AC Not Blowing Cold Air After Rain, What to Check?

In the absolute majority of cases, rain won’t cause any damage to your cooling equipment. However, there can be exceptions.

Your AC will stop blowing cold air after a rain if the evaporator coil freezes, if the system had bare wires, or if your outdoor unit got clogged with debris. Do bear in mind that you’ll feel warmer as the humidity level rises, so your AC might actually be fine.

AC Not Blowing Cold Air After Rain, What to Check?

  • It might be the high humidity that is making you think that the AC is not blowing cold air. The more moisture there is in the air, the warmer your body is going to feel. Check the temperature of the air inside the house – the air conditioner might be reaching the same temperature, as usual, it’s just that it is going to feel warmer.
  • An AC not blowing cold air after rain might also be a wiring issue. If you have a damaged or bare wire somewhere in the system, it might get affected by the water. Turn the power to the unit off and inspect the cables.
  • The evaporator coil might be freezing up during rain as the water is acting as an additional heat transfer medium. In such a case, make sure that the coil is clean and turn on the fan every time it starts raining.
  • Sometimes strong wind might be the issue. If debris gets stuck in the outdoor unit, the air conditioner might stop cooling the air. Check the outdoor unit to make sure that it’s clean and that nothing’s stuck inside.

Why AC Is Not Cooling in Rainy Season?

You might end up lowering your thermostat during the rainy season, as it may feel as if your AC is not able to cool the space effectively. In a lot of cases, the cooling capacity of the unit stays the same, the thing that changes is how we perceive temperature when the humidity level is high.

To make sure that your air conditioner doesn’t overwork, switch it to dry mode or start running a dehumidifier.

Read: Why HVAC Damper Keeps Getting Stuck Closed?

Why Is My AC Not Working After It Rained?

  • An electrical surge might have caused damage to the unit. A tripped breaker is an easy fix, but, unfortunately, power surges can damage the capacitor or the compressor (in such a case, your unit won’t be able to operate).
  • During heavy rainfall, your outdoor unit can get clogged with twigs, leaves, and dirt. The AC might not be able to function until you clean the outdoor unit or the equipment can get damaged altogether (if a branch falls on the outside part of the system, for example).

Can Water Damage Your AC Unit?

Water can’t really cause damage to an air conditioning unit. This kind of equipment is designed to be able to survive even relatively heavy rainfall as all the electrical components are sealed inside the system.

However, the AC unit can get damaged, if it gets covered by water during a flood.

Read: How To Tell If HVAC Zone Damper Is Normally Closed Or Normally Open? 

Can AC Be Damaged by Rain?

It is not the water that can cause damage to the unit, it’s the winds and power surges that heavy rains are often accompanied by that possess a danger to your air conditioning system.

Objects can fall onto the outdoor unit or it can get clogged with debris. Voltage surges can occur during lightning or after power outages and they, in their turn, can affect the electric components. 

How Do You Get Rain Water Out of an Air Conditioner?

If water stays inside the air conditioner for long enough, it can lead to corrosion. That’s why it’s important to make sure that the unit’s drain hole is not blocked by leaves or dirt.

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If you have a window air conditioner, then tilt the unit slightly back. This will allow the water to drain instead of getting collected in the lower base.

How Do I Protect My Outside AC Unit from Rain?

You don’t really need to protect your AC from rain, but you might want to find a way to keep the debris away from your unit.

Special air conditioner covers can be used to protect the outdoor unit. However, do bear in mind that you cannot use the air-con if you’ve got the unit covered.

Read: Why HVAC Zone Damper Actuator Making A Clicking Noise? How To Troubleshoot?

What Happens to Window AC When It Rains?

Under normal circumstances, rain won’t be able to cause damage to the cooling equipment, even if it gets inside the unit – all the electrical components are insulated from water.

But if the water doesn’t get drained from the unit, then it can end up damaging some of the AC’s parts. If the draining hole is blocked, then the rainwater that made its way inside the unit can cause corrosion.

If the unit gets flooded, then the electrical components and the moving parts will, most likely, get damaged.

Do You Have to Cover AC in Rain?

You should not cover the air conditioner with a garbage bag or plastic wraps as the moisture from the condensation will stay inside and this can potentially make the metal parts corrode.

How Do I Cover My Outside AC Unit?

If you’re planning on covering your outside unit during a storm, then you will be left with a few options:

  • You can cover the unit with a tarp that will withstand strong winds
  • You can place a plywood or metal cage around the unit to protect it from leaves, twigs, and debris
  • Or you can always choose to buy a special AC cover that is designed to protect the outdoor unit during bad weather

How Do I Protect My Air Conditioner from Flooding?

  • Install a higher concrete base
  • If you placed the cooling unit in the basement or on the ground floor, consider relocating it to the attic or the second floor
  • Build a wall around the HVAC unit
  • Install a pump in the basement to prevent indoor flooding

Read: Should An HVAC Zone Damper Bleed Air?

What Happens If an AC Unit Floods?

An AC that has been flooded can stop blowing cold air or working altogether as the electrical components and the moving parts will most likely get severely damaged.

If the water has reached around 15 inches in depth, then the chances are extremely high that your unit got affected.

How Can You Tell If AC Has Been Struck by Lightning?

If your air conditioner got struck by a lightning, you will see visual evidence of arcing and charring of the casing. Moreover, not one but multiple components in the system will be damaged (for example, the motor, contactor, capacitor, and compressor). 

How Do You Fix an AC After Lightning?

You can try resetting the unit at the breakers, but unfortunately in the majority of cases, a lightning strike would make your AC pretty much unusable.

Can a Storm Cause AC Not to Work?

There are a few things that can possess a danger to your AC equipment during a storm:

  • Strong winds
  • Lightning and power surges
  • Potential floods

Read: How Reliable Multi-Zone HVAC Systems Are?

What to Check If AC Is Not Cooling?

  • Check thermostat settings
  • Replace the clogged filter
  • Clean the condensation drain
  • Clean the coils
  • Clear the area around the outdoor unit

What Happens If Water Gets in Air Ducts?

Any kind of moisture trapped in the ducts can lead to mold growth.