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Boiler Repair & Installation · Hamilton, OntarioBoiler Repair & Installation in Hamilton
Boiler repair and installation in Hamilton starts with a rule: repair a cast-iron boiler for as long as the iron holds water, and replace it when the sections or the heat exchanger leak. Most calls are a circulator, a zone valve, an expansion tank or a relief valve, fixed for $150–$800 after a $90–$150 diagnostic. A replacement is quoted in writing after we count the radiators and see the piping and the chimney.
Boiler service for Hamilton's radiator houses: repair first, replace when the iron leaks
Hamilton's boilers are concentrated below the Escarpment and in Dundas. The pre-war brick houses of Westdale, Durand, Kirkendall and Strathcona were built with cast-iron radiators, and many were piped as gravity systems: no pump, large-diameter steel mains, hot water rising by convection alone. Most have since had a circulator added, but the wide pipes and the large water volume are still there. That history explains most of what we find on a service call.
The expansion tank is the usual culprit. Older systems have a plain steel tank strapped between the basement joists, and once it fills with water there is no air cushion left, so pressure climbs toward 30 psi every time the boiler fires and the relief valve dumps onto the floor. Draining that tank, or replacing it with a bladder-type tank charged to the system's cold fill of 12–15 psi, ends the puddle. After that come seized circulators, zone valves stuck closed, aquastats that no longer hold temperature and pilots that will not stay lit.
A new condensing boiler in one of these houses is a piping job as much as an appliance swap. Decades of iron oxide sludge sit in the old mains and will foul a modern heat exchanger, so the system is flushed and a dirt separator with a magnet goes on the return. The big water volume also means the boiler gets its own piping loop, so it sees the flow rate its manufacturer requires. The new unit vents through the side wall in plastic pipe, and if a gas water heater is left alone on the masonry chimney, that flue needs a liner sized for it.
One caution before any of that work: white or grey wrap on the old pipes may contain asbestos. We do not cut or disturb it, and removal is a job for an abatement contractor before the boiler work is scheduled. For the bigger picture, read heating a Hamilton century home, see the boiler repair and installation page for symptoms and parts, or the Hamilton heating page for furnace and heat pump options. To have a boiler looked at, book a visit.
Why ZK Mechanical for boiler repair & installation in Hamilton
- TSSA-licensed gas technicians who work on cast-iron, condensing and combi boilers
- Expansion tank, relief valve and fill pressure checked on every call, because that trio causes most leaks
- Radiators kept: the boiler is replaced and the cast iron stays
- Old gravity-piped systems flushed and fitted with a magnetic dirt separator before a condensing boiler goes in
- Chimney liner priced into the quote when the water heater is left alone on the flue
- Radiators measured before we say whether a combi or a low-temperature boiler will keep up
- Boiler no-heat calls taken on the 24/7 line with no after-hours surcharge
Licensed technicians, Hamilton dispatch, no overtime charges.
Boiler Repair & Installation in Hamilton — FAQs
How much does boiler repair cost in Hamilton?
The diagnostic visit is $90–$150. Typical repairs, such as a circulator pump, a zone valve, an expansion tank or a relief valve, run $150–$800 with parts and labour. A new boiler has no single price: radiator count, the venting route, the condition of the old piping and whether you want domestic hot water from the same unit all change it. That quote is written after a site visit and costs nothing.
Is it safe to keep running a boiler that is dripping or losing pressure?
A slow drip from the relief valve with the gauge well under 30 psi can usually wait a few days with a bucket under the pipe. Never cap or plug that valve; it is the safety device. Shut the boiler off and call if the gauge reads near 30 psi, if water is coming from the boiler body itself, or if you see soot around the draft hood. If you smell gas, leave the house and call Enbridge Gas first.
Should I repair or replace a 35-year-old boiler in a Westdale or Durand house?
Repair it if the fault is a pump, valve, tank or control and the cast-iron sections are dry. Those parts are external, and the boiler body may have years left. Replace it when the sections leak, when the burner or controls are no longer available, or when one repair costs more than half the price of a new boiler. Repair or replace a boiler works through the decision.
Can a combi boiler heat an old Hamilton house and its hot water?
Often, but not always. A combi makes domestic hot water on demand and heats the radiators from one wall-hung unit, which frees the floor where the tank stood. The limits are hot-water flow with two showers running and the heat a large brick house needs in January. We measure the radiators and count the bathrooms first, and say so when a boiler with a separate indirect tank is the better fit.
Do I need a permit to replace a boiler in Hamilton?
The gas work is done by a TSSA-licensed technician to CSA B149.1 in every case. Whether a building permit is also required depends on the scope of the job, and that decision belongs to the City of Hamilton Building Division, so we confirm it with them before the work is booked. Enbridge Gas is only involved if the new boiler's input means the meter has to change.
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Boiler Repair & Installation in Hamilton — fast.
Emergency repair or planned upgrade, quoted in writing before any work starts.