Jac04
Member
It's not lowering the heating loop supply temp when you are using domestic hot water (DHW). When you are using hot water, the remote displays the DHW output temperature and not the heating supply temp. During DHW use, the front of the unit will display the heating loop temp, which will be well above the DHW setpoint of 120F (because it is using the heating loop to heat the incoming cold water via a water to water heat exchanger - it doesn't use the main heat exchanger to directly heat the DHW).
If you are using DHW during a call for heat, the DHW gets priority. Then when you shut off the DHW, the unit will stop firing - that's what it is programmed to do to avoid overheating. The burner will not fire again until the supply temp drops to 10-15F (I can't remember the exact difference) below the supply set point. So, it sounds like it is doing what it is supposed to do.
The CH series do not have a 'boost' function.
If you are using DHW during a call for heat, the DHW gets priority. Then when you shut off the DHW, the unit will stop firing - that's what it is programmed to do to avoid overheating. The burner will not fire again until the supply temp drops to 10-15F (I can't remember the exact difference) below the supply set point. So, it sounds like it is doing what it is supposed to do.
The CH series do not have a 'boost' function.