981

Overview

The Blodgett 981 is a commercial gas baking and roasting deck oven. It has two baking compartments, each 7 inches high, with a 42-inch-wide by 32-inch-deep cooking area. A 1-inch-thick deck provides a surface for baking pizza and bread directly, while other foods can be cooked in pans or containers. The two-compartment layout lets operators work with separate loads in the upper and lower chambers.

The 981 belongs to Blodgett’s 900 Series. Its controls use a manual gas valve, an automatic safety pilot valve and a thermostat. The safety pilot valve shuts off gas if the pilot goes out. The oven is gas-fired; the cited product information does not specify an electrical connection.

Key Features

• Two baking compartments: Each compartment measures 42 inches wide by 32 inches deep by 7 inches high.
• Deck construction: The product information specifies a 1-inch-thick steel deck. The 981/951 product listing also describes the deck as 12-gauge aluminized steel.
• Gas heat: The 981 is listed at 50,000 BTU per oven section for natural gas and propane.
• Counterbalanced doors: The 981 product listing identifies counterbalanced doors as a feature.
• Stainless exterior: The listed propane double-deck configuration identifies a stainless steel front, top, sides and back.
• Safety pilot: The 900 Series manual describes an automatic safety pilot valve that shuts off gas if the pilot fails.

Specifications

• Manufacturer: Blodgett
• Model: 981
• Equipment type: Gas baking and roasting deck oven
• Baking compartments: Two
• Compartment size: 42 inches wide by 32 inches deep by 7 inches high per compartment
• Deck thickness: 1 inch
• Deck material: Steel; the 981/951 product listing specifies 12-gauge aluminized steel
• Gas input: 50,000 BTU per section, or 14.6 kW, for natural gas and propane
• Gas types: Natural gas or propane; the 900 Series ovens are not convertible between gas types
• Door feature: Counterbalanced doors
• Exterior material: The listed propane double-deck configuration has a stainless steel front, top, sides and back

Installation & Requirements

Installation and service are for qualified personnel. Connect the oven to a gas supply of the type shown on its rating plate, and follow applicable local requirements. The 900 Series manual cites the National Fuel Gas Code, ANSI Z223.1/NFPA 54, and the Natural Gas and Propane Installation Code, CSA B149.1, as applicable in the United States and Canada. The manual states that 900 Series ovens are not convertible to another gas type. Confirm the oven’s rating plate and gas type before arranging the connection.

The 900 Series manual gives natural-gas inlet pressure limits of 7.0 to 10.5 inches water column and propane inlet pressure limits of 11.0 to 13.0 inches water column. It lists manifold pressure as 5.0 inches water column for natural gas and 10.0 inches water column for propane. Each oven is supplied with a regulator, which the manual describes as essential for proper operation. Gas piping must be sized to supply the demand of connected appliances without loss of pressure at the oven; the manual recommends consulting the gas supplier if pipe capacity is uncertain. Gas pressure should be checked after connection by qualified personnel.

Proper ventilation matters to baking performance. The manual warns that restricted or forced venting can adversely affect the oven’s baking characteristics. It gives examples of forced venting such as adding a fan to a direct-vent pipe or using a canopy hood without the draft diverter. Restricted venting examples include tees, elbows and long horizontal runs. The manual also warns that inadequate venting can create harmful combustion products, operating problems, unsatisfactory baking and possible equipment damage. It says damage directly resulting from improper ventilation is not covered by the manufacturer’s warranty.

Operation

Operation is restricted to qualified personnel. For the lighting procedure in the 900 Series manual, turn the manual control valve to OFF, press the automatic safety pilot valve’s red button, and light the pilot with a match or taper. After the pilot lights, hold the button down for about 30 seconds before releasing it. Turn the manual control valve to ON and set the thermostat to the desired temperature. If the pilot goes out, the manual instructs operators to wait five minutes before attempting to relight.

Allow the oven to reach operating temperature before loading food. The manual’s initial-startup instructions call for preheating to 500°F (260°C) for two hours before loading to allow the paint to set; check the oven periodically during this procedure. The deck is intended for pizza and bread products. Other foods may be cooked in pans or containers. Load each shelf evenly, do not let pans touch one another or the oven sides, and avoid opening the doors unnecessarily. In a two-shelf oven, load the lower compartment first. Turn the manual control valve to OFF to shut down the oven.

Cleaning & Maintenance

Clean the oven when it is cold. For painted and stainless surfaces, the manual recommends wiping with a cloth saturated with light oil and then drying with a clean cloth. For stainless steel, use a non-toxic industrial stainless steel cleaner and rub with the grain of the metal. Baked-on splatter may be treated with an appropriate non-toxic industrial stainless steel cleaner; the manual says heat tint and heavy discoloration may be removed with a non-toxic commercial oven cleaner. Do not spray the oven with a water jet.

• Daily: Brush residue from beneath the doors. The 900 Series manual also recommends removing this residue with a small broom or brush.
• Weekly: Brush out the combustion compartment and control area, and clean the air intakes. The manual notes that air intakes provide cooling air to internal components and are generally at the rear and sides.
• Every six months: Clean the secondary air ducts and air entry ports, as directed by the manual.
• Annually: Check the venting system for deterioration from moisture and corrosive flue products.

For Ultra Rokite decks, the manual specifies a triangular scraper and says not to use water or other liquids on the deck. It also cautions against caustic solutions and domestic oven cleaners on the aluminized interior because they can damage its coating. The manual says no lubrication is required. Contact a Blodgett service company, factory representative or the factory for maintenance or repairs; repairs and adjustments should be handled by qualified personnel.

Troubleshooting

The 900 Series manual lists the following baking symptoms and possible causes. Some remedies involve gas pressure, the flue, thermostat calibration or internal components; the manual marks difficult operations for qualified personnel and recommends using a local Blodgett service agency rather than attempting repairs as an owner or operator.

• Strong bottoms on baked goods: Possible causes include too much bottom heat, high gas pressure, a faulty flue with a strong direct vent, or leaving product in too long. The listed operator remedy is to reduce cooking temperature and increase cooking time, or shorten cooking time where appropriate. Gas-pressure and flue work should be left to qualified personnel.
• Uneven baking: Possible causes include poor ventilation, leaving doors open too long, inconsistent dough scaling, fluctuating gas pressure or warped pans. The manual recommends avoiding unnecessary door opening, scaling dough consistently and changing warped pans.
• Product burning: Possible causes include a thermostat set too high, excessive cooking time, a bypass flame that is too high, high gas pressure, a thermostat out of calibration or worn heat deflectors. The listed basic remedies are to reduce cooking temperature or shorten cooking time; have adjustments and repairs handled by qualified personnel.
• Product drying out: Possible causes include oven temperature that is too low, insufficient water in the product mix, a thermostat out of calibration or a faulty flue with a strong direct vent. The manual lists increasing cooking temperature or water in the mix as operator remedies; calibration and flue issues require qualified attention.
• Extended baking times: Possible causes include a temperature setting that is too low, low gas pressure, strong ventilation or excessive door openings. The manual lists increasing cooking time and avoiding unnecessary door opening; gas pressure and ventilation issues should be checked by qualified personnel.

Applications

The Blodgett 981 is suited to commercial kitchens that bake pizza, bread and other baked goods on deck surfaces, or cook other foods in pans or containers. Its two separate 7-inch-high compartments provide room for distinct loads. Use the oven’s natural-gas or propane configuration that matches the site’s gas supply, and confirm the specific rating plate before installation.