Condensation on windscreen and side windows

[wild camper]

2017 Custom Limited with fixed bulkhead behind driver.
I think the Custom is great except for this annoying problem that can become dangerous.
I can be driving along with a clear windscreen and suddenly all the windows mist up without warning.
I lose clear visibility until I can wipe away the condensation because it takes too long for the heater to clear the screen even on full blast.
There’s no leak in the cab, the A/C is not on, I even have bags of silica gel in old clean socks placed on the dashboard.
The van is garaged at night.
Anyone else had this problem?,and any suggestions how to prevent it

[Dementinator]

Theres your problem, the AC is not on, I find the AC more useful in winter than summer, keep the heater set to demist, the fan speed on low and AC is always on, never mists up, turn off AC and instant cataracts.

[wild camper]

Thanks Dementinator, I’ll give that a try, in the past I’ve rarely used A/C because it adds to the fuel consumption but it will be worth it if it keeps the screen clear for safety reasons

[Mike]

I’ve rarely used A/C because it adds to the fuel consumption

It's hardly noticeable, more noticeable at this time of year is the mpg difference as garages introduce their winter diesel.

[Altransit]

I’ve rarely used A/C because it adds to the fuel consumption

It's hardly noticeable, more noticeable at this time of year is the mpg difference as garages introduce their winter diesel.

The A/C hasn't worked on my Mk7 since I bought it in 2015, until I had a new compressor fitted earlier in the year, and I haven't turned it off since.
As said, it's great at keeping the windows clear, and the overall fuel consumption, which I monitor quite closely, hasn't changed at all.