Braemar heater control unit showing flashing reset

It appears to be an Australian unit. We are in North America, so this link might work better for you. The first thing you can try is cutting the power for 5 minutes, AKA a 'power reset'.

https://www.google.com/search?q=BRAEMAR+BM320+reset

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To reset the service message on your Braemar evaporative system with a Magiqcool controller, you can try the following steps:

1. Turn off the power supply to the unit by switching off the circuit breaker or unplugging the power cord.
2. Wait for about 10 minutes to allow the controller to reset.
3. Turn the power supply back on.
4. Press and hold the "Mode" and "Fan Speed" buttons simultaneously for 5 seconds.
5. The service message should disappear and the controller should return to normal operation.

If the service message persists after attempting this reset, it may indicate a more serious issue with the unit and you may need to contact a qualified technician to diagnose and repair the problem.

Youtube doesn't show the Braemer specifically, but take a look at these and see if any of them work for you?

https://www.youtube.com/results?search_query=braemar+TE420+dishwasher+on+and+wait+light+flashing

Go to the outside unit and open the door that covers the electrical connections. There will be a reset button on one of the temp switches that needs to be pushed. Now you have to see why it needs a reset.

You need a technician to Diagnose the unit and to repair it.

We had the same problem in our Braemar TA522, failed to ignite, flashes ‘reset’, and shows fault code 07. Tried a few simple fixes over several weeks, could not resolve it. Then tried simply cleaning the two flame sensors (see photo) with a small piece of wet and dry paper, and the problem was immediately resolved! They are easy to access - remove the lid of your unit (turn power off first), and you will see these two sensors attached to the flame burners. Clean the right-angled rod at the bottom, apparently it builds up carbon over time. You don’t need to remove them, with a small piece of wet and dry paper you should be able to get underneath the burners to clean them.

I had the fault code 05 (spectrolink controller) recently on a Braemer TG420 ducted heater. The heater would start and cut out on high temp as the room fan was not starting. I checked under the house and found the cable fitted to the return air thermistor had been chewed. I repaired the section of cabling and restarted the unit and it worked fine. Fault Code 05 is to do with the Thermistor in the return air duct.

it gets its power from the unit via the data cable. go on the seely international website or the braemar website and they can put you in contact with another dealer in your area. get it fixed while still in warrenty.

Look for the error code on the right hand side of the display above the zone section and below the actual temp displayed.... refer to:
http://www.braemar.com.au/PDFDocuments/Section8_ServiceTroubleshoot.pdf

The Braemar heater I have is wired directly to the control unit. The only way to reset the time is to turn of the heater for 5 minutes - the remote display should clear, and turn it back on (takes a minute for remote to come back on) the time will be flashing - use the Up and Down arrows to set the time, and SET button to set the day of week.