Estimate only — your licensed installer confirms final sizing

Residential Equipment Sizing & Engineering Tools

Quick estimates using Ontario climate conditions (−20°C winter design temperatures and 40°F groundwater inlet). Select an equipment category below to calculate required capacities before requesting trade quotes.

Estimate only — your licensed installer confirms final sizing
Ontario Climate Tested (−20°C & 40°F)
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Top Manufacturer Models

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Tell us about your home or pool and we will send a written quote with matched equipment. A licensed contractor should confirm final sizing.

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MOST POPULAR · ONTARIO
Bosch IDS 2.0 · Modulating Inverter

Furnace, AC & Heat Pump Sizing Guide

Calculate recommended furnace output (BTU/hr) and heat pump / AC capacity (Tons) based on above-grade square footage, home architectural style, and construction insulation era.

  • • Target Applications: Detached, Semi-Detached & Bungalows (600–5,000 sq ft)
  • • Method: Rough heat-loss estimate & Ontario basement exclusion rule
  • • Reference Tables: 3 Complete Ontario Sizing Reference Tables included
Launch Sizing Guide & Charts →
COLD-CLIMATE (−20°C TO −30°C)
Mitsubishi Zuba · Moovair Central-Moov

Cold-Climate Heat Pump Load Calculator

Calculate heat pump tonnage to maintain 100% heating capacity during sub-zero Ontario winters. Size modulating inverter turndown and dual-fuel auxiliary balance points.

  • • Climate Design: GTA (−20°C), Central (−25°C), and Northern ON (−30°C)
  • • System Types: 2.0 to 5.0 Ton Inverter Ducted Central & Multi-Zone
  • • Output: Exact Tonnage + Dual-Fuel / Electric Strip Balance Point
Calculate Heat Pump Tonnage →
TANK (40-60 GAL) · TANKLESS · HYBRID
Bradford White · Navien NPE-A2 · Rinnai REHP

Water Heater Sizing: Storage Tank, Tankless & Hybrid

Size Bradford White gas power-vent storage tanks (40, 50, 60 Gallons) by First Hour Rating (FHR), or calculate winter flow rates (GPM) for Navien condensing tankless systems and Rinnai hybrid heat pumps.

  • • Storage Tanks: 40, 50, or 60 Gal based on household occupants & 82+ Gal FHR
  • • Tankless Thermodynamics: Full 80°F ΔT winter rise (40°F inlet to 120°F outlet)
  • • Output: Exact Tank Gallons & FHR, Tankless 199k BTU Flow, or Hybrid Capacity
Launch Water Heater Sizing Guide →
SALTWATER IMMUNE NITEK
Rheem AVIA HD NiTek · Pentair MasterTemp · Moov

Gas vs. Inverter Pool Heater Sizing

Model surface heat loss and recovery hours for Ontario swimming pools from May opening through October closing. Compare high-BTU gas heaters with high-efficiency inverter heat pumps.

  • • Loss Equations: Surface evaporation + wind velocity + overnight temperature drop
  • • Metallurgy Guide: NiTek Nickel Alloy & Titanium for 100% saltwater durability
  • • Output: Recommended BTU/hr (264k–400k) & Inverter Heat Pump kW
Calculate Pool Heater BTU →
HORSEPOWER (HP) · 3-STAGE RPM ENGINE
Pentair IntelliFlo3 VSF 3.0 HP · Hayward TriStar VS

Variable-Speed Pool Pump: Horsepower & RPM Guide

Calculate required motor horsepower (HP) and exact 3-stage operating RPM schedules (low-speed filtration, medium skimming/heating, high-speed vacuum/backwash) based on pool volume and APSP-15 turnover standards.

  • • Motor Horsepower: Sized for 1.85 HP, 2.7 HP, or 3.0 HP High-Head VSF
  • • RPM Schedule: Exact programmable speeds (1,450 RPM low vs 2,350 RPM mid vs 3,200 RPM peak)
  • • Hydro Savings: Up to 80% electrical reduction (~$675 to $1,200/season in Ontario)
Calculate Pump HP & RPM →
OESC 200A SERVICE & EV CAPACITY
Grizzl-E · Autel · Leviton

Smart Electrical Panel & EV Service Load

Audit existing 100A vs 200A electrical service capacity under the Ontario Electrical Safety Code (OESC) when adding Level 2 EV chargers, central heat pumps, and induction ranges.

  • • EV Circuits: Dedicated 40A / 50A / 60A breaker branch circuit continuous sizing
Calculate Electrical Service Load →
ESSENTIAL VS WHOLE-HOME BACKUP
Generac Guardian 22kW · Automatic Transfer Switch

Standby Generator kW & Gas Supply Sizing

Calculate starting locked-rotor amperage (LRA) vs continuous running wattage for critical home circuits: heat pumps, sump pumps, well pumps, refrigeration, and medical devices.

  • • Surge Capacity: High-inductive compressor motor starting kW vs continuous kW
  • • Fuel Supply: Natural gas meter flow (300k+ BTU/hr inlet) & LP tank delivery
  • • Output: Recommended Generator kW (18kW–24kW) + 200A ATS configuration
Calculate Generator kW & Gas Supply →
ONTARIO WINTER DRYNESS · IAQ
AprilAire 700 · 800 Steam · 600 Series

Whole-Home Humidification & IAQ Sizing

Size daily moisture output (Gallons Per Day) to protect engineered hardwood floors and maintain 35–45% relative humidity through dry Ontario winter heating cycles.

  • • Envelope Infiltration: Tight (new construction) vs average vs loose air changes/hour
  • • Technology Comparison: Evaporative bypass (17 GPD) vs fan-powered (18 GPD) vs steam (up to 34.6 GPD)
  • • Output: Exact GPD moisture demand & humidifier model matching
Calculate Humidifier GPD & IAQ →
Engineering Best Practices

Why Accurate Sizing Matters in Ontario

Unlike southern climates, Ontario homes experience extreme 65°C annual temperature swings (−25°C in January to +40°C humidex in July). Rule-of-thumb contractor estimates frequently lead to oversized equipment and degraded home comfort.

The Peril of Equipment Oversizing

Bigger is not better in HVAC. An oversized furnace or heat pump satisfies the thermostat in 6 minutes, causing frequent short-cycling, severe duct noise, and high electric peaks. In summer, oversized AC shuts off before removing indoor humidity, leaving indoor air cold and clammy.

The Ontario Basement Sizing Rule

Never include basement square footage directly when sizing furnaces or heat pumps with general tables. Because basement walls are surrounded by earth at a constant 8–10°C, their heat loss is only 20–25% of above-grade floors. Adding 1,000 sq ft of basement will oversize your heating system by 1 to 1.5 tons.

Winter Groundwater ΔT Rise (40°F)

In Toronto and Southern Ontario, municipal water main temperatures drop to 4–5°C (40°F) in January. Sizing a tankless water heater for a 120°F target requires an 80°F temperature rise. Units rated for 9 GPM in Florida will deliver only 4.5–5.0 GPM in Canadian winter conditions.

200A Electrical Capacity vs Smart Shedding

Adding a 48A EV charger and a 4-ton cold-climate heat pump to a standard 100A or 200A service often triggers an expensive utility transformer upgrade. Your licensed electrical contractor can advise whether load management or a service upgrade is needed.