Heating, Air Conditioning, Fridge, HVAC/hi pressure switch


I have a rheem heat pump,RPGB-025JAZ, 1996 MODEL, it works fine in a/c mode but when I switch to heat mode it runs 10 minutes and the hi pressure jumps up and the Hi- pressure switch trips, I can wait 5 minutes , push the reset and it will start and it does the same thing, I think the reverse valve may not be fully engaging causing a bleed by making the hi pressure increase


You may have to check your indoor coil inlet side ,it could be quite dirty raising your head pressure, Yours being a 1996 Model year, and tripping the HPC also a plugged air filter  , many registers closed off.Return air register is partially blocked. Anything that restricts air flow across the indoor coil ,while in heat mode.Chances are if the RV switches in A/C mode and cools fine your RV is OK. There are guidelines how to check a RV , you would need a multi probe thermometer to clamp on the RV and take temp. ,if the temp. exceeds around 10 degree it's not shifting completely. Your HPC could also be out of calibration, and trip at a lower setting than what it's rated for.Usually they trip at 385 PSI plus or minus.  You may be running a lower  head pressures in Cool mode than in heat mode.Also double check the indoor blower wheel lobes to make sure they are clean and is scooping up the correct amount of air to send across the indoor coil.You may have a kinked vapor line ( known as a suction line in A/C mode ) that's restricting the correct amount of refrigerant reaching the outdoor coil ,while in heat mode.Typically if the RV does not switch 100% your high side pressure dumps into your low side , and your pressures are lower than normal, not higher.

Heating, Air Conditioning, Fridge, HVAC

All Answers

Answers by Expert:

Ask Experts




40+ years diversified experience.An HVAC/Refrigeration Self Employed Contractor since 1986. NATE Certifield. Answer questions pertaining to Residential and Commercial Air Conditioning , Warm Air Heating, Heat Pump systems.Mechanical and Electrical troubleshooting of these systems.Be as detailed as possible when describing problem.Packaged unit or split systems.No appliance questions.


Installation and Troubleshooting, Mechanical and Electrical, in following areas, Refrigeration ( Walk In and Reach In Coolers and Freezers ) Commercial Roof Top and Packaged Heating/Cooling ( Natural Gas,Propane, Electric, and Heat Pumps ) Computer Room Air Conditoning Systems,Commercial Residential Packaged and Split Systems Air Conditoning and Heat Pumps.Warm Air Oil , Natural and Propane Gas Heating systems.

Graduated from Private Technical School in 1975. An HVAC/Refrigeration Contractor . Have Unlimited Heating/Piping and Cooling Contractor License.Limited Sheetmetal Contractors License.NATE Certifield. York Certifield Master Heat Pump Technician 1986. Served 33 years combination Active Duty Air Force , Air Force Reserves and Air National Guard in the HVAC/Refrigeration Shop/Mechanical Shop. Troubleshooting/Installing HVAC/Refrigeration Equiptment Worldwide. Retiring in 2003 as a Senior NCO ,and a Mechanical Superintendent.

©2016 About.com. All rights reserved.