Broadway battery drain

I have a 10 day old Broadway. I previously owned 2 others. I've been off EHU for 2 days and last night had warning of low battery power. 100w lithium. I couldn't turn off the alarm ( can you?) so switched to vehicle battery. My controller said 1amp drain with everything I could see turned off. It was frosty so was it tank blankets? Previous van had switches to turn on or off. I can't find any on this van. Are there any? I believe the blankets should not come on if empty tanks. How to turn off?
Side issue is fuse 10 has blown twice. I have no owners information book and no sticker on the EC700 unit. Which fuse is which?
Owners information supplied is very scanty and often out of date.

As your van is brand new, I think you need to speak to your dealership. They seem to have omitted to give you a handbook and need to sort things out for you.

Btw, your avatar still shows a 2018 model.

Have you looked at the Owner's Manual that's available on the A/S website?

If that's out of date then A/S need to be told about it, because that's what every new user should be provided with.

Thanks. I was supplied with a 2023 instruction book. It is out of date. It describes different items to what is fitted in my van. I checked the Autosleeper website for a manual. It's the same 2023 out of date one.

Philip John wrote:Thanks. I was supplied with a 2023 instruction book. It is out of date. It describes different items to what is fitted in my van. I checked the Autosleeper website for a manual. It's the same 2023 out of date one.

So it's a bit like your profile, out of date showing the incorrect van year  

The AS Coachbuilt handbook is no longer model specific and 2023 is the current issue. You should have been given manufacturers handbooks for all of the fitted equipment including the Harmony handbook https://www.manualslib.com/manual/1640680/Auto-Sleeper-Harmony.html that includes technical information regarding the EC700.

Fuse 10 is said to be for the En Route/Entry light which I believe is the strip lighting system in the overhead lockers.

The tank heaters need to be switched on on the EC700 and will only operate in a specific temperature range and if the tank contains fluid. The 12v current draw will be at least 4A so that is not the problem here. Power to the various apparatus control boards will be at least 1A so that sounds normal.

What 12v apparatus and for how long did you use it over the two days?

I only used heating (fan draws c. 0.5A) lights and the fan in the fridge. No TV. No radio. 
I've been told by the supplier that it takes 4 days to charge the battery.  That goes against any Google gurus ideas or amperage arithmetic. When plugged in it accepted 19A, reduced to 14A after a day. Two days later it says it is not accepting any charge and was holding 14.00A on EHU. I've unplugged it an hour ago and will monitor what happens next.

I suggest you read the information on charging Lithium Batteries in the picture below - yours is not right.

The Truma Combi can take up to 5.5A at 12v and averages out at 1.5A.

If as you state in post one, you have a (then) 10 day old van then there is something drastically wrong with the electrical system so get it straight back to the dealer you bought it from.