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Cast-Iron Radiator EDR Sizing Verification Checklist

Essential Checklist+

Complete these critical checks before approving the work or proceeding to the next construction stage.

✓11 Inspection Points
✓4 Verification Categories
✓EDR Determination+
  • If the radiator's actual EDR is documented anywhere (nameplate, manufacturer catalog, old boiler replacement paperwork), that value was used directly instead of the tube-count table
  • Tube or column count correctly identified by looking at the radiator from its narrow end, not guessed from its overall appearance
  • Number of sections counted directly on the physical radiator (each cast-iron 'slice'), not estimated from its overall width
  • Confirmed the radiator being sized is a floor-standing column or tube type, not a flat wall-hung (wall type) radiator
✓System Type & Temperature+
  • System type (steam vs. hot water) matches the actual heating system, not assumed from the radiator's appearance alone
  • For a hot-water system, the entered average water temperature reflects the system's actual current operating temperature (boiler aquastat/reset curve setting), not an assumed historical default
  • Confirmed the entered water temperature is the AVERAGE of supply and return, not the boiler's supply temperature alone
✓Target & Sizing Decisions+
  • If a target heat output was entered, it came from an actual room heat-loss/load calculation, not a guess
  • Understood that the required-sections figure is rounded UP to the next whole section, and that ordering exactly that many (not fewer) is what actually meets the target
  • Confirmed this calculator's output sizes the RADIATOR, not the boiler serving it — a separate boiler-sizing calculation (with its own piping/pickup allowance) still applies
✓Physical Verification+
  • For any radiator replacement, relocation, or new boiler sizing decision, a licensed heating contractor was consulted rather than relying on this calculator alone
Full QC Checklist+

Verify EDR determination, system type and temperature, target and sizing decisions, and physical verification for a cast-iron radiator EDR sizing estimate.

✓20 Inspection Points
✓4 Verification Categories
✓EDR Determination+
  • If the radiator's actual EDR is documented anywhere (nameplate, manufacturer catalog, old boiler replacement paperwork), that value was used directly instead of the tube-count table
  • Tube or column count correctly identified by looking at the radiator from its narrow end, not guessed from its overall appearance
  • Number of sections counted directly on the physical radiator (each cast-iron 'slice'), not estimated from its overall width
  • Understood that height scaling from the 26 in reference is an approximation, not a verified per-height table, for a radiator meaningfully taller or shorter than ~26 in
  • Confirmed the radiator being sized is a floor-standing column or tube type, not a flat wall-hung (wall type) radiator
  • Radiator height measured as the overall height, floor to top — including the legs/base, not just the cast-iron body above them
✓System Type & Temperature+
  • System type (steam vs. hot water) matches the actual heating system, not assumed from the radiator's appearance alone
  • For a hot-water system, the entered average water temperature reflects the system's actual current operating temperature (boiler aquastat/reset curve setting), not an assumed historical default
  • Confirmed the entered water temperature is the AVERAGE of supply and return, not the boiler's supply temperature alone
  • If retrofitting a condensing or modulating boiler onto existing cast-iron radiators, accounted for the real possibility of a large (up to ~two-thirds) output reduction at a low average water temperature
  • Confirmed this radiator's actual piping doesn't mix steam and hot-water distribution — the two systems use different pipe sizing, venting, and pitch requirements entirely
✓Target & Sizing Decisions+
  • If a target heat output was entered, it came from an actual room heat-loss/load calculation, not a guess
  • Understood that the required-sections figure is rounded UP to the next whole section, and that ordering exactly that many (not fewer) is what actually meets the target
  • Confirmed this calculator's output sizes the RADIATOR, not the boiler serving it — a separate boiler-sizing calculation (with its own piping/pickup allowance) still applies
  • If a room has more than one radiator, each was sized separately and their outputs summed, rather than treating the room as having a single combined radiator
  • If comparing this calculator's output against an old boiler's nameplate rating, confirmed which basis that nameplate figure actually uses (NET vs. GROSS I=B=R), not assumed
✓Physical Verification+
  • Radiator confirmed unobstructed by furniture, drapes, or covers that would reduce its real delivered output below this calculation
  • For a hot-water radiator, air bleed valve checked and system properly purged of air, and for a steam radiator, the air vent checked for proper operation
  • For any radiator replacement, relocation, or new boiler sizing decision, a licensed heating contractor was consulted rather than relying on this calculator alone
  • For a steam system, each radiator's own air vent checked for a venting rate appropriate to that radiator's actual EDR, not left as a generic one-size-fits-all vent
Inspection Notes+
Use the latest approved drawings, specifications, and site measurements.
Complete all critical checks before proceeding to the next work stage.
Record deviations and confirm rectification where required.

Related Calculators & Guides

Cast-Iron Radiator EDR Sizing CalculatorOpen the related calculator and verify the current project inputs.

FAQ

Use it after collecting the project inputs and again before approving or closing the relevant work stage.
No. It supports verification but does not replace approved drawings, specifications, codes, manufacturer requirements, or professional inspection.