What is the distance between heat detector and a smoke detector?

The maximum distance between any point of an area to the detector, should be, 5.3m for Heat detectors, 7.5m for Smoke detectors.

Minimum distance between detector (other than beam detectors) and wall or partition should bemm.

The coverage of smoke detector is a circle with diameter = meters and for heat detector  d=.6 meter.The distance between the smoke detector and another smoke detector =.5 meters (from center of smoke to center of the other smoke detector) and between two heat =7.5 meters under a flat horizontal ceiling.so between smoke and heat detector will depend on your requirements but not more than.5 meter

According to NFPA 72 edition 2013 Section 17.6.3.1.1 # Detector spacing.

All points on the ceiling shall have a detector within a distance equal to or less than 0.7 S (S is the listed Spacing). Equal to S = 9.1 Mtr. For Smoke detector , S= 15.2 Mtr. For Heat detector and the spacing between the detector must not be less than 0.4 S.

·         For Heat detector.

Heat detector spacing distance effective by the Ceiling height so we have another factor depend on the ceiling heat you can find this Factors on NFPA 72 edition 2013 Table 17.6.3.5.1 # Table heat detector spacing reduction based on ceiling height.  

·         For Smoke detector.

Smoke detector spacing distance effective by the air movement speed, so we have another factor depend on the Air movement you can find this Factors on NFPA 72 edition 2013 Table 17.7.6.3.3.2 # Table Smoke Detector Spacing Based on Air Movement.

and the spacing between detector and wall equal to .5 S , and corner .75 S.

All above for Smooth Ceiling