Loose insulation can be pulled into or against the blower assembly and block airflow. The switch shuts off the compressor if the discharge pressure rises above the factory setting. If you see a high-pressure switch tripped in the winter, the issue is most likely at the indoor portion of the heat pump system. Most will also have an amber (green) light that indicates when the heat pump is operating in the emergency mode. To clear the condition, cycle the heat pump, on and off, up to 3 times. Some HVAC systems (air conditioners, heat pumps, refrigeration equipment) include other sensor switches that may include an electrical pressure or temperature transducer/sensor (photo at left) or an air conditioning or heat pump pressure sensing switch that detects improper (too high) or [in some systems including automotive air conditioning] too-low refrigerant pressures in the system. I would suggest that you try to reset the tripped switch, usually by pushing it in with your finger. Now the Heat pump worked without a hitch all night. Our default site experience provides general information and content for every region served. The switch is an pressure switch located on the discharge line of the compressor. Heat Pump Troubleshooting | No Heat or Cool Checklist. This pressure switch (see photo of switch) is rated to open at 630psi and reset at 480psi with a +/- range of 25psi. 4 - Wait a few minutes (3 to minutes should be long enough)5 . Insure all the registers are open. Sign up and receive helpful updates from Ferguson HVAC. Heat Siphons are a common Heat Pump used for heating water in pool and spa applications. The switch shuts off the compressor if the discharge pressure rises above the factory setting. Below, we’re taking a look at how a pressure switch functions, simple troubleshooting tips, and nine common well pump pressure switch problems. Heat pump does not run or short cycles and control board display shows FAULTHIGH REF PRESSURE When the head pressure builds too high, the high pressure switch will open causing the heat pump to shut off immediately. An accumulator is installed in the return line to trap and store the refrigerant liquid before it can enter the compressor. The heat pump operation is controlled by a room thermostat. However, they are commonly found on heat pumps. Make sure your thermostat is set to “cool” before you switch the power on completely. Troubleshooting Guide Alarm high pressure The operating pressure switch does not open but the heat pump opens at high pressure Action: Check that the operating pressure switch opens at the correct pressure, using manometer apparatus. This high-pressure switch has the opening range of 605psi to 655psi and reset when the pressure drops in the range of 505psi to 455psi. Go figure. Many systems are set to a lower speed at the factory to achieve a better SEER rating. 5. Check that both the cables for the operating pressure switch are in position If the pressure switch is closed, bridge the operating pressure switch cables temporarily and switch on the voltage to the heat pump again. Do not assume the motor is on high speed. Many pressure switches have an opening pressure tolerance of +/- 10%. This is sometimes hard to find because the insulation will go back in place when the blower shuts off or the panel is removed. Check to see what speed the indoor blower motor is running at. Then switch the breaker back on. This shows how to reset a low pressure cut of switch. The switch opens on low-pressure drop in the discharge line to shut off the compressor. 400 CFM per ton is recommended for heat pump systems. In the case of a heat pump in cooling mode, the high pressure switch is used to make sure that outdoor unit can reject heat with the … Within 4 seconds the gas Burner fires-up BUT safety shutdown from the Ignition Control Block. This should restore proper operation of the Heat Pump In an effort to better serve our customers, this content is designed to be tailored to our individual service regions. Outside it is at the freezing mark. Sorry, there are no results found near this location. This seems to happen overnight. Please try again. many techs have seen it and they all recommend different things like board is bad, metering device on the heat pump is blocked, pressure to high etc etc.. Pressure too high has … + Change the Control Box if the Gas valve is OK. b. 5 - hen turn T everythingback ON in the reverse order. Note: do not allow pressure to go above the rated trip value of the high-pressure switch. In heating, the indoor coil is seeing high pressure. The AUTO mode provides the heat pump with the ability to automatically switch back and forth between the heating and cooling modes in order to maintain a predetermined comfort setting. So if you switch to a backup electric heat source, you’re also switching to paying two to four times as much for the same amount of heat. An auto-reset high-pressure switch (single pole, single throw) is located on the liquid line. Ensure that the setpoint setting is at the desired settings. If the pressure switch does not trip until it is within rated range, you will need to diagnose further. II. Ice or Freezing | Hate Pump Troubleshooting No Heat. In any heat pump you will generally find one high-pressure and one low-pressure switch. The system switch is used to set the heat pump for heating, cool- ing, or auto operation. If the switch trips before the rated pressure range, replace the switch. The switch resets (closes) when the pressure drops below a factory-preset minimum low-pressure point. Well this morning it was a little chilly in the house so I reset the low pressure lock out condition by cycling the air handlers circuit breaker. Remove the cover cap from the cut-off switch by loosening the cap nut over the plastic box by hand … If the high pressure switch opens at a lower pressure than indicated there is a fault in the high pressure switch Taking into account the maximum working pressure, the type of reset on the high-pressure side and the required switch points you are already half way there. Condenser fan runs, compressor doesn’t. This will cause the discharge pressure to rise. 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One of the first things to check is the pressure switch itself. Check selections on the thermostat. If the heat pump system is designed to provide supplementary heat when there are excessively cold temperatures, the auxiliary heater is controlled by the thermostat through an emergency heat mode. They have a problem compressing the refrigerant liquid. If it does may it be full of gookus that I could clean out? Airflow setting can be found in the installers guide that is supplied with every unit (Blower Chart). The emergency heat mode locks out heat pump operation while the auxiliary heater is operating. Rheem Air Conditioner or Heat Pump Reset Button Location The Rheem outdoor ac unit reset button is a high pressure reset that is meant to protect your system from further damage.