Bosch EP036 - User Manual

Questions and Answers

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Edwin LewisAug 17, 2025
What to do if my Bosch EP036 Heat Pump is off on high pressure control?
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  Michael PerezAug 17, 2025
  If your Bosch Heat Pump shuts off due to high pressure, it could be due to several reasons. In cooling mode, check for inadequate water flow, excessively warm entering water temperature, or a scaled or plugged condenser. In heating mode, ensure adequate airflow by checking for an inoperative blower, clogged filter, or restrictions in the ductwork. Also, the unit might be overcharged with refrigerant, so reclaim the excess, evacuate, and recharge it with the factory-recommended amount. Finally, inspect the high-pressure switch for defects or improper calibration.
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Susan HoodAug 21, 2025
Why is the blower operating but the compressor not in my Bosch Heat Pump?
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  jameskristineAug 22, 2025
  If your Bosch Heat Pump's blower is running but the compressor isn't, check the thermostat settings, calibration, and wiring. Inspect for loose or broken wires at the compressor, capacitor, or contactor. Check the UPM board's red default LED for a Blink Code. If the compressor is cool and the overload won't reset, it may need replacement. A compressor motor grounded internally to the shell also necessitates replacement. After the compressor cools, check the continuity of its windings; open windings indicate the need for a replacement.
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Mark DavisAug 27, 2025
What causes a Bosch EP036 to turn off on low pressure control?
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  Michael LarsonAug 27, 2025
  If your Bosch Heat Pump is turning off due to low pressure, the suction pressure might be too low. In cooling mode, this could be due to inadequate airflow, excessively cold entering air temperature, an inoperative blower, a clogged filter, or ductwork restrictions. In heating mode, it could be due to inadequate water flow, excessively cold entering water temperature, or a scaled or plugged condenser. Also, the unit might be low on refrigerant, so check for leaks, repair them, evacuate the system, and recharge it with the factory-recommended amount. Finally, inspect the low-pressure switch for defects or improper calibration.
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Christina SotoAug 31, 2025
Why does my Bosch EP036 unit short cycle?
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  Kelly WolfAug 31, 2025
  If your Bosch Heat Pump is short cycling, it might be oversized for the space, so recalculate the heating and cooling loads. The thermostat could be installed near a supply air grill; if so, relocate it and readjust the heat anticipator. Also, check the wiring and controls for a defective or improperly calibrated low-pressure switch.
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devin11Nov 6, 2025
How to troubleshoot a Bosch EP036 Heat Pump that does not run?
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  Joanne RobertsNov 6, 2025
  If your entire Bosch Heat Pump unit isn't running, start by ensuring the power supply is on and the disconnect is closed. Check for blown fuses and replace them or reset the circuit breaker, making sure you're using the correct fuses. If the voltage supply is lower than the minimum specified on the unit's data plate, contact your local power company. Also, check the thermostat settings, calibration, and wiring. Set the fan to “ON”—it should run. Set the thermostat to “COOL” at the lowest temperature; the unit should cool. Set it to “HEAT” at the highest temperature; the unit should heat. If the blower or compressor doesn't run in any of these cases, the thermostat might be miswired or faulty. Verify 24 volts at the low voltage terminal strip between “R” and “C”, “Y” and “C”, and “O” and “C...
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Jessica DanielsNov 10, 2025
Why is my Bosch Heat Pump providing insufficient cooling or heating?
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  Bernard GillespieNov 10, 2025
  If your Bosch Heat Pump isn't providing enough cooling or heating, several factors could be at play. First, the unit might be undersized, so recalculate the heating or cooling loads. Adding insulation and shading might help. Check for air leaks in the ductwork or from outside through doors and windows. Ensure adequate airflow and proper air distribution, and replace any dirty filters. A low refrigerant charge can cause inefficient operation, so check the refrigerant levels. Inspect the compressor for defects; low discharge and high suction pressure indicate it's not pumping correctly, so replace it if needed. A defective reversing valve can also cause problems by bypassing refrigerant, so consider replacing it. Compare operating pressures to the unit's pressure/temperature chart. Check the...