Endurance EBP insufficient DHW

adkap

I moved into a brand new condo last month that came with an Endurance EBP boiler. It seems to be working incorrectly. If I run the hot water, it will come out hot for a minute or two, but then get ice cold. After another minute it's back to hot, and stays there for 10-15 minutes, then repeats.



From the LCD display, it appears as though the pump turns on after a few seconds of water draw. However, the gas burner doesn't ignite, even as the temperature drops down into the low 160s. The set point is at 190 (default), so the burner should kick in at about 167 (right?) Instead it ignites once the supply temp dips before 150. From the manual, I know that it's kicking into tank fill mode. Once in tank fill, the hot water lasts for a while because the tank takes a long time to get to the shutoff temp while I'm running the bath tap.



The manual is unclear, but I think the burner is supposed to turn on low fire as soon as it detects a DHW draw... well before the temp drops below 150 and the supply is freezing cold!!



I went into one of the vacant units in the building and looked at their boiler. It seems to be piped the same, and that boiler ignites the burner almost as soon as it senses DHW draw.



Any thoughts??

adkap

Check the flow switch

George from Laars contacted me pretty quickly and we determined that the problem was an incorrectly installed flow switch on the cold inlet. The boiler couldn't detect domestic hot water demand because the installer had put the flow switch in sideways. Rotating it to the correct orientation fixed the issue immediately!