Navien Boiler

[David1001]

Hello..

We have installed a new Navien Blue Flame oil boiler. We are using the Hive hub and controller to control and program the boiler. However, although we can trigger the boiler to turn on and off etc via the controller, it seems to be ignoring the schedule we have programmed into the Hive.

For example, on the Hive, we scheduled the boiler (CH and DHW), to be off during the night, and to come back on at 8.30am. However, the boiler is firing up during the night and the radiators are warm.

I have attached 2 photos of the boiler and hive interface screens

The Hive shows the current time as 5:15 am, and the CH and DHW both scheduled to turn on at 8.30 am. The current target is off (0 degrees), the actual temp in the house is 21.9 degrees. Its Scotland and winter, so the temperature should no way be 21.9 degrees in this house (its that temp because the boiler keeps coming on).

Looking at the Navien interface screen. Its shows CH currently off (it just went off but was on for around 5 minutes previously), the DHW and its temperature show no information, and likewise, the house temperature icon shows no information.

So something is clearly amiss here. I would expect a reading for the house temp and the DHW temp and program i.e. OFF, ON or SCH ?

Does anyone have an idea of what might be going on here?

Thanks in advance.

PS: Other than this, the boiler is great. It is quiet, and heats the house and water very well. No smell at all of oil. Just needs this final mismatch resolved between the hub and boiler.

 

[stem]

Is there a remote frost stat somewhere? They are usually located in areas where there is a risk of pipes freezing, such as an outbuilding or roof space. They are installed in such a way that they override the other controls and turn the heating on to prevent freezing. If there is a frost thermostat somewhere, maybe it is set too high and coming on unnecessarily.

Normally there should also be a limit thermostat (pipe stat) clamped on a pipe somewhere so that the system just gets warm to prevent freezing and not hot as it would when the heating was scheduled to be on.

You would be looking for something like this

Although sometimes the pipe stat isn't fitted, and the radiators do get hotter than they should.

 

[David1001]

Hi, thanks for your reply. To be honest, I dont know if those thermostats are present, but I will forward this information to the engineers that fitted the system to check that out.

I've come to the (perhaps wrong) conclusion, that the boiler is either completely ignoring the schedule settings from the Hive, or the boiler is missing some vital information that allows it to run off the schedule. For example, the boiler isn't showing an indoor temperature reading (just two dashed lines), and also isn't showing a hot water temperature reading. I'm wondering if it has been using some default values to just maintain a base level temperature for CH and DHW water temps..

Thanks again..