2005 Fleetwood Expedition 38N engine heater block

[mcflop]

I have 2005 Fleetwood Expedition 38N with the engine block heater switch on the side of the bed pedestal. The switch lights when turned on and the light goes out when turned off with no change in amperage use.
How do I determine if the block heater is working properly?
The temperature here is 75 degrees. Is there aa thermostat that keeps the heater off when not cold enough?
Thanks
McFlop

[will stevens]

My engine heater is plugged in inside the electrical bay and the switch inside turns the plug on and off. I keep mine unplugged until needed as it is easy to bump my switch.

[GBDTN]

You should be able to see the top of the heater plug on the side of the block. On mine the wire comes down under the bed to the battery bay and straight over to the block. I used some metal plumbing hanger to cover the switch because of accidentally bumping it off and on.

[jbrinsfi]

On my '07 Excursion with the same block heater set up, I see about a 10 amp draw when the switch is actuated. I don't think there is a thermostat on the block heater circuit but I am not certain of that.

[mcflop]

The light on the switch by the bed comes and the plug appears to be plugged into the block but no amperage change when turned on. Ill have to check further. Maybe the block heater is bad.
Thanks
McFlop

[Jthigh]

I just bought a new block heater for my Cummins ISL400. It measures 15 ohms. You can check that wherever it plugs in or right at the heater element. If your element reads ok then you may have wire or switch issue. You can also just check to see if you get 120 VAC to the heater itself.

[Jthigh]

Ours doesn’t have a T stat either. My AC cord goes directly to the element.

[JLWoodward]

The switch on the side of the bed just turns an outlet in the closet on. The block heater is plugged into that outlet in the aft closet. Make sure it's plugged in and also make sure the outlet has power. The light on the switch by bed just means switch is on not that outlet is powered so double check it. If outlet is powered, and heater connected, and you still have no amp draw then the heater is bad. It's not thematically controlled it's just on or off. The heater itself is basically just like the heater elements in your homes water heater. You can see the heating element from left aft ext door, house battery area, heater is in side of block in water jacket

[KF5UMC]

According to the specs, the heating element is 120 vac, 750 watt. Current draw should be about 6 amps. 15-20 OHM resistance. Turn it on, wait a 30 minutes - 1 hour and feel the element housing at the engine block. 750 watts should be unconformable to the touch. And as mentioned before no thermostat.

Our switch location allowed the AC element switch to get kicked on sometimes for DAYS! I installed a covered, latching door AC box and no more problem.

[mcflop]

Thanks for all the info.
I have some checking to do to see if I have a bad heater element.