srshaw
New Member
We had a tankless water heater (Takagi TM1) installed several months ago, and the plumber added a recirculating line to the farthest bathroom. We have been living with a couple of problems that I cannot seem to get to the plumber to address. The first is that when the heater shuts off and then restarts just seconds later, a 30 second "bubble" of cold water enters the hot water line after the hot water in the supply line is used. Since the heater is already hot and only takes 3 seconds to fire, this seems ridiculous. We checked to make sure that hot and cold are not cross-connected.
The second problem is that there is very low pressure/volume through the hot water system. The heater is rated at 9.6 GPM with the capacity to bring 6 GPM to 115 F, but when more than one fixture is on simultaneously the temperature an volume changes in any line are dramatic. The max amount of water that seems to move through the hot water system is 3.6 GPM. The plumbing is all the same, with the exception of the recirc loop, typically 3/4" with 1/2" stubbed out to fixtures.
Any thoughts/help?
The second problem is that there is very low pressure/volume through the hot water system. The heater is rated at 9.6 GPM with the capacity to bring 6 GPM to 115 F, but when more than one fixture is on simultaneously the temperature an volume changes in any line are dramatic. The max amount of water that seems to move through the hot water system is 3.6 GPM. The plumbing is all the same, with the exception of the recirc loop, typically 3/4" with 1/2" stubbed out to fixtures.
Any thoughts/help?