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Volvo Truck: Emissions & Climate Control Problems (Solved!)

One thing that sets up the vibe when you are driving is the emissions and climate control systems. 

If you constantly have problems with the emissions and climate control systems, you will feel wary of your road performance. 

A malfunctioning climate control system may result in an uncomfortable journey. It can also affect your driving focus which might lead to unwanted accidents. 

As an advocate for road safety, we have collated all the problems you may encounter regarding emissions and climate control. Read on further to find out more. 

A Short Summary of Common Volvo Truck Climate Control Problems to Expect:

Typical Volvo truck climate control problems are AC blowing hot air due to refrigerant leak, overworked compressor, or blocked condenser. Heater issues such as a defective fan or thermostat, contaminated coolant, or low radiator water levels also affect a Volvo truck’s climate control performance.

Volvo Truck Climate Control Problem

Volvo trucks are equipped with either electronic or manual climate control systems. 

The auto climate control system allows a hand-free temperature regulator. It automatically sets AC, fan speed, air distribution, and recirculation. Once you select a temperature, the truck will maintain temperature regardless of what is happening inside the vehicle.

The manual climate control system works similarly, but truckers must set up the settings manually. Unlike its auto-climate counterpart, you may need a switch or control knob to adjust the climate control system.

Due to wear and tear or improper handling, these systems may experience issues or, worse, not function. 

Some common problems that the Volvo climate control system may experience include:

  • Damage to AC is due to a leaking refrigerant, overworked compressor, or blocked condenser
  • AC blowing hot air
  • Heater problems 
  • Damaged diesel exhaust fluid (DEF)
  • Engine Gas Recirculation (EGR) issues
  • Nitrogen Oxide (NOx) Sensor problems
  • Regeneration problems

Volvo Truck Air Conditioning Problems

The AC in a Volvo truck is damaged or has problems when hot air blows in the cabin, has low air pressure, foul odors linger, leaks or stains, or produces strange noises.

Make sure to address all these issues before the AC becomes completely damaged or to prevent significant repairs.

Most of the time, the primary perpetrators of AC problems include a leaking refrigerant, an overworked compressor, or a blocked condenser

  • Leaking refrigerant

The compressor cools the refrigerant and sustains air movement in the truck. Its performance depreciates due to holes or problems with the hose. Metal corrosion or poor installation causes the refrigerant hoses to have issues. 

To resolve this problem, follow these steps:

Step 1: Assess if the hose is repairable by applying patches. If not, replace the hose immediately. 

Step 2: If no holes are visible, maybe the problem is with the hose fitting. Just tighten the fitting and see the difference. 

  • Overworked compressor

The compressor is designed to process gas only. Now, if the air conditioner sips in other particles like dust, dirt, or water, it will result in an overworked compressor. 

A simple cleaning routine with the air conditioner filters will do to fix the issue. 

  • Blocked condenser

Since the condenser is located at the front of the truck, it gets dirty over time. The debris that its grill catches is the cause of the malfunctions in the condenser. 

Make sure to check the condenser for any debris and remove them immediately to avoid further damage. 

Volvo Truck AC Blowing Hot Air

Refrigerant leaks, faulty condenser and compressor, and faulty electrical systems can cause AC to blow hot air. Fix these issues immediately to avoid further damage.

  • Refrigerant leaks

Nothing in the AC components will work with improper refrigerant levels. Leaks are caused by cracks or holes in coils. 

If the cracks or holes are insignificant, you can patch them to hold the refrigerant fluids. 

Replace the coils if patches won’t hold them well. 

  • Faulty condenser 

The condenser fails to work correctly due to debris that clogs it. A good clean-up will do the trick. 

  • Faulty electrical system

Do an ocular inspection on the fuse and wirings to see any irregularities. If the fuse is blown, replace it right away. 

Volvo Truck Heater Problem

Volvo truck heaters may fail to perform well because of low water levels in the radiators, failing thermostats, malfunctioning blower or fan, and coolant with many dust particles.

Each of these parts has its repair guides that you can follow.

  •  Low water level in radiators.

The leading cause why the radiator runs low on water is leaking in the cooling system. You can fix this by adding pre-mixed coolant or a 50-50 solution of coolant and water. Only add water during emergencies but not regularly. 

  • Failing thermostats

The three reasons why your truck thermostat fails are too much use of hot and cold settings or a sporadic change in the temperature. 

To replace your thermostat, follow these steps:

Step 1: Remove the old thermostat near the top of the engine. 

Step 2: Clean the mating surfaces.

Step 3: Install the new thermostat.  

  • Malfunctioning blower or fan

Blower or fan problems are caused by motor failure. Your truck fan motor may fail if the fuse is blown. Replace its corresponding fuse to fix the issue.

  • Dusty Coolant

You can fix a dusty coolant with the following steps:

Step 1: Drain the coolant. 

Step 2: Fill the radiator with water. Once the engine has cooled, drain the water.

Step 3: Flush the cooling system 2 to 3 times, then refill with coolant mixture. 

Volvo 670 Bunk Heater not Working

A common problem with the bunk heater is that it either works partially or doesn’t function completely. To fix the issue, follow these helpful guides.

  • Vents are blowing at the bottom only.

The vents of a bunker heater are usually at the bottom of the bunker. This is because hot air is light and rises in the area over time. But if it does not heat the whole bunker, there is a problem. 

You can opt to change the angle of the vents so that they can reach out to other directions or parts of the bunker. 

You can also check the fuel pump as it may not work correctly due to clogs. 

  • The heater completely shuts off after an hour or two.

If this happens, you must check fuses F1 to F7. If one of those fuses is blown or not working, replace it. 

Volvo FH Night Heater not Working

A truck heater is essential on the road during the cold seasons. But it is also prone to a lot of problems over time. 

Here are possible causes and fixes for a Volvo FH night heater not working.

  • Low engine coolant

If your Volvo truck doesn’t have enough coolant, it will fail to provide heat to the heating system. This situation commonly occurs when a truck has a low engine coolant. 

You can fix it by filling up the engine coolant. Also, check if there is a coolant leak. Failure to check the coolant will lead to a costly repair in the future.

  • Malfunctioning thermostat

A malfunctioning thermostat also affects how the coolant flows. This means the coolant will stay cold as it will keep circulation on the radiator. 

Fix this issue by replacing the thermostat. After all, a thermostat is not expensive nor difficult to install.

  • Aging heater core

The heater core will break because of wear and tear. Most often, there is a problem with the passageways that prevent the heater from giving out heat. 

Fix this issue by cleaning up or replacing the coolant. There might be dust or debris that clogs the passage.

  • Radiator leaks

Coolant passed through several parts of the Volvo truck’s engine. Any leak from those places is an added factor why the heater does not work.

If the radiator leaks, the coolant level will get very low. Repair this issue by replacing the radiator with a new one. If the problem is already severe, hire a mechanic to do the work.

Volvo Truck DEF Problems

Volvo has found that truck owners have been experiencing the same problems with their diesel exhaust fluid or DEF.

They have constantly been getting calls about accidentally putting diesel fluid on the tank, DEF contamination, and improper handling. Volvo has now addressed these issues and provided a care routine to fix this. 

  • Fill confusion

To avoid getting confused with the filling holes, remember that the DEF fill hole is smaller than the fuel tank. 

  • Contamination

DEF fluid is highly prone to contamination. Make sure to avoid filling up the DEF without cleaning the exterior first. Also, ensure that you will clean the cap before closing it. 

The rust particles can get in quickly and unnoticeably. The fluid itself is susceptible to temperature changes. You must keep it out of sunlight.

Also, ensure that you will not store it in an area below 12 degrees Fahrenheit because the fuel may freeze. 

We suggest buying 2.5 gallons instead of bulk storage to avoid waste and mass contamination. 

Volvo Truck EGR Valve Problems

The symptoms of damaged Engine Gas Recirculation (EGR) are frequent stalling, increased fuel consumption, smelling of fuel, and knocking sounds. 

Check the spark plugs, wires, fuel filter, fuel pump regulator, or engine sensors to fix the issue. You can quickly resolve any issues within these parts by cleaning or replacing the damaged component. 

Volvo Truck NOx Sensor Problems

Nitrogen oxide or NOx sensors inform you about the amount of nitrogen oxide the truck produces. If it fails, the SCR system is affected since they are connected. 

Replacing the Nox sensors can fix the problem. It would be best to change the NOx emulator to ensure it will function in the long run. 

Volvo Truck Regeneration Problems

Regeneration of Diesel Particulate Filter Regen occurs when the DPF burns the accumulated soot to prevent clogging. The most common problem it encounters is blocked DPF. Scheduling a routine clean-up and maintenance will help avoid these problems. 

Regen failures have a lot of underlying reasons. It can be one of the following:

  • Blocked doser
  • Problematic turbocharger
  • Clogged DPF
  • Blocked DOC
  • Faulty DPF pressure and temperature sensors
  • EGR and Engine fault codes

The best thing to do is check them periodically and one at a time. Replace any part that has been damaged or clean those that are clogged or blocked with debris. 

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