Heating System Repair for Residential Landlords

Having residential heating system repair skills can really prevent a landlord from getting "hot under the collar" when a tenant complains that there's no heat.

With a little knowledge of how the basic types of central heating systems work, a landlord can successfully diagnose and repair most problems that develop. And getting the heat back on will surely make the tenants happy!

Let's take a look at the most common issues that develop which require heating system repair, maintenance, or replacement.

• Thermocouple Replacement - A natural gas boiler and hot water tank each have a safety device called a thermocouple. This device is needed to sense the "pilot flame". The pilot flame must remain lit in order to light the main burners when heat is called for by the thermostat.

  If the pilot flame goes out, or the thermocouple becomes defective, the gas valve will close and the burners will not light, hence heat will not be produced. A defective thermocouple is a common heating system repair problem.

  It can be removed by unscrewing it from one end at the gas valve and removing it from its mounting bracket (near the gas pilot line) at the other end. A new replacement thermocouple should be the same length and rating (usually 30 millivolt) as the original one.

  Performing this heating system repair yourself can save you a hefty service charge from a heating technician.




• Water Heater Replacement
  - Replacing a defective water heater is probably the biggest heating system repair job that a residential landlord will face. The old heater will first have to be fully drained and then disconnected from its hot and cold water lines and, if it's a gas water heater, its gas supply shutoff valve must be closed before disconnecting the gas line from the unit.

  If the heater is an electric water heater, the electric power that feeds the unit must be terminated by opening the circuit breaker or fuse in the main electric distribution panel. Then, the power supply line should be tested (at the heater unit) to verify the power is off before removing the power line from the heater's junction box.

  The defective water heater should then be discarded and replaced with a new one of the same size and capacity. The job will be completed by connecting the new unit to the water supply lines, gas (or electric) lines, and filling it with water (while the hot water faucets are open to release air).


• Oil Filter Replacement for Oil Burners - If the oil filter gets clogged up, the burner unit won't fire (or will fire intermittently, a condition known as "puffing").

  To replace the filter, shut off power to the burner unit at the emergency switch located at the boiler. Then, unscrew the bolt that holds the cylindrical canister section (that houses the filter) to its top section. Lower the canister slowly because it will be filled with oil and discard the dirty oil and filter into a container for proper disposal.

  Replace the old filter with a new one of the same type (make and model number) which will fit into the canister. Reassemble the canister and turn the emergency switch back on. The air inside the oil line will then have to be bled by opening the "bleeder screw" at the burner unit.

• Air Filter Replacement - This is required for central heating systems that have furnace units which heat air and force it through ducts to supply heat throughout the house. A clogged air filter will reduce the amount of air flow and heat supply to the house. To prevent this, the air filter should be cleaned or replaced every month during the heating season.
• Bleeding Air from Radiators / Convectors - A hot water (hydronic) central heating system that has air in its lines or radiators will not function properly. The air will prevent the proper circulation of hot water through the system and, as a result, the radiators will not reach the required temperatures needed for heating the rooms as needed.

  To remove this undesirable air from the system, open the air valves at the convectors, radiators, and water lines. You'll know the air has been removed once the spitting stops and a steady stream of water flows out from the valve. When this happens close the valve.

• Thermostat Replacement - A faulty room thermostat will prevent the boiler or furnace from turning on and producing heat. If the boiler or furnace doesn't fire on after the thermostat is turned up, then it may be due to a defective thermostat.

  To test a thermostat, remove its cover and unscrew both low-voltage wires from their terminal screws. Then, carefully touch the ends of both wires together. This effectively "bypasses" the thermostat unit as if it did turn on.

  If the boiler or furnace fires on (burners ignite), the thermostat is defective and must be replaced with one of the same type and voltage. If the boiler does not turn on, then the thermostat is probably good and the problem lies elsewhere, either with the boiler/furnace or electrical system.