Correct use of the heater

[Styggron]

Hello everyone.

On page 61 of the 172 manual it says to use the Engine heater for temperatures below -6 degrees

Quick question regarding the plug in heater before flying.

1. Do you need to pre plug the heater in a few hours real time before you plan to fly ? eg: If I want to fly 1pm real time. Should I fire up FSX at say 11am, plug in the engine heater then quit FSX and come back at 1pm and fire up FSX ? I guess this would simulate how it is done in reality ? Sorry I don't know how long the engine heaters need to be on to warm everything up.
2. Can you leave the engine heater plugged in if you're not going to fly for weeks or should you plug it in a few hours real time before your intended flight ?


At a guess. I would think I would need to plug in the engine heater a few hours before my intended flight or is it longer ? I don't know. Nothing much in the C172 manual about it.

So lets hear from the experts on here.
Thanks in advance everyone.

[flapman]

I've never used an engine heater in the sim, or in real life, so my response is an educated guess (hopefully! oh the joys of SoCal flying).

Pre-heater use should be temperature dependent, not time dependent. Your goal is to get the oil temperature up, and viscosity down to a point where it will circulate through the oil pump when the engine starts. I imagine the procedure is to put it on, then after about 10 minutes flick on the master switch and look at the oil temp gauge (then turn the master back off ). I imagine the recommendation is to wait until it's in the green arc, but it's probably good enough if the pointer is no longer pegged to the bottom of the instrument.

No idea, but I can't imagine it taking longer than 20 minutes.

I don't know how they do it for real, but I wouldn't leave an electrical supply connected to my airplane (which contains fuel) for long periods of time unsupervised. That sounds like asking for trouble. Freezing fuel will probably be the most pressing concern if it gets really really cold.

[Oracle427]

We have a Tanis heater on our 182 and it heats up the engine fairly quickly. We have a system that heats the battery, cylinders and the oil pan. An hour is sufficient if overnight temps have hovered remained around freezing. When the engine will be cold soaked with temps below -10C overnight it is best to leave it plugged in the night before a flight to ensure the whole block is nice and evenly warmed up. The system is supposed to raise the engine and oil temp to 33C +/- 10C over ambient temp after 6 hours of use. This equates to about 10C per 2 hours of use.

I wouldn't leave it plugged in indefinitely for risk of a fire due to a short or something else going wrong. For those fortunate enough to have hangars, there are relatively inexpensive systems that can be operated from a smart phone to turn the heater on and off in preparation for a flight. For the rest of us, we have to wait for access to a socket, bring a generator, or use a propane powered engine preheater.

From the Tanis site:
Tanis preheat systems are designed so you will achieve the maximum benefit from our system within 6 hours of use. Most of our data logging results show a 40 to 50 degree F increase within the first two hours of use.

[AKar]

Warm-up times depend on the heater's power, temperatures (both atmospheric and that of the engine's before heating), and on whether you've got some blankets and stuff to help to keep the warm in. In reality, sensible warm-up times are from an hour or two in mild weather, to perhaps six hours (in practice reads over night) for truly cold winter weather. I don't know how long it takes with A2A's heater, but if you fly plan to in cold weather next time, you can just leave it plugged after previous flight, no problem there.

In reality, there are some rather sophisticated heating solutions that monitor the temperatures and try to keep them constant, those are designed to be left on with airplane having insulating blankets over it, if wanted. To save power, their users often keep a modest +5 °C or so setting for longer periods, and beep the pre-heat function on a couple of hours before flight via mobile app. A regular electric engine heater...I don't think I would leave it on for longer parking in reality, albeit there is no technical reason typically why you couldn't.

Edit: Of course, if you don't want the engine to be thoroughly warmed, but consider warm pan of oil sufficient, reasonably powerful heaters take maybe 4 hours in cold weather to stabilize the oil temp while even after an hour it is warmed notably already. But your cylinder area would still be rather cold-soaked. Manufacturers of these things typically publish some test data on their web sites, of course your results may vary.

-Esa

[Styggron]

hmmmm

So looks like it really doesn't matter if I leave it on for 5 minutes or 3 weeks on the sim then.