The Heat Injector being used as Heated Air Makeup

The Heat Injector Service Team has done a Fantastic Job installing the 1.5Million BTU Heat Injector on the 40ft x 16ft large equipment spray booth from Global Finishing Solutions.

The spray booth will be used for painting JLG equipment that is used on construction sites throughout the country.

There were a few modifications that had to be made to the spray booth design to allow the Heat Injector to be installed on the fresh air supply of the spray booth.  The Supply end of the spray booth had to be reinforced with support beams to hold the load of the 42″ fan/motor, the Heat Injector duct heater, and the supply ductwork that doubled as an injection chamber for the Heater. The Heat Injector is a patented product that utilizes a dedicated combustion blower that allows for a variable airflow across the burner.

Here are some pictures of the raised supply plenum and the rails that span from beam to beam. The rails will support the supply ductwork and the Heat Injector.

Because of the patented dedicated combustion blower on the Heat Injector  – The Heat Injector can be installed upstream of the fan controlled by a VFD.  The Heat Injector is enabled by an intake temperature and is able to control the heated output at any speed of the fan without dampers or motorized profile plates.

In the below images you can see how little static the Heat Injector adds to the airflow system while supply  1,500,000BTU of clean controlled heat.

The left image is the 480v Main Disconnect with the supply and exhaust VFD’s.  The right image is the spray booth control panel that has the Heat Injector controls, System airflow controls, the booth light switch. Once the outside air temperature is below the setpoint on the intake temperature controller the call for heat is enabled and the Heat Injector will either illuminate the green flame on or the red flame failure light. After the flame on light is on, the Heat Injector will PID control the Heater to produce the desired discharge temperature, which in this situation is about 75ºF.  This same system could also produce elevated temperatures of +140ºF if drying is needed.

The Direct Fired Heat Injector has several interlocks and a flame monitoring system all running at the same time. The Heat Injector is always monitoring the upstream and downstream high temp limits which are both manual resettable. The inlet gas pressure is monitored by a low gas pressure switch to make sure there is enough gas pressure and the regulated gas pressure is monitored by the high gas pressure switch to ensure the regulator is function normal. There is also redundant gas valves and visual indicator along with a proof of closure(POC) on the gas train. Once all those are approved to open the valves the system will not ignite unless the low fire position switch is not met and the system will not stay running unless the flame rod sensor does not indicate the flame is present.  All of these flame safeties are automatic once the heat enable is sent to the Heat Injector.

This video a brief explanation of the Heat Injectors operation by Kevin Krupp.

This video a brief explanation of the overall spray booth operations by David Krupp.