Approach temperature
Heat Interface Units (BG 62/2015) was written by Reginald Brown and published by BSRIA in December 2015. It states: ‘The approach temperature is the smallest temperature difference between the primary and secondary fluids at any point within a heat exchanger. It depends on the design of the heat exchanger and the operating conditions. For a counter flow or cross flow plate heat exchanger it will usually be the difference between the primary return temperature and the secondary return temperature. Ideally for network efficiency, the approach temperature should be as small as possible, but reducing the approach temperature for a given heat transfer rate means increasing the physical size and therefore cost of the heat exchanger.’
--BSRIA
[edit] Related articles on Designing Buildings
- A technical guide to district heating (FB 72).
- Big growth in district heating markets - now and on the horizon.
- BSRIA articles.
- BSRIA definitions.
- BSRIA guide to heat interface units.
- Communal heating.
- Direct heat interface unit.
- District energy networks
- Domestic micro-generation.
- Heat exchanger.
- Heat interface unit.
- Indirect heat interface unit.
Featured articles and news
A change to adoptive architecture
Effects of global weather warming on architectural detailing, material choice and human interaction.
How big is the problem and what can we do to mitigate the effects?
Overheating guidance and tools for building designers
A number of cool guides to help with the heat.
The UK's Modern Industrial Strategy: A 10 year plan
Previous consultation criticism, current key elements and general support with some persisting reservations.
Building Safety Regulator reforms
New roles, new staff and a new fast track service pave the way for a single construction regulator.
Architectural Technologist CPDs and Communications
CIAT CPD… and how you can do it!
Cooling centres and cool spaces
Managing extreme heat in cities by directing the public to places for heat stress relief and water sources.
Winter gardens: A brief history and warm variations
Extending the season with glass in different forms and terms.
Restoring Great Yarmouth's Winter Gardens
Transforming one of the least sustainable constructions imaginable.
Construction Skills Mission Board launch sector drive
Newly formed government and industry collaboration set strategy for recruiting an additional 100,000 construction workers a year.
New Architects Code comes into effect in September 2025
ARB Architects Code of Conduct and Practice available with ongoing consultation regarding guidance.
Welsh Skills Body (Medr) launches ambitious plan
The new skills body brings together funding and regulation of tertiary education and research for the devolved nation.
Paul Gandy FCIOB announced as next CIOB President
Former Tilbury Douglas CEO takes helm.
UK Infrastructure: A 10 Year Strategy. In brief with reactions
With the National Infrastructure and Service Transformation Authority (NISTA).
Ebenezer Howard: inventor of the garden city. Book review.
Airtightness Topic Guide BSRIA TG 27/2025
Explaining the basics of airtightness, what it is, why it's important, when it's required and how it's carried out.