Question

We have had architects on the small kitchens we’re designing (both of which have condense/self-vent hoods rather than ventilation) asking what heat the equipment that’s being put in, will generate. As we have not been asked this before we wondered if the members could advise?

Replies

1. I would think that the suppliers/manufacturers like Hobart, Winterhalter, Meiko, etc., could/would provide this information.
2. This issue is one of general ventilation as the self-condensing hoods recirculate the air removing smells and vapour that is then put to the main drain of the oven. Some of the heat will then go down the drain but not all of it. In this case we would normally specify the Ultravent Plus from Rational.Rational Spec: Our UltraVent® condensation technology is also available in an UltraVent® Plus model, which is equipped with special filters to prevent steam as well as bothersome smoke that could otherwise develop when grilling or roasting. This makes it possible to install RATIONAL units in more demanding locations as well, such as front cooking areas.As a failsafe we always ask for some general extraction and make up air to deal with the heat issue.
3. When I am asked for this I advise the heat rejection for all refrigerated appliances (which can normally be easily gained from the manufacturers cut sheet’s) and the electrical or gas connected load for all cooking appliances, its then for the M and E consultant to calculate the heat rejection allowance.They should do/normally do this based on the CIBSE guide http://www.cibse.org/knowledge/knowledge-items/detail?id=a0q20000008I79JAAS section 6.7 which takes the heat gain calculation from ASHREA Table 6.17 Typical rates of heat gain from restaurant and cooking equipment (6)(Copyright 2005, ©American Society of Heating, Refrigerating and AirConditioning Engineers, Inc. (www.ashrae.org) see section 6 of the below Guide:CIBSE-Guide-A-Environmental-Design.pdf 

   This may have been updated since this publication.

4. This information should be taken from the KW load which their M&E consultant should be able to calculate. Fridge manufacturer should be able to. Advise on the heat dump. Please note even if self venting with no dedicated cooking extract the rooms will need fresh air changes to comply with regs.