Low Return Temperatures

There are several possible causes for Low Return Temperatures

• Air in the return lines. The hot water system needs to be flushed out after any repairs because air will get into the lines. Most apartment dwellings have a bleed valve for that purpose.

• Pumps can also become damaged by air in the lines if they are water cooled and an air lock prevents water from cooling the pump.

• Unbalanced returns -when more than one line comes back to the heater room sometimes most of the flow goes through one side only, leaving the other return line to become cold.

• Return line feeding directly into the hot water tank at a point where mineral deposit buildup can cause slowing of the flow.
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• Damaged mixing valves that bleed cold water into the hot water system are a constant threat and cost many dollars in additional gas and water costs if they are not replaced.