Volvo C30 2007 Service And Repair Manual page 546

Install the engine coolant heater. See: FUEL FIRED BOOSTER HEATER (B5254T3, B5254T7)
FINISHING
FINAL CHECK OF THE ENGINE COOLANT HEATER
Test run the engine coolant heater and check its function. See: FUEL-POWERED PREHEATER,
CHECKING
Check that no diagnostic trouble codes (DTCs) have been stored while the repair was carried out.
FUEL FIRED BOOSTER HEATER EXHAUST PIPE (B5244S4)
NOTE: The illustrations in this service information are used for different model years
and/or models. Some variation may occur. However, the essential information in
the illustrations is always correct.
REMOVAL
REMOVING THE EXHAUST PIPE FOR THE ENGINE COOLANT HEATER
Fig. 161: Identifying Upper Mounting
Courtesy of VOLVO CARS CORPORATION
2012 Volvo C30 T-5
HVAC Climate Units - Removal, Replacement And Installation