Proper and regular heat pump maintenance is crucial for a long-term and economical heating and cooling operation. If the unit is not cleaned and maintained per instructions and manual, it might deteriorate over time, losing the efficiency and performance, or simply malfunction. Note that the electric power must be turned off before performing any maintenance on the heat pumps. Below are the most common and basic steps (checklist) that should be taken to prevent future problems and unwanted costs. All the steps are grouped into two categories, maintenance of the outdoor and indoor units.
Check out the outdoor evaporator coil for dirt and any kind of debris that might be covering the coil, as it can reduce the heat transfer between the refrigerant flowing inside the coils and surrounding air that carries the “heat”. Don’t use the power washer as the water pressure might damage the coil fins – the garden hose or wet/dry vacuum should do the work.
Inspect the cabinet and cabinet fasteners - repair or replace insulation, replace lost fasteners, tighten loose fasteners to maintain the rigidity of the structure.
Ensure the proper clearance around the cabinet for an unrestricted airflow. Remove any weed, plants, shrubbery, debris, leaves, and branches from and around the outdoor cabinet to avoid unit overworking.
Clean debris and dirt from the blower’s fan blades.
The buildup of snow and ice restricts the airflow and should be cleaned around and from top of the unit.
Inspect the base pan for any obstructions in the drain openings and clean it. Proper drainage of the base pan eliminates water and build-up ice inside the outdoor component.
Inspect coil fins – clean and straighten it if bent.
While the compressor does not require any oiling, lubrication might be required for the fan motors whose bearings are not sealed. This is not needed for the sealed bearings.
Check out the electrical connections and wiring for any looseness or damages. Repair the connections if you see any burned elements and make sure the connections are tight.
Make sure all the refrigerant tubing, joints, components and coils, are not leaking.
Check the level position of the outdoor unit occasionally, because the support base can shift and when the unit is no longer leveled it causes water collection and improper drainage.
Heat pumps that are installed close to the seashore require additional maintenance due to the corrosive airborne ocean salt exposure. The recommendation is to wash all the exposed surfaced every 3 months at least.
It is recommended, at least once in 6 months, to clean or replace the filters. This task can be done even earlier if the surrounding air is making filters dirty, which might result in the air flow restrictions. According to Trane and other manufacturers, this should be done once a month, or as needed. This helps in improving the indoor air quality. Use the same size and type that was originally supplied.
Inspect the cabinet, cabinet fasteners and insulation – repair or replace as needed.
Ensure that there is a proper clearance around the cabinet – it should meet the requirements.
If possible, check out the ventilation ducts for any obstructions – at least once a year. For the proper work of heat pumps, the air flow must be coming in sufficient amount with no obstructions.
Also, see is there any air leakage in the ducts and seal it if possible.
Since the heat pump removes humidity from a home during the cooling season the water will be removed through the condensate drain. Make sure the drain system is not clogged.
Check the condition of the insulation (pipes for example). If it is ripped replace or repair it.
Inspect is there any refrigerant leakage, or if the refrigerant level is low - call the professional to recharge it.
Check out the electrical components: relays, circuit boards, capacitors, wiring… found in the control box, and tighten any loose connections, check if any is damaged. Measure the voltage and current, because the faulty connections/elements can lead to an unsafe operation and reduce the life of the parts.
Inspect fan belt for tightness and wear. Lubricate motor if needed (older models).
Check for the proper function of the thermostat. The programmable thermostat should be set once and left alone because the system will perform most efficiently when the thermostat is in control. Ensure that the system starts, operates and shuts off properly.
Set the indoor thermostat on “auto”.
Make sure that heating is locked out when the thermostat activates cooling process and cooling is locked out when the thermostat call for heating.
Test all joints, refrigerant lines and components for leaks - clean and repair if necessary.
Rattles can be fixed by tightening the loose parts.
Other recommendations; unless the heat pump uses the variable speed fan motor, continuous fan operation can degrade the performance – so avoid it.
While the heat pump is working check out the following and look for the abnormal noise or unusual smell.
If you plan to hire a technician, he can also check the heat pump characteristics, volts and amps, temperature rise, airflow rate, refrigerant and gas pressure, temperatures and make necessary adjustments.
Follow the manufacturer’s instructions and recommendations.
The above heat pump maintenance tips are used to prevent any major problems with the heat pumps. The noise coming from the unit is considered normal as long as it is within the specifications. Squealing or grinding noise is something that needs to be checked for element failure or looseness.
During the heating operation, when the heat pump is exposed to the freezing temperatures, and when the system uses the defrost cycle automatically to melt the ice or snow, the fog or steam rising and a higher sound level might occur.
As seen from above, there are many heat pump maintenance tasks that can be performed by the homeowner. But there is also more more which should be done by the professional:
If you are not handy with the electrical work, talk to the technician.
The above heat pump maintenance tips are the most common recommended by the manufacturers. The preventive maintenance is ensuring trouble-free heating/cooling operation and peak performance. In order to prevent the heat pump failure when you need it the most, pre-season maintenance (spring and fall) should be also considered – at least to have a piece of mind. If your heat pump is more than 10 years old, and it is under-performing, maybe it is time to start shopping for a new, more efficient one.
Word of caution: According to the manufacturer’s guideline, any attempts at “do-it-yourself” repairs might void the remainder of the warranty.