You can leave it on as long as you want.

A stone chip cracked my windscreen soi replaced it witha heated screen, I have both now.

I've tried the ultimate experiment and left the HotFrog engine preheater running all night. Temperature outside was low to 0°c by early morning although there was little frost. When I parked up and started it running at 6pm the engine temperature was 60°c, two hours later it had dropped to 50°c...

It is 2.2w. The results are good enough as the windows have cleared quickly which is what I wanted, I don't need a fully preheated engine. The ice wiped away by the wipers and some demisting performed before turning the blower on. Drivers side almost clear a couple of mins after putting the...

I set the timer for 7am and it is now 8:50. It is frosty so a good test. The windows have started to defrost before I've started the engine, but it has only got to about 40°c. I was expecting it to heat up quicker but then it is cold and that's a big engine block to heat up.

Socket is just a lead under the bonnet, I intend to make a flap for the socket in the false air intake which is on the side where the power is in the garage. Need to time how long it takes to warm up, will report back. No timer, I'll use one on the socket.

Yes but it is designed to mount onto the back that is facing down at the moment. The pipes are holding it OK for now but I intend to make a suitable bracket, the supplied bracket is screwed on so I can unscrew that to mount my bracket.

Yup this is why I rushed to do it tonight.

Finally in and running

Installed and running.

I want to warm the engine up as well as providing heat for the blower. Running a power lead is not a problem.

Anyway, how could you shoot or not get up and walk these two, look at their faces....

I think shooting the dogs is unnecessary, I could just lay in without shooting them?

Finally I know where the pre-heater is going to be installed and I am confident this is correct. I sent this image to Eugen at HotFrog who has been very helpful! He confirmed that this is the best place to mount the HotFrog Truck and I've managed to source suitable pipes. The heater matrix...

When I emailed the company for advice they posted this link to a video.