Free Tools for Gas & Heat Pump Engineers
Calculators and AI checklists built by BoilerTag. No signup, no paywall. Use them on-site, email the results to yourself, and reopen them whenever you need.
AI Boiler Fault Diagnostic Checklist
Tell us the make, model, and fault code. Get a step-by-step diagnostic checklist on the page and emailed to you.
Boiler Size Calculator (kW)
Work out the right kW output for a replacement combi or system boiler in under 30 seconds.
Heat Pump Suitability Checker
A 60-second check to see whether an air source heat pump makes sense for a property.
Radiator BTU Calculator
Size radiators properly for any room. Enter dimensions, insulation, and glazing — get BTU and recommended models.
Gas Rate Calculator
Work out the gas rate (kW) from meter readings. Essential for commissioning and servicing.
MCS Heat Loss Calculator (simplified)
A simplified whole-house heat loss estimate for heat pump and boiler sizing conversations.
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