Water Heating · Toronto & GTA
Condensing Tankless Water Heaters
Stop renting a 50-gallon storage tank you don't use half the day. A condensing tankless heats water on demand at 96% thermal efficiency, delivers 8+ gpm of endless hot water, and lasts 20+ years — twice the life of a rental tank.
$3,500 – $6,500 installed (Rheem / Rinnai, GTA)
What is a tankless water heater?
A tankless (or 'on-demand') water heater is a wall-hung gas or electric appliance that heats water only when a hot-water tap is opened — unlike a traditional storage tank, which keeps 40–75 gallons of water hot 24/7 whether you're using it or not. The moment you open a hot tap, the tankless senses the flow, ignites the burner, and delivers heated water within about 10–15 seconds. Close the tap and the burner shuts off.
In Toronto and the GTA, the two most common configurations we install are Rheem condensing gas tankless units (RTGH series) and Rinnai condensing tankless (RUR199iN). Both are indoor wall-hung, both use direct-vent PVC or polypropylene, both deliver 8–11 gpm at typical inlet temperatures, and both run at 94–96% thermal efficiency — meaning 94–96¢ of every dollar of natural gas becomes hot water at the tap.
The reason we push ownership over rental so hard: a $40–$50/month rental tank costs $10,000–$15,000 over its 15-year lifespan; a purchased tankless costs $3,500–$6,500 installed, lasts 20+ years, cuts water-heating energy use 20–40%, and stays owned equity when you sell the house. See our 'Own It, Don't Rent Forever' campaign for the full math.
| Thermal efficiency | 94 – 96% (condensing) | vs. 60–70% for a rental tank |
|---|---|---|
| Flow rate | 8 – 11 gpm | Supports 3–4 fixtures simultaneously |
| Wall footprint | ~28 × 18 × 12 inches | vs. 60-gallon tank at ~60 × 22" diameter |
| Lifespan | 20+ years | Rental tanks: 10–15 years |
| Warranty | 12–15 years heat exchanger | 5–6 years parts, 1 year labour |
| Ownership savings | $6,000–$10,000 over 15 yrs | vs. renting the equivalent unit |
When a tankless upgrade is worth it
Tankless is not automatically the right answer for every home. Here are the four scenarios where the ownership + install math clearly wins.
You've been renting your water heater for years
Reliance, Enercare, and other GTA rental programs charge $30–$50/month indefinitely — often for equipment that was fully paid for 5+ years ago. Cancelling the rental and owning a tankless typically pays back the purchase in 5–7 years and saves $10,000+ over 15 years.
You run out of hot water
Big family, back-to-back showers, dishwasher + laundry + bath all running? A 40- or 50-gallon storage tank runs cold in 15–20 minutes. A condensing tankless delivers endless hot water for as long as you need it — as long as flow stays within the unit's gpm limit (typically 8–11 gpm).
You're renovating a small mechanical room or basement
A wall-hung tankless frees up roughly 4–6 sq ft of floor space compared to a storage tank. In finished basements, that's often the difference between a usable rec room and a cramped one. It also opens up rerouting condensate lines, gas lines, or adding a laundry sink.
You're planning a whole-home electrification retrofit
If you're adding a heat pump, solar, or EV charging, a condensing gas tankless is 20–30% more efficient than a rental tank on the same load — often the smallest incremental cost to reduce your home's gas footprint. Alternatively, we install electric heat-pump water heaters for full electrification.
What we see go wrong on tankless installs
First-party observations from 14+ years of tankless installs across Toronto. Get any of these wrong and you're chasing warranty claims for a decade.
Under-sized gas line
A tankless can draw 180,000–199,000 BTU/hr — usually 2–3× the demand of the tank it's replacing. Toronto homes built pre-2000 often have 1/2" gas trunk that's too small. Un-corrected, you get flame-out under load, error codes on the display, and a warranty claim that gets denied because the gas pressure is out of spec. We check gas line sizing on every install and upgrade to 3/4" or 1" where required.
Wrong venting material or diameter
Condensing tankless exhaust contains acidic water vapour. Wrong-material PVC (schedule 40 vs. cellular core), back-slope, or too-long horizontal runs cause condensate freeze-ups in winter and premature heat-exchanger failure. Our installers spec every vent with the manufacturer's chart in hand and confirm draft with a manometer at commissioning.
Skipping annual descaling on hard water
Southern GTA municipal water hardness runs 130–200 mg/L — hard by any standard. Without annual descaling (flushing the heat exchanger with a vinegar or citric-acid solution), scale accumulates on the exchanger walls, drops efficiency, and eventually cracks the fins. Every tankless we install includes isolation valves and a first-year descaling included so year 1 is easy.
Undersizing the tankless itself
'Endless' hot water is endless only until you exceed the unit's gpm rating. A single unit sized for 8 gpm can support ~2 showers + a bathroom sink simultaneously. A large family with multiple bathrooms may need an 11-gpm unit or two tankless units cascaded. We do a peak-demand calculation before we quote — never just a 'like-for-like' swap.
Why homeowners choose Energy Clean for tankless water heaters
We've installed tankless across the GTA since 2012. “Own It, Don't Rent Forever” is a founding value, not a campaign.
- TSSA Registration #000214220
- Trane Comfort Specialist
- Home Depot Approved Contractor
- Baeumler Approved
- Google 4.9 · 308 verified reviews
Equipment we fit: Rheem (RTGH series) · Rinnai (RUR199iN) · Navien
Serving Woodbridge, Vaughan & the GTA since 2012
How our tankless install works
- 1
Free in-home assessment
A senior advisor measures existing gas line diameter, checks venting paths, confirms flow-rate demand, and reviews your existing rental contract terms (if any). Written spec, no obligation.
- 2
Rental cancellation
If you're currently renting, we handle the rental cancellation paperwork with Reliance / Enercare / EnerCare Home Services on your behalf — including scheduling the removal and confirming there's no early-termination penalty.
- 3
Rebate + permit filing
We pull the gas + venting permits, register the manufacturer's warranty, and file every eligible Enbridge, IESO, and Ontario Home Renovation Savings rebate.
- 4
Single-day install
Old tank + rental gear out, tankless mounted, gas line + vent + condensate all built to spec. Typical install is 6–10 hours depending on gas line upgrades. You keep hot water the whole day except for the ~2-hour cutover window.
- 5
Commissioning + water quality test
We measure water hardness on-site, commission the burner to the manufacturer's spec, dial in the temperature setpoint, and if your hardness is above 150 mg/L we recommend a water softener sized to protect the heat exchanger.
- 6
Year 1 descaling included
First-year descaling service is included on every install — so you experience the annual maintenance visit yourself and know what to expect long-term.
Related products
Tankless questions, answered
A tankless water heater has no storage tank. When a hot-water tap opens, a flow sensor inside the unit detects the demand, ignites the gas burner (or engages the electric element), and heats water as it passes through a heat exchanger. Water arrives at the tap at your set temperature within 10–15 seconds. Close the tap and the burner shuts off — so you're only paying to heat water you actually use.
Endless hot water (no more running out mid-shower), 20–40% lower energy costs (no standby heat loss keeping a tank hot 24/7), 20+ year lifespan (roughly double a storage tank), and a much smaller physical footprint (wall-hung, freeing 4–6 sq ft of floor space). Owned tankless equipment also carries equity when you sell — versus a rental contract that just transfers.
Yes — a Rheem RTGH-95 or Rinnai RUR199iN (both roughly 8–11 gpm) supports a family of 4–5 running back-to-back showers plus a dishwasher without running cold. For very large families or homes with 4+ bathrooms, we sometimes install two tankless units cascaded so peak demand at 15–20 gpm is fully covered. We size against actual peak demand, not a guess.
Yes. Annual descaling is required to preserve the manufacturer warranty and to keep efficiency at 96%. Southern GTA municipal water hardness (130–200 mg/L) accelerates scale buildup on the heat exchanger. We install isolation valves on every job so the annual descaling flush is a 30–45 minute service call, and we include the first-year descaling free with every install.
Gas condensing tankless (Rheem RTGH, Rinnai) is roughly 3–4× more efficient at delivering hot water at high flow rates than an electric tankless, and cheaper to run on Ontario gas rates. Electric tankless is a fit for tiny loads (single bathroom, cottage bunkie) or for full electrification retrofits where natural gas isn't available. For most GTA family homes, condensing gas is the right call.
A properly-installed Rheem or Rinnai condensing tankless with annual descaling typically lasts 20–25 years — roughly double a rental storage tank. That lifespan is a big part of why the ownership economics work: you're comparing 20 years of $0/month against 20 years of $40/month rental. Even after paying for the install, ownership wins by $6,000–$10,000+ over that horizon.
Get In Touch
Stop renting. Start owning endless hot water.
Book a free in-home tankless assessment — a senior advisor confirms sizing, gas line, and venting feasibility and hands you a written quote in 24 hours.
905-417-4440 · Licensed & Insured · Free Estimates · Financing Available