Flat water radiator in central section of upper wing.
Purging the air from a hot water radiator is not difficult.
Several companies offer slender, wall-mounted variations of the steam or hot water radiator.
Hot water radiators should be bled at least once each year, usually at the start of the season.
To bleed a hot water radiator, first turn the heat on and let the system come up to capacity.
Lighting was electric and heat was provided with hot water radiators.
Hot water radiators should be "bled" to insure that there is no air in the system.
More simply they may be oil-water coolers, where an oil pipe is inserted inside the water radiator.
Last 30 were improved variant H-19a, with a water radiator placed under engine, instead of above engine.
In addition, a water radiator was placed upon the engine, what obstructed view from a cab.