What causes evaporator coil icing&how to fix it?
This article series explains the causes & cures for evaporator coil icing: the problems of ice and frost formation in air conditioning system air handler units, blower units, or AHU's, duct work, or other air conditioning system components. A freezing or frosted A/C coil blocks air flow and leads to loss of cooling.
Why does my air conditioner keep icing up?
Another cause of icing is the control board not sending the signal to the compressor to shut down meanwhile the blower has soppped and the louvers has closed. Replace the control board or install a new seperate thermostat
Why is my evaporator freezing up and freezing up?
A completely iced evaporator is normally the result of a totally different system problem. Either there is a defrosting issue or little or no airflow across the coil. So, before deciding the cause of the icing too quickly, look closer at the coil, and see how the ice is developing.
How to diagnose an icing problem on a commercial cooling system?
If an icing problem is occurring on commercial cooling systems, in addition to checking the refrigerant charge and air flow, the service technician will also check out the defrost cycle timer. On 2020-11-15 by (mod) - how much refrigerant loss before we see a malfunction ?
But Ice on an Air Conditioner Is a Sign of a Problem!
The truth is that the appearance of ice—usually along the indoor evaporator coil—indicates something is wrong with the air conditioner. For reasons we’ll look at in the next section, the evaporator coil is staying colder than it should, which causes the moisture that condenses along it to freeze.
Reasons This May Happen
The air conditioner is losing refrigerant to leaks. With a lower amount of refrigerant in the evaporator coil, the coil will draw less heat, and the remaining refrigerant will stay too cold.
Evaporator Coil Ice
Occasionally, the evaporator coil of a wine cellar cooling unit may ice up. This can happen for several reasons.
Preventing Coil Ice
Customers can help ensure that their self-contained units will not develop ice on their evaporator coils. By ensuring that their unit has at least three feet of clearance on all sides (five feet is ideal), customers can prevent supply air from recirculating. This will go a long way towards preventing coil ice.
Conclusion
To conclude, both poor installation and improper charging procedure can cause coil ice to form. To prevent damage to your unit and wine cellar, make sure your self-contained unit has adequate ventilation. Decorative grilles and other objects can obstruct airflow and cause ice to form on the evaporator coil.
What causes the icing of the evaporator
i am having a problem with at least 3 cold rooms icing the evaporator coils. All i need is a long term solution to my problem.
Re: What causes the icing of the evaporator
hi rodney, when you say icing, what does it look like? is it the snowy fluffy stuff that might indicate poor door seals or broken insulation, or is it the hard stuff that could indicate poor defrost or blocked drain. incorrect gas charge can also cause icing.
Re: What causes the icing of the evaporator
So does leaving the door open. Our biggest icing up problem in supermarket coldrooms used to be that the damn staff would NOT close the door behind them! ;-)
Re: What causes the icing of the evaporator
If you are using a defrost timer to achieve a defrost, what is the duration of the defrost and the period between defrosts?
Re: What causes the icing of the evaporator
Do the evaporators have heaters? Heaters are not usually fitted in cold room applications.
Re: What causes the icing of the evaporator
Aiyub, With the low room temperature and generally low ambient you guys experience defrost heaters are necessary.Rodney is from Zimbabwe, a country with tropical weather. Thanks for that bit of info though. It seems like Rodney is not going to reply to us, maybe he has power problems amongst other. Feeze.
need of text books
Can anyone supply me with text books that suit the tropical whether here in zimbabwe. Am sitting for december exams {UK BASED EXAMS}, a diploma in refrigeration. Thats the main resean why i need text books
What Causes an Air Conditioner to Ice Up?
The sight of ice on an air conditioner unit may appear strange, but in fact it points to a common problem with HVAC systems. It occurs when an element of the condenser is not getting enough hot air coming in to keep the proper temperature, which leads to freezing.
Fixing an Air Conditioner Freezing Up
Changing the air handler filter or return air filter may fix the problem. Turn off and unplug the A/C unit before changing a filter or attempting any other type of repair. Removing any obstruction to airflow (curtains, blinds, etc.) is another practical step for you to take when you find your A/C freezing.
Why Frost or Ice Forms on an Evaporator Coil
Frost line on the cooling coil: When liquid refrigerant enters the evaporator coil temperatures may be as low as 10 degF at that point - that is at the top of the coil at the point of refrigerant entry.
Photo of an iced-up cooling coil courtesy of Bill McNeill
The air flow is too slow or has completely halted across the cooling coil. The cause of this problem could be as simple as a dirty air filter or it could be crimped, disconnected ductwork or even improperly-sized ductwork.
Reader Q&A - also see the FAQs series linked-to below
On 2020-11-15 by (mod) - how much refrigerant loss before we see a malfunction ?
Reader Question: poor cooling traced to iced coil traced to dirty air filter
Our problem began with a poorly performing unit. The Ice only formed after the visit by a licensed hvac tech recommended by our ins. co. who wanted to install a completely new system.
Question: will a wet air filter block airflow and cause coil icing?
If air filter gets wet does it block air flow causing frost to build up on coils?
Reader Question: Low Refrigerant & Coil Icing: cooling coil icing & bubbles in the refrigerant sight glass
Hi, AC just stopped cooling (2 year compressor / condenser unit). Tech said freon very low. Charged system with 6 lbs of R22, checked quickly for obvious leaks and left. The site glass indicator had a solid flow of Freon with micro bubbles. Noticed that the larger suction line never got cold. The smaller liquid line was warm for a short while.
Reader Comment: control board error may cause cooling coil icing
Another cause of icing is the control board not sending the signal to the compressor to shut down meanwhile the blower has soppped and the louvers has closed. Replace the control board or install a new seperate thermostat
What is an evaporator coil?
The evaporator coil of your air conditioner is one of the primary components in the heat exchange process, which allows your system to heat and cool your home. As your AC unit pulls in the warm air from your home, it passes this air over the evaporator coils.
6 Causes of a Frozen Evaporator Coil
As stated above, the evaporator coils work by absorbing heat from the air. But if they don’t have enough heat to absorb, the condensation on the coils can freeze. Low airflow can be caused by dozens of problems within the AC system, such as a malfunctioning blower fan, dirty air filters, or even damaged ductwork.
How to Fix a Frozen Evaporator Coil
While many evaporator coil problems will require professional inspection and repair, there are some things you can do on your own.
How Preventative Maintenance Can Help
While regular wear and tear is part of any AC unit’s lifespan, preventative maintenance is one of the most effective ways to ensure your system is working properly.
If You Need to AC Repairs, We Can Help
At Complete Air Mechanical, we have experienced HVAC professionals who can inspect and repair your air conditioner. We provide services in Orange, Osceola, Seminole, and Volusia counties, and we offer financing options.
