Technical Support FAQ

Whenever it comes to volatile gases and compounds, the gas pressure and volume are extremely important to ensure the system operates safely and properly. The incoming gas pressure to the valve train should never exceed the maximum allowable pressure of the valve train regulator. These pressures can be located on the manufacturer’s control panel door and can also be provided on the regulator by the manufacturer.

Pressures at the inlet of the valve that exceed this rating can cause damage to the regulator and internal components of the valve train. In some cases, resulting in the valve train failing to block the flow of gas even when the system is shutdown, resulting in an extremely dangerous situation of explosion and fire. The minimum gas pressure for the system is particularly important as well to ensure that there is enough gas pressure through the valve train and into the burner. Lack of gas pressure will cause issues with the BTU output of the burner and in extreme cases will cause the safety switches on the valve train that monitor low gas pressure to fault.

Typical oven pressure ranges are 2 to 5 PSI and typical Air Make-up Unit gas ranges are from 1.5 to 2.5 PSI but can change based on project designs and field requirements, check the drawings and manuals for exact ranges.

This is typically caused by excessive incoming gas pressure affecting system balance.

When gas pressure exceeds regulator ratings:
• Airflow and burner output become unstable
• The system may create positive pressure inside the booth
• Doors can blow open due to improper pressure differential

Check the valve train regulator, system gas pressure, and follow the manufacturer’s recommended pressure ranges.

A: The control panel is equipped with a “Fan Speed” knob on the door. Adjust the knob to a higher value for more airflow, or a lower value for less airflow.

A: When it comes to determining when to change your spray booth filters, first we must differentiate between intake filters and exhaust filters. Intake filters are located where the outside or shop air is introduced to the spray booth working environment. These filters work to ensure that the air introduced into the spray booth is free from debris, which can cause defects in your coatings. Exhaust filters are in separate locations, depending on the design and construction of your spray booth. The primary function of these filters is to capture overspray from the booth working environment and prevent harmful and hazardous particulates from being exhausted into the atmosphere by the booth exhaust fans. The function of both filter types is paramount to the spray booth functioning properly and ensuring the best possible coating finish. Spray booths are designed to meet National Standards, such as OSHA and the NFPA. When filter maintenance is neglected, the performance of the spray booth will fall below the standards’ requirements. When the spray booth performs below the designed param¬eters, proper airflow will not be present and the likelihood of overspray or dust to accumulate on the coated part increases exponentially. Because there are many different filter constructions available, it is difficult to mandate a certain time interval for filter change outs. There are many other factors that play a part in the life span of the filters, including cleanliness of the surrounding environment, type of coating being sprayed, application styles and equipment used, spray booth air speed, spray booth design and construction and design of the filters can all affect the life of the filter. However, there are some key indicators that your filters are coming to the end of their effective life span:

Intake Filters:
When an increase in debris or dust is noticed in the booth or in the coatings.
If you have a manometer or Magnehelic gauge to measure pressure, drop through the filter, change at the suggested loading of the manufacturer.
Filters have been installed for six months.

Exhaust Filters:
When overspray is noticed to be lingering in the booth more than usual.

The spray booth fan is operating at 100% capacity.

If you have a manometer or Magnehelic gauge to measure pressure, drop through the filter, change at the suggested loading of the manufacturer.

Applying a coating that is capable of spontaneous combustion or other harmful compounds.

Filters have been installed for one month.

It is best practice to establish a filter maintenance program with the help of RTT Engineered Solutions. Improper filter maintenance can affect more than just the finished coating. It can also affect the health and safety of your employees as well as the profitability of your business.

RTT recommends that the temperature probe be in the discharge ductwork of the Air Make-up Unit (AMU). The probe is to be located as far from the discharge location of the AMU as possible before entering the paint booth intake plenum. This configuration helps to avoid sharp spikes in temperature and will even out the ramp and soak time of the burner. Eliminating the possibility of an over-temperature situation inside the AMU. In rare instances, the temperature probe may be in the intake plenum of the spray booth. Please consult with RTT Technical Support before locating the temperature probe anywhere other than the AMU discharge ductwork.

The oven temperature probe is located as a standard design between the return air of the heater box and the exhaust fan of the oven. During the initial commissioning of the oven, RTT recommends using a separate device capable of recording temperatures within the oven (such as a DataPaq) to compare the oven temperature probe to actual temperatures within the oven It may be possible after evaluating the testing report the probe location may need to be changed to better read the average air temperature of the oven.

CT/CTC AMU – All passcodes provided in the RTT Booth & AMU Detailed Start-up Guide).

Operator passcode is 2050
Oven – All passcodes in the Oven Operation & Maintenance manual. Maintenance passcode is 1111

The life cycle of any filter has many factors that directly affect its lifespan. These factors include moisture, housekeeping procedures, velocity of air traveling through the filter, type of media being filtered and environment. The 80/20 cellulose cartridge filters supplied by RTT for your equipment is expected to be in operation from 3-12 months depending on these factors.

There could be several issues that could cause your exhaust fan not to operate. If you have confirmed you have power, do you have a fault on your Variable Frequency Drive (VFD)? Check to see if there is a fault code displayed on the VFD. Depending on the make and model of your VFD these codes can differ.

All air make-up units provided by RTT Engineered Solution can heat the air in spray mode but only to a limited temperature. All that is required is for the booth controller to be set to WINTER mode. This will allow for the AMU to ignite the burner even in spray mode.

This typically indicates a failed air switch.

Your system uses air switches on the combustion fan, recirculation fan, and exhaust fan.
If one of these switches does not provide airflow, the system returns to purge for safety.

Temperature overshoot commonly relates to the burner actuator not opening correctly. Check the following:

• Confirm the actuator shaft markings to verify it is opening 100% after ignition.
• Ensure all linkages and set screws are tight. Over time, set screws may loosen, allowing the actuator to turn without fully turning the shaft.

Your oven should operate with gas pressure between 2 PSI and 5 PSI.
Pressures outside this range may affect burner performance or safety.

The “H” slots must be opened at least 1.5 inches to maintain proper airflow and system balance.

You can download temperature history directly from the Smart Control panel:

1. Open the Maintenance tab
2. Select Temperature History
3. Click Export
4. Follow the on-screen instructions to save the file

Proper gas pressure is critical for safe and reliable operation.

• Gas pressure must never exceed the maximum rating of the valve train regulator.
• Excess pressure can damage internal components or prevent the valve train from shutting off gas during a shutdown, creating a serious safety hazard.
• Too little pressure reduces burner BTU output and may cause low-gas safety faults.

Typical pressure ranges:
• Ovens: 2–5 PSI

RTT recommends placing the temperature probe in the AMU discharge ductwork, as far from the discharge point as possible before the air enters the paint booth intake plenum.

This placement:
• Prevents temperature spikes
• Ensures accurate temperature control
• Minimizes risk of over-temperature conditions inside the AMU

In rare situations, the sensor may be placed in the booth intake plenum. Contact RTT Technical Support before doing so.

Yes, proper gas pressure is critical for safe and reliable operation.

• Gas pressure must never exceed the maximum rating of the valve train regulator.
• Excess pressure can damage internal components or prevent the valve train from shutting off gas during a shutdown, creating a serious safety hazard.
• Too little pressure reduces burner BTU output and may cause low-gas safety faults.

Typical pressure ranges:
• AMUs: 1.5–2.5 PSI (varies by design; refer to drawings/manuals)
• Ovens: 2–5 PSI