Mike Shurben Heating Ltd.

Gas Appliance Specialist

Providing quality work, competitive prices and reliable service

Serving Ottawa Ontario, and outlying areas

Phone: 613-266-5452Fax: 613-257-8844
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Water Heaters

Direct Fired Storage Heaters

These are the most common type of water heater and are available in electric, natural gas, propane gas, and oil fired. These water heaters are sized to provide water for the busiest hour of the day. Electric water heaters have the longest recovery time while oil fired water heaters have the fastest recovery time. The pressure and temperature safety relief valve should be test fired yearly to help flush out any rust and lime build up on the valve. A bucket should be placed under the discharge pipe and the valve should be actuated while standing out of the line of fire from the hot water that will be discharged. If the valve won't open to discharge water or won't close after the discharge of water then it must be replaced. The discharge pipe must never be capped.

Depending on installation circumstances, there are several venting options available. If the water heater can be located close to an outside wall then a direct vent provides the safest venting option against house depressurization and is quiet when operating. The power venting option is good when the water heater vent has some distance to go before exiting through an exterior wall, but has some noise associated with the ventor motor. In older homes that are not tightly sealed the older style naturally vented water heater works fine and is also quiet when operating.

Direct Fired Instantaneous Heaters

These water heaters have been used in Europe, Japan and China for many years. They are considered to be of higher efficiency than storage type heaters because there is no water storage and thus no standing heat lost. When upgrading from a storage type heater to an instantaneous type heater, sizing the unit is much more critical. Typically these units have modulated gas burners that have higher BTU inputs than the storage water heater they are replacing. This quite often means the existing gas piping is of insufficient size and will need to be changed to larger piping. For example a 40,000 BTU 40 gallon storage type water heater may be changed for a 20,000 BTU to 200,000 BTU modulating instantaneous water heater. The gas piping has to be able to supply the high end of 200,000 BTUs. The instantaneous heaters basic operation relies on the measurement of water flow through the heater and adjusts the amount of BTUs required to heat that measured flow rate.