The hot water in the cold water pipe is due to the hot attic.
Hot water heater in attic freezing weather.
Still the tankless hot water heater can freeze if certain precautions are not taken when the temperatures drop below a certain level.
Exposed pipes both cold water and hot water in areas like a crawl space basement or attic can be covered with foam pipe insulation sleeves or wrapped with pipe insulation tape.
If there is a power shortage the heater might suffer from frozen water inside the.
It is more common however with outdoor installations.
By keeping the unit warm most freezing incidents can be prevented.
Routine maintenance should be performed once a year on your water heater and going into the attic is cumbersome and can either be really hot in the summer or really cold in the winter keeping an eye on the water heater on a daily basis is not as easy either adjusting the temperature is harder.
It s smart to insulate water supply piping exposed to freezing temp.
The weather has cooled significantly here in socal and i can tell the difference.
So far no leaks.
The greatest freezing danger to a tankless hot water heater is standing water that expands within the unit itself.
Your attic can easily reach temperatures of 120 140 degrees which is optimum for keeping the water in your tank sufficiently hot without using any energy.
The flow rate of it is 7 5 gallons per minute.
There is an electric pump next to the water heater that moves the hot water through the pipes delivering hot water quickly to most any faucet.
Most indoor and outdoor tankless water heaters have built in freeze protection against temporary winter temperatures ranging from 5 degrees fahrenheit to 22 degrees fahrenheit.
The heaters themselves need no protection from freezing weather as long as the electricity and gas are working.
Rinnai rl75en natural gas tankless water heater for cold weather use this tankless water heater is equipped with a freezing protection system.
This danger can apply to indoor models that are placed on an exterior wall.
It senses temperature change smartly and then takes measures automatically to protect the machine before it gets too cold.
Once my attic warms up after a few hours the next day the pipe thaw.
Now a secondary line of reasoning for placing a water heater in the attic is the high temperatures that occur in an attic particularly during the summer months.
Electrical heat tape can be applied to short spans of pipe in areas that may be particularly prone to freezing.