Before buying, consider the volume and type of food product to be cooked and how it will suit your menu.
When specifying combi ovens for large facilities, consultants can request that the suppliers development chef spends two or three days training staff, who may also be offered training at the supplier's test facility where they can train using their own food products. Most of the main manufacturers offer this service so it's in your interest to ask about the level of support.
If you are consistently doing one type of operation with one oven, youhave to question why? Understand the demands of your operation. Design consultants have walked into a kitchen with 2 x 10-grid combis - one signed 'Bake Only', the other 'Steam Only'. Would a steaming oven and convection oven set-up have been more suitable?

If you are regularly regenerating for banqueting, why not choose a dedicated regeneration oven?
If the menu involves a substantial volume or repeat or standard products, then a programmable combi is preferable. A la carte operations may not need programs but the operator/ chef needs to be more 'clued up' to get the best from the oven.
Combi control panels which use symbols can help remove the fear factor from using a combi. Staff just have to press the right button, whilst the manager sets the programme. Suppliers can offer two types of training programme, one for the manager, the other for the operators.
Do you have space for a freestanding 20-grid combi or would 2 x 10-grid units be more flexible?
You have to get the new combi into the building and in 5-10 years time it will need replacing. Consider where it is going and how it is going to get in!
Drain heat recovery can be used to pre-heat incoming water.
Reversible fans provide better air movement and a longer life for the motors.
Ease of cleaning, access for cleaning to fans and filters and self cleaning oven options all come at a price; a hard to clean unit or one with awkward access to filters will not last as long or perform as well as better designed ovens.
Service it! Combi ovens are very complicated machines and they will only perform efficiently if regularly serviced.

Tips from The Catering Equipment Distributors Association (www.ceda.co.uk)

Given that your single combi oven can't cope with the full volume demanded during service, what do you do? Multiple units from the same maker might be an answer. Or how about a combination of a top-name manufacturer for the main oven and a less well known name in the back-up role, which will solve your problem and produce cost savings. Do you need a second combi - how about a convection oven instead?
Find out about energy consumption and water usage. Some combi manufacturers are better than others at providing data and the difference in energy consumption alone could save you thousands in pounds over the life of the machine.
What level of controllability do you need? Will your staff rely on the pre-programmed options to cook? Or are they fully skilled in using all the elements of combination ovens and don't need (or want) the programmes - in which case you could save money by buying a less sophisticated model.

Advice from The Catering for a Sustainable Future Group (www.csfg.co.uk)

When deciding on whether a combination oven is energy efficient for a particular kitchen operation, always make sure that the correct energy usage information is obtained from the manufacturer. The highest energy usage can be twice that of when the oven is in 'combi' mode; sometimes the energy usage can be twice that of when the oven in in convection mode. It is also important to obtain the maximum water usage figure from the manufacturer, which is usually when the oven is in 'combi' mode.

Energy Efficient Combi-Ovens

Direct-heated gas combi-ovens can be more energy efficient than thos using a heat exchanger to apply indirect heat.
A triple glazed viewing door can save up to 40% of energy compared to a single glazed door.
Automatic fan switch-off, with a brake initiated when the door is opened will retain hot air within the oven and minimise heat loss. It will also help to reduce heat gain in the kitchen.
Combi-ovens are available that minimise the escape of heat through the exhaust.


Advice & comments from CSC Public Sector Equipment Guide February 2010