM — not a sister SKU chart). EcoNet heat CFM, filter, coil, rise.

   Expect: Rise in the rating-plate window. Static vs this cabinet’s blower chart.

2. 2 Measure static and temperature rise

   Total external static vs the Rheem R98V blower chart for this cabinet size. Supply minus return rise after 8–10 minutes. A new 5" media cabinet or closed supplies will trip this all winter. A 24V fallback (if someone forced one) will not modulate airflow correctly and will trip 22.

   Expect: Rise typically 35–65 °F — rating plate wins.

   If fail: Fix the restriction or the heat-speed setting. The limit is doing its job.

   If pass: Airflow in range → step 3 (overfire / limit itself).

3. 3 Overfire, then the limit circuit

   Clock the meter / manifold on the stage that is tripping vs the rating plate. Then ohm the limit after it cools — a limit that never recloses is failed. Rollout in the same circuit is a different call (see rollout on this door card).

   Expect: Manifold on plate. Limit closed when cool.

Modulating inducer / pressure did not prove at the commanded %. Not a simple two-switch tee like R96TA or the VA 45/46 split.

1. 1 Prove inducer and the live code

   Do not pull power — that clears the Rheem R98V active code. Write 45 / 57. Is the inducer spinning on this call? Silent inducer is not a pressure switch. Vent, trap, collector, inducer throughout the rate, pressure hose / transducer path.

   Expect: 120 VAC at the inducer on a heat call. Wheel turning.

   If fail: 120 VAC missing → IFC / door switch / incoming power. Voltage + dead motor → inducer.

   If pass: Inducer running + this code → trap, hose, switch, vent (step 2).

2. 2 Trap, collector, and the hose

   A drowned 96% trap will not make collector pressure. Pull the trap, flush it, confirm the collector box and inducer outlet are not full. Hose cracked, off the port, or full of water fakes an open switch. Do not replace ‘the low PS’ off an R96TA card.

   Expect: Trap flowing, hose dry and downhill, ports not swapped on a two-switch board.

3. 3 Switch ohms, then vent load

   Ohm the pressure switch: NO, must close when that inducer speed is making the collector setpoint. If the switch is good, walk the PVC — bird screen, ice, long 2" run, wind, shared chase. Watch whether the fault appears only at higher % — that is vent capacity, not a dead switch.

   Expect: Switch closes on known draft. Vent unrestricted.

   If fail: Replace the open switch only after the vent and trap are proven.

   If pass: Switch closes on draft and the code stays → IFC input.

IFC self-fault.

1. 1 Write the live code and watch one cycle

   On Rheem R98V read EcoNet IFC + communicating stat (Prestige / Endeavor) before you pull power. Write 93 exactly. Watch one full sequence and note which step dies. Stat log + board digits. Persistent 93 after a clean power-up is the control.

   Expect: Call: EcoNet stat requests a % capacity. Valve and inducer modulate; blower CFM follows. This is not W1 then W2.

2. 2 Prove the circuit this code names

   Wet board from a 98% leak, polarity, leftover 24V landing on the data pair.

   Expect: A measured open, short, or out-of-range reading — not a guess.

3. 3 Confirm with a number, then the next part

   If the named part measures good, the IFC input/output or a related code on this same plate is next. Do not apply a sister-SKU chart.

   Expect: EcoNet pair: Communicating data. Not 24 VAC. Polarity. One master control.