Be ware of over heating on Navien Combi units.
(Fort Morgan, Co. USA)
I am a licensed master plumber and have just finished the install of a Navien 240 NCB. This unit serves a residential home with hot water baseboard heat.
When the system was turned on and run tested I found that when the unit is in the heating mode set at 180 degrees for the baseboard heat and there is a call for domestic hot water (which is set to 120 degrees) I measured 138 degree water coming out of the domestic faucets for about 15 seconds. 138 degree water can scald very fast. I called Navien tech support and was told that Navien was aware of this issue and that I needed to put in a thermostatic mixing valve on the domestic hot water piping system to the house.
I reread the install manual and could not find any place where Navien had put a beware notice. I am very upset about this as I had to eat close to $500.00 labor & material for the install of the mixing valve. ( this job is a 30 minute drive from my shop 1 way) I would like to here from anybody else who has had this issue.
Click here to post comments
Join in and write your own page! It's easy to do. How? Simply click here to return to Navien.