Heating, Air Conditioning, Fridge, HVAC/heat pump running

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Question
Our home has 2 heat pumps but no back-up furnace so we have a new experience. The heat pumps seem to run virtually all of the time--even though one is only a year old. It has been very cold. Is this normal? I have been told that the "emergency heat" cycle on the thermostat provides direct electric heat from the air handler. If it is very cold should I set thermostat to "emergency heat"?

Answer
Paul,

Typically you have an emergency heat position on your stat , and is used when the outdoor unit fails or if it's extremely cold outside.  Typically you should have a two stage heat one stage cool stat . In heat mode the first stage operates the Heat Pump only , as the Heat Pump can not keep the residence warm ,after aprox. 2 degree lower indoor temperature the 2nd stage makes bringing on the backup heat . Depending on your electric heater size when in 2nd stage heat you could bring on 100% of your heat , 50% or 75% percent. If you put to emergency heat you should be bringing on 100% of your electric.

To give you an idea how much electricity a heating element uses based on aprox. 220volts

A 5 KW Heater uses 18-20 Amperage
A 7.5 KW Heater uses 28-30 Amperage
A10 KW Heater uses 38-40  Amperage

A typical outdoor heat pump section uses aprox 9 Amprege

Setting it to all electric is your choose , expect a large electric bill thou.

Have both system checked in the fall occasionally as there are more things happening during heat mode than cooling. Checking Proper defrost operation , making sure 2nd stage heat works , if your heaters are wired to come on during defrost ( to help temper the cold air coming out of your vents ) they can check that also.

Depending on blower fan speed and outdoor temperature and even indoor return temperature your looking for aprox. 20 degree temperature rise at the fan section from the return to the supply .  

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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.

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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.

Education/Credentials
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.

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