Expert tankless water heater diagnostics and repair. We fix error codes, descale units, replace parts, and restore your endless hot water.
Full diagnostic of error codes to identify the exact issue with your tankless unit.
Thorough descaling to remove mineral buildup and restore optimal heat transfer efficiency.
Inspection and replacement of igniter and flame sensor components for reliable ignition.
Flow sensor testing and calibration to ensure proper water detection and activation.
Fast response times, with same-day repair available across Mississauga, Oakville, Etobicoke and Burlington.
Fully licensed HVAC technicians with comprehensive insurance for your peace of mind.
Upfront quotes with no hidden fees. 0% financing available on qualifying repairs.
Call us today for expert tankless water heater repair in Mississauga.
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Error codes are manufacturer specific, but the common families are ignition failure, flame loss, exhaust or air supply blockage, overheating and flow-sensor faults. Note the code before you reset it, because it points straight at the problem and saves diagnostic time.
Usually the cold-water sandwich, which happens when you draw hot water shortly after stopping. If it happens on every draw rather than intermittently, it is worth checking the flow sensor and the minimum flow rate the unit needs to fire.
Roughly once a year in most of the GTA, and more often on hard water. Scale on the heat exchanger is the single most common cause of premature tankless failure, and most manufacturers require the service to keep the warranty valid.
By design. A tankless heater needs a minimum flow rate before it ignites, so a barely-open tap will not trigger it. If it fails to fire at normal flow, that is a fault worth looking at.
Tankless units generally last longer than tanks and most faults are repairable, so repair is more often the right call. Our pricing list publishes installed prices for Rinnai replacements if it turns out the unit is beyond economical repair.
Repair and maintenance is done on all makes and models. On replacements we most often fit Rinnai, which is what our published pricing covers.
Gas work in Ontario is regulated. Every gas appliance we touch is handled to the standards set by the province’s safety regulator, and any certificate or licence we hold can be verified through them.
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Read all 175 Google reviews“I had an outstanding experience with Real Deal HVAC Services. From start to finish, their team was professional, fast, efficient, and extremely customer friendly. They responded quickly, arrived on time, and got the job done with great…”
“Great job, Shemar!!! Before choosing a company for cleaning the AC evaporator coil, I did a search and found many reviews with positive comments from happy and satisfied customers. It looked almost too good to be true... until you actually came our house to do the servicing... and I experienced the service first hand. Kudos!”
“Excellent trustworthy and honest HVAC repair. Tech was friendly and able to arrive quickly to assess an issue with the AC. Identified the problem and provided different options for repair and payment plan if needed. Excellent will call again when needed.”
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