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Condenser Coil Repair - A crane is used here to lift a new condenser coil to a rooftop. The old condenser coil was leaking and could no longer be repaired. The process involved recovering all the refrigerant from the Trane rooftop unit.
The rooftop unit was then partially disassembled and the old coil cut out from the system taking great care and planning to ensure the new coil could be retrofitted to the old refrigeration piping system.
Good planning and skilled HVAC techs make the jobs go smoothly and make the replacement seem easy especially to the customer.
Condenser Coil Repair | Regulations for Refrigerant Leaks
The system holds approximately sixty-five pounds of R-22 refrigerant. The E.P.A. in accordance with the Montreal Protocol requires the system be repaired if it leaks more than fifty pounds of refrigerant a year. The solution here was to replace the coil rather than try to repair the old coil. After brazing in a new coil and filter driers, the system is leak tested with nitrogen to make sure all solder joints have integrity and will not leak when the refrigerant is charged to the system.
After all the checks have been made the unit is reassembled and a vacuum pump is hooked up to the refrigeration system. A vacuum is pulled and then nitrogen is reintroduced to the system. The nitrogen is released and another vacuum is pulled on the system. The is repeated one more time. This is called a triple evacuation and ensures that all moisture is removed from the system before the unit is charged with refrigerant.
An RTU Air Conditioner Unit is getting new air conditioner condenser coils because the old condenser coils were leaking. The old rooftop air conditioner condenser coils were losing more the 50 lbs. of r-22 refrigerant per year. By law and the E.P.A.section 608, the unit had to be condemned or the leaking rooftop condenser coils needed to be replaced.
The job required two technicians working a full day and then one had to return the next day to finish the job. Because the rooftop air conditioning unit served offices and those offices were served by the rooftop air conditioning unit during the week, the job was done on the weekend so the customer wouldn’t be uncomfortable.
The rooftop air conditioning unit worked well as new after the air conditioner condenser coils were replaced.
Condenser Coil Repair | Factors for Repair Vs. Replacing
It is recommended that an evaluation is done for the RTU air conditioner unit condensing coils and the unit as a whole. Sometimes, if you factor in the age of the unit, the cost of repairing the RTU air conditioner condenser coils, and the possibility that another major component could fail, it makes more sense to replace the whole unit rather than replacing a major component especially an air conditioner compressor or an RTU air conditioner unit condenser coil.
Always consult a professional when doing an analysis like this on an RTU air conditioner unit. Repairing the refrigerant leak is always the first choice in the factors and considerations however other things need to be considered also.
An old HVAC condenser coil needing repair. Refrigerant leaking condenser coils like these are common in condensing units over 15 years old. A sure sign of a leaking condenser coil or even an evaporator coil is the presence of oil between the tube sheets. Over the years the vibrations from the unit transmit to the tube sheet. Passing through the tube sheets are the copper u-bends.
The tube sheet eventually vibrates enough to rub a hole in the copper that makes contact with the tube sheet. The hole in the leaking condenser coil can be a tiny hole causing the refrigerant and oil to leak out slowly. The hole also caused a sudden catastrophic loss of refrigerant. Most commercial units are equipped with high and low-pressure switches which will lock out the compressor controls if the refrigeration circuit has too much pressure or if there is a sudden loss of refrigeration charge.
Condenser Coil Repair | Protecting the Equipment from Further Damage
This protects the compressor. Too much pressure can damage the mechanical components inside the compressor if the compressor were to continue running under a high-pressure situation. If a sudden loss of pressure was experienced by the equipment the refrigeration circuit would lose some oil and also deny the compressor of its designed coolant, the refrigerant.
Other problematic situations can occur by low pressure in the system. The low-pressure switch will prevent these problems when the unit experiences a low-pressure situation including a slow or catastrophic loss of refrigerant charge from a leaking condenser coil. Some units do not have low-pressure refrigeration switches so severe damage to the system could occur.
Condenser Coil Repair - HVAC Crane Lift
Technical Resource: Refrigeration and Air Conditioning Technology