Re pressurise the BAXI DUO TEC COMBI 28 HE A

Should be a filling loop on the cold feed

We had a 385 error code on a Baxi Luna Duo Tech 40 ga. The technician replaced the pcb (printed circuit board) for $453. This was in Missoula, Montana.

Check for water leaks on boiler and system check to see if pressure relief valve is not passing .when boiler is off

Silver flex hose may be the (correct) filling loop. There may be a valve at each end of it, maybe just one at one end.
Open the single valve slowly and LISTEN for the sound of water entering the system, and LOOK for signs of the pressure gauge rising.
On the dual valve version open the first, then open the second slowly as above. Close both valves when pressure is adequate. Adequate is determined by the specifics of your system, but note that more pressure DOES NOT mean better showers, etc.
It should only take a few seconds to top-up, any longer indicates a significant loss of fluid from the system.

is the boiler a combi if so have you checked the pressure. it needs to be at 1.5 bar 2 bar at the most . also check that the heat the boiler is producing is completeing the circuit on the heating if you have access to the pipe work there should be 2 or 3 22mm copper pipes. now turn the heating on and check which one is getting warm. the one that is is your flow and in about 2 to 3 min there should be one more pipe getting hot let me no if this is the case

Fault Code E160 on a Duotec Boiler is a fan fault.

Mine has just gone for the 2nd time! Gas engineer is on his way......

http://www.bhl.co.uk/uploads/article1477/Baxi%20Duotec%20HE%20Combi%20Boilers%2024,28,33,40%20Installation%20Instructions.pdf top the pressure by the filling loop

The boiler has a filling connection which uses a filling loop to connect the boiler to the mains supply for the initial fill and subsequent fills.
See the link below from the manual you can buy the filling loop connection online or ebay its a simple task to replenish the pressure. Worcester GREENSTAR 25Si Instruction Manual Filling The System

if your boiler is a combi re-pressurise locate filling loop and refere to manual