Zephaire

Overview

Blodgett Zephaire ovens are commercial convection ovens for kitchens that need to bake or roast across multiple racks. The supplied documentation covers electric Zephaire E and E Plus operating controls, and provides separate specifications for the electric bakery-depth and gas bakery-depth configurations. These specifications should be read by configuration: pan capacity, heating system, electrical or gas requirements, dimensions and warranty details are not identical across the family.

The electric bakery-depth specification describes a porcelainized steel liner and a chamber that accepts five standard 18-inch by 26-inch bake pans. Its blower distributes air through the baking chamber, and its manual thermostat covers a 200°F to 500°F range. The gas bakery-depth specification describes a direct-fired system, electronic spark ignition, and a two-speed blower. Refer to the oven's rating plate and applicable documentation when identifying requirements for a specific unit.

Key Features

• Convection airflow: The documented electric model uses a single-inlet blower wheel powered by a two-speed motor; the documented gas model uses a single-inlet blower wheel and a two-speed, 3/4 HP motor with automatic thermal overload protection.
• Full-size pan support: The bakery-depth specifications state that five 18-inch by 26-inch pans fit in left-to-right or front-to-back positions.
• Rack access: The bakery-depth gas specification lists five removable chrome-plated racks and eleven rack positions. The electric specification lists five removable chrome-plated racks.
• Controls: Depending on the documented configuration, controls include a Cook/Cool Down selector, thermostat and 60-minute timer. The Zephaire E Plus manual also describes cavity lights, a high/low blower switch and, on an optional spritzer control, a water spritzer.
• Door options and operation: The bakery-depth gas specification describes dual-pane thermal glass windows, a powder-coated handle and simultaneous door operation; solid stainless-steel doors are also listed as an option. The electric specification describes dual-pane thermal glass windows and simultaneous operation.

Specifications

• Product type: Commercial convection oven.
• Electric bakery-depth configuration: Porcelainized steel liner; capacity of five standard 18-inch by 26-inch bake pans, positioned left-to-right or front-to-back; five chrome-plated removable racks; three tubular heaters; single-inlet blower wheel; two-speed, 1/3 HP motor with thermal overload protection; recessed control panel; Cook/Cool Down selector; solid-state manual infinite thermostat from 200°F to 500°F; 60-minute timer.
• Electric bakery-depth power supply: 208 V, 60 Hz, single-phase, 11 kW, 51/0/51 A; 208 V, 60 Hz, three-phase, 11 kW, 31/29/29 A; 220/240 V, 60 Hz, single-phase, 11 kW, 44/0/44 A; 220/240 V, 60 Hz, three-phase, 11 kW, 26/24/24 A; 440 V, 60 Hz, three-phase, 11 kW, 15/14/14 A; or 480 V, 60 Hz, three-phase, 11 kW, 14/13/13 A. Motor: 1/3 HP, two-speed, 1140 and 1725 RPM at 60 Hz.
• Electric bakery-depth shipping details: Approximate oven weight 545 lb (247 kg). The listed crate size for each section is 37-1/2 inches by 43-1/2 inches by 52 inches.
• Gas bakery-depth configuration: Full-size bakery-depth baking compartment; capacity of five standard 18-inch by 26-inch pans, positioned left-to-right or front-to-back; porcelainized/stainless steel liner; five chrome-plated removable racks; eleven rack positions with minimum 1-5/8-inch spacing; stainless-steel front, top and sides; double-pane thermal glass windows in stainless-steel door frames; single powder-coated handle with simultaneous door operation; two halogen lamps per chamber; direct-fired gas system; electronic spark ignition; removable inshot burners; internal pressure regulator; front-panel manual gas service cut-off switch; solid-state thermostat from 200°F to 500°F; two-speed fan motor; 3/4 HP blower motor with automatic thermal overload protection; control-area cooling fan.
• Gas bakery-depth dimensions: Floor space 38-1/4 inches wide by 36-7/8 inches deep. Interior 29 inches wide by 20 inches high by 28-1/4 inches deep. For the listed caster configuration, add 4-1/2 inches to single-oven height; double-oven height remains the same. For the listed double low-profile configuration, subtract 2.5 inches from height dimensions.
• Gas bakery-depth access and shipping: Minimum entry clearance is 32-1/16 inches uncrated and 37-1/2 inches crated. Approximate weight is 590 lb for a single oven and 1,095 lb for a double oven. Crate size is 37-1/2 inches by 43-1/2 inches by 51-3/4 inches; two crates are required for a double oven.
• Gas supply: 3/4-inch NPT inlet. Natural gas inlet pressure: 7.0 inches W.C. minimum to 10.5 inches W.C. maximum; manifold pressure: 3.5 inches W.C. Propane inlet pressure: 11.0 inches W.C. minimum to 13.0 inches W.C. maximum; manifold pressure: 10 inches W.C. Maximum input: 50,000 BTU/hr (14.6 kW) per oven section.
• Gas-model electrical supply: 115 VAC, single-phase, 8 A, 60 Hz, 2-wire with ground, with a 3/4 HP, two-speed motor at 1120 and 1680 RPM; a 6-foot electric cord set is furnished on 115 VAC ovens. The specification also lists a 230 V, single-phase, 3 A, 50 Hz model with a 1/2 HP, two-speed motor at 1440/930 RPM.
• Documented warranties: The electric bakery-depth specification lists 1 year parts and 1 year labor, plus a 3-year limited door warranty. The gas bakery-depth specification lists 2 years parts and labor, plus a 3-year limited oven door warranty. Confirm warranty coverage for the specific oven and market.
• Operator-manual details: The supplied Zephaire E manual gives a 200°F to 500°F thermostat range and says its oven holds up to ten 18-inch by 26-inch bun pans. This capacity is from that manual and is not the five-pan capacity listed for the bakery-depth configurations above.

Installation & Requirements

Electric connection and placement

The operator manual states that the rating plate is attached to the back of the oven body. Check it against the electrical service before making utility connections. For the electric oven covered by that manual, the service line enters through the rear and connects to the terminal block: remove the bottom trim and control panel, route the supply line through the rear knockout, connect the wires to the terminal block, then reinstall the control panel and trim. Installation and service are for qualified personnel. The manual directs US and Canadian installations to follow local codes, or, where local codes are absent, the latest National Electrical Code ANSI/NFPA 70 and/or Canadian National Electrical Code C22.2 as applicable.

The electric operator manual specifies 1/2-inch clearance at the oven body's right side, left side, back and bottom. It also calls for adequate access for servicing, keeping combustibles such as paper, cardboard, flammable liquids and solvents clear of the oven area, and not placing the oven on a curb base or sealing it to a wall, which would restrict airflow and ventilation. These placement instructions come from the electric operator manual; check the documentation for the exact configuration being installed.

Gas connection

The gas bakery-depth specification lists a 3/4-inch NPT gas inlet, inlet and manifold pressures for natural gas and propane, and a maximum input of 50,000 BTU/hr (14.6 kW) per oven section. Gas connection must match the oven's fuel type and rating information. The gas specification lists a manual gas service cut-off switch on the front of the control panel and describes the oven as direct-fired with electronic spark ignition.

Optional water spritzer

The Zephaire E Plus manual describes an optional water spritzer. For that option, it specifies a 3/4-inch female garden-hose connection at the rear of the oven and says the installation must include backflow protection in accordance with applicable codes. The spritzer is available on the manual's stated E Plus standard-control configuration; it is not a standard feature of every Zephaire.

Operation

Controls and starting the oven

Controls differ by version. The Zephaire E standard control uses a blower on/off switch, cool-down switch, oven-ready light, thermostat, cook timer and heat cutoff. The E Plus standard control adds cavity-light switching and a high/low/off blower switch. Its optional spritzer control adds a water-spritzer button and indicator. On the manual's standard control, the oven-ready light indicates that the elements are heating; when the light goes out, the oven has reached operating temperature.

For the electric manual's operating sequence, put the cool-down switch in AUTO, set the thermostat to the desired temperature and turn the blower on. Load the product when the oven-ready light goes out and set the cook timer. When the timer sounds, remove the product. To cool the oven for a lower-temperature next bake, the manual instructs the operator to use the cool-down mode with the door open. Turn the blower switch off to turn the oven off. The manual states that the fan must be operating for the oven to heat.

Cooking guidance

• Preheat before baking or roasting. The manual recommends preheating 50°F (28°C) above the cook temperature to offset the temperature drop when the doors open and cold product is loaded; for frozen product, it recommends 100°F (56°C) above cook temperature. Set the thermostat to the cook temperature after loading.
• As a starting point, the manual says convection-oven cook temperatures are generally 50°F (28°C) lower than deck- or range-oven recipes. If edges are done but the centre is raw, or colour varies, reduce the thermostat another 15°F to 25°F (10°C to 15°C) on successive loads until results improve.
• Check the product at about half the time given for deck- or range-oven recipes. Cook time varies with product quantity, pan type and temperature. The manual cautions that excessive temperatures do not reduce cook time and can produce unsatisfactory baking and roasting results.
• Centre pans on the rack and load from the bottom. Pan or product height determines rack use. The manual warns against placing a pan or aluminium foil on the oven bottom because it obstructs airflow and can cause uneven baking and roasting. Weigh product to distribute it evenly among pans.
• For light or liquid products, use Pulse Plus if that feature is fitted to help the product set and avoid rippling toward the fan. If it is not fitted, the manual gives an alternative: preheat 25°F (15°C) above baking temperature, load and close the doors, set the baking temperature, turn the oven off for 5 to 7 minutes so residual heat can set the product, then turn the oven on for the rest of the bake.
• For roasting, the manual suggests placing meat directly on the racks and putting a sheet pan half full of water in the bottom rack position. It says the water adds humidity as it evaporates and the pan catches grease. Turn oven lights off when not viewing product; the manual says leaving them on for extended periods considerably shortens bulb life.

Cleaning & Maintenance

The manual recommends routine cleaning and proper installation as the best preventative maintenance measures. For stainless steel, it describes wiping the cold oven with a cloth saturated with light oil, then drying it with a clean cloth. Baked-on splatter on stainless-steel fronts or interiors may be removed with a non-toxic industrial stainless-steel cleaner. Heat tint and heavy discolouration may be treated with a non-toxic commercial oven cleaner. Apply cleaners only when the oven is cold and rub with the grain of the metal.

Keep liquids away from light sockets, temperature probes and heating elements. Avoid spraying electrical connections, the thermostat and light-bulb receptacles. The porcelain interior may be cleaned with commercial oven cleaner; caustic cleaning compounds must not contact the aluminized-steel panel directly behind the blower wheel. The manual's cleaning directions also say to remove racks and rack supports and soak the parts in a solution of ammonia and water before reinstalling them. Disconnect power before servicing; the manual says unplugging is not necessary for cleaning.

The manual says the oven requires no lubrication. It calls for an annual check of the venting system for deterioration caused by moisture and corrosive flue products. For required maintenance or repairs, it recommends contacting a local Blodgett service company, factory representative or Blodgett Oven Company.

Troubleshooting

• Elements will not heat: The manual lists an unplugged oven, the control-panel power switch being off, the control being set below ambient temperature, or open doors as possible causes. Its suggested checks are to connect the electrical supply cord, set the control to COOK or OVEN ON, set the desired cook temperature and close the doors.
• Oven does not come to ready: It may not have reached preheat temperature; wait for preheating. The manual also lists an internal problem with the main temperature control and marks its remedy for qualified personnel.
• Convection fan does not run: The manual lists an unplugged oven, a tripped circuit breaker or open doors. Check the electrical connection, reset the breaker or close the doors.
• General baking problems: The manual lists a thermostat out of calibration as a possible cause and marks the remedy for qualified personnel.

The manual recommends that repairs or adjustments be performed by a local Blodgett service agency rather than the owner or operator. It warns that servicing by unqualified personnel can cause damage and directs users to disconnect the oven from power before servicing.

Applications

The manual includes suggested cooking temperatures and times for meats, poultry, fish and seafood, cheese dishes, potatoes and baked goods. Examples include roasting, baking pies and cakes, cooking poultry, and preparing sheet-pan products. Its tables are starting points only: the manual notes that actual times and temperatures vary with load weight, product temperature, recipe, pan type and thermostat calibration. Record proven settings for repeat production.