Q. We purchased a used modular deck oven, but do not know how to operate the steam generation. The oven has new control panels on both the side and front. It has a timer but we don’t know how to operate it. Can you offer any tips to make the steam generator operational?
Adrianna, via email
A. Your particular oven model is manufactured in Spain, and has no sales or service connections in North America. The steam is produced in a separate chamber fitted with electric heating elements. To try to find the problem, turn the power off, drain the chamber of any water and remove the elements. Flush the chamber with water until clean. If the elements are cracked or broken, they need to be replaced. Your electrician can check these for continuity. Be careful not to supply energy to the elements until they are submerged in water in the chamber.
The water supply to and from the generator may be controlled by solenoids, which are electrically controlled valves. These should be inspected. Over time, excess buildup of mineral deposits can clog them and any deposits need to be removed. The solenoids have a gasket, pin and spring inside that also should be inspected; however, I recommend replacing the old parts inside with new as gaskets can wear and begin to leak. If the gasket leaves a black film on your fingers when you touch it, you need to replace it. It also is wise to install a water filter and regulator. Test your water to determine what type of filter is necessary for your needs.
Since the wiring and panel have been changed from the original, it will be difficult to repair, even with schematics, since they may be obsolete. However, from the photos you supplied me, I can see that the top two decks have heat and steam, and the bottom deck is heat only. The controls for the top two decks have several buttons. The top section controls the oven temperature, and the middle section controls the steam. The on/off switch starts heating the water, and the start button releases the steam into the oven. Your oven has a dial to regulate the amount of steam; some ovens’ steam flow is manually controlled by pressing a button or opening a valve.
Once these controls are established, your electrician can start at the power source and trace these controls. Some of this will be trial and error, considering the changes made to the oven’s panels.
Q. We have an 80-qt. planetary mixer that has trouble raising and lowering the mixing bowls. Any suggestions?
Joel, via email
A: A long spindle raises and lowers the bowls, and it stretches from the top of the machine to the plate that the bowls mount to. When the lever to raise and lower the bowls is actuated, the spindle turns clockwise or counter clockwise accordingly, and the bowl plate follows up and down the spindle. Two guide bars are situated on both sides of the machine that the plate also travels on. These need to be lubricated periodically. They are located behind an access plate on the front of the machine. Remove the plate–usually a few screws holds it on–to access the spindle and guide bars. Apply a lubricant to the spindle and guide bars; I prefer to use lithium or moly grease on these parts because of their durability. Some of the models have access ports on top of the guide bars to allow use of a light motor oil to lubricate them.
If the problem still is present after the lube, then the trouble could be more mechanically located in the gearbox, and you should call for service.
Q. We are considering replacing an old deck oven with a new one. Do you recommend thermal ovens?
Ken, via email
A. In a traditional convection oven, the burner heats air and this heated air is then circulated throughout the oven decks. That circulated air heats the stone or steel decks. A cyclothermic oven, or thermal, heats oil that circulates throughout the decks. This thermal heating is available in both deck and rack ovens. The heated oil supplies a gentle radiating heat transfer and a fast recovery time between bakes. The benefits include even heat distribution with no hot spots on the decks, and they are highly efficient, usually with a 90 percent or higher rating. The newer ovens are highly insulated and supply a saturating steam that will produce quality products.
These ovens are more expensive than a convection oven, due to the lack of an internal burner. Thermal ovens have a separate burner that heats a large amount of oil, circulates it to the oven via stainless piping and back to the burner. If you purchase one, you need to ensure you have space for both the oven and the burner, which should be located in a separate room if possible. Good heat retention makes them highly efficient and perfect for baking hearth breads. However, these ovens take a long time to cool down. If your bakery needs an oven that can regulate the temperature up and down in the same day, a thermal oven may not be for you. One burner can supply heated oil to multiple ovens.
Have questions about how to keep your bakery equipment running efficiently or what type of equipment is best for your operation? Ask Keith Grant, Modern Baking’s Toolbox editor. Send your bakery equipment-related questions to firstname.lastname@example.org. Keith Grant is the production manager for Deising’s Bakery, Kingston, N.Y.