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Low budget preheat

Is anyone using the Reiff cellphone switch (or a similar switch) to control their preheater? Would you recommend?

Do those cellphone switches typically have decent reception in a closed hangar?

Thanks!
 
i have a milkhouse heater set up which i occasionally use but a few observations
i have never left it unattended as i am always afraid of some sort of seizure [mouse nest] and fire. i know guys that have them on timers but i myself wouldn't do that.

and i added another flexible tube[i used plastic dryer vent] to pull the air from the cowl back to the heater. when its really cold you are really getting a temp boost by reheating already warmed air.
 
I was going to build a preheater like Geico's but this morning I wanted to fly and it was 14 degrees out when I woke up. I borrowed my wife's hair dryer, stuffed it in the right side air inlet, plugged the left side with a towel, put a blanket over the cowl, and checked the oil temperature - 27 degrees. 40 minutes later I checked the temperature and it was 57. I was astounded. When I started the engine (and it started on the 2nd or 3rd blade) I watched the oil temps drop to 52 in perhaps 30 seconds and then start climbing. My initial reaction is the cold soaked engine block and components warms up quickly with the engine running and a concern mentioned earlier doesn't seem to be an issue at these temperatures.

Now I'm thinking twice about building an engine preheat system. I was really impressed with the results I got using the lowly hair dryer.
 
Of course SOME of us can just go to Autozone or O'Reillys and pick up an automotive block heater for a few bucks. Sorry guys, I could not resist.
 
The hair dyer trick works great. I have been using my wife's 1750 watt hair dryer for three years now. Its real easy to take along with you on a cross county flight .

It really doesn't take very long to be ready for start.


Brad Stiefvater
Salem SD
 
This season we've been very much enjoying my sump heater plugged into a relay controlled by a Raspberry Pi in the hangar which polls our google calendar for an event which defines heat on/off and sends an email with the state change. Happy geek.
 
I have the Reiff oil pan heat pads and a ceramic 'brick' heater connected to an aluminum dryer vent duct going up into the exhaust opening in the cowl. I plug the cooling air inlets in the cowl and put a blanket over the cowl in my hangar. This is plugged in to one of the circuits(there are two) of my Switch Box that is activated with a cell phone call or text. I also have an iPad/iPhone app for the switch box that only requires one button push. I try to remember to activate it at least two hours before I arrive to fly. I have the limit set at four hours in case I decide not to go and forget to turn it off (with the app/phone). If it runs 4 hours before I fly, the oil will be at 90*, and the cylinders and battery will be nice and warm in my RV8.
 
i have posted before that i use the stick on silicone pads but would not use a ''milkhouse heater'' or any heater that gets red hot or uses a fan unattended.
yesterday i was in my hangar and i do use several milkhouse heaters in my shop to get it warmed up before the baseboard heater takes over. first time ever, my milkhouse heater goes into this mode where the fan spins slowly, stops, spins slowly again......and on and on. the elements continued to put out heat. this was after it had run normally several minutes. confirms my thoughts that i would never run these things unattended.
 
Same here with the milkhouse heater I used to use before the Reiff. When the fan motor was cold, the fan motor sometimes would not spin the fan blade.

Also, if you must use a milkhouse heater, elevate it by placing on a stool or something. Do not place the milkhouse heater under the plane. Had a hangar fire at KDVN that destroyed the plane. Theory was gas was dripping into the ducting.
 
Installed the Reiff Rotax system during the condition inspection last month. Very effective. Flew on a 30 F deg day, oil temp at startup read 94 deg F. Only needed 5 minutes or so of warmup compared to the 15+ minutes usually needed without the preheat at that OAT.

Plan on getting the cell remote switch they offer. I drape a blanket over the cowl and plug the air intake holes.
 
What Size (W x L) Pad Heaters?

I want to add two low-wattage silicone heater pads on my 12 to preheat both the engine crankcase and oil tank. I will use a cell phone switch to turn on the heat a couple of hours prior to flight. Question – does anyone know what size pad (L x W) will fit nicely on the bottom geometry of the 912 crankcase? Also, what size pad (L x W) that will partially wrap around the oil tank?
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Jim - -

I would highly recommend the REIFF pre-heat for the 912 engine. It has an FAA approved number on it. Works very good. You need to warm the oil tank also. If not, you will be feeding in cold oil the second it starts. You will burn more gas waiting for the oil in the tank to warm. Also, if you don't have it already, install the Thermostasis oil therm. Speeds up ready to fly oil temps much quicker. I feel they both pay for themselves in time.
 
I want to add two low-wattage silicone heater pads on my 12 to preheat both the engine crankcase and oil tank. I will use a cell phone switch to turn on the heat a couple of hours prior to flight. Question ? does anyone know what size pad (L x W) will fit nicely on the bottom geometry of the 912 crankcase? Also, what size pad (L x W) that will partially wrap around the oil tank?
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I 2nd the reiff system for the rotax. No measuring or cutting, it's ready to install and simple at that.

2 hours is not long enough with any preheat system like reiff or tanis. In cold temps below 40f I turn it on at least 12hrs before flight. Reiff has a thermostat that shuts off at 150f. I've never seen oil temps above 110 on the skyview before starting with the system plugged in overnight.
 
I want to add two low-wattage silicone heater pads on my 12 to preheat both the engine crankcase and oil tank. I will use a cell phone switch to turn on the heat a couple of hours prior to flight. Question ? does anyone know what size pad (L x W) will fit nicely on the bottom geometry of the 912 crankcase? Also, what size pad (L x W) that will partially wrap around the oil tank?
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Installed EZ Heat system several years ago and it works great (when I remember to put the timer on and run it for several hours). One pad on lower half of oil tank, other one on bottom of block (pad fits fine on Rotax per your question if you are using the EZ Heat pads in your picture). On coldest days I will also place hair dryer on left cowl air intake when arriving at hanger which adds a little more warmth to the top of the engine via the shroud.

FYI for EZ Heat - Recall that I contacted the manufacturer to source one that had detachable electrical plugs on the pads to make removing the oil tank easier. Answer - for safety regs they did not offer that. So I just installed my own. I don't physically remove the tank from the engine very often (use drain plug), but if you don't made that mod, the power wires are fairly short making occasional Rotax oil tank cleaning more awkward to complete.
 
I also installed the EZ-Heat system (pictured above) in my RV-12 three years ago. It is inexpensive, easy-to-install, and works well. Granted I live in relatively balmy northern California (winter lows @ 30 degrees F). I typically use a timer to provide about 2-3 hours of pre-heating and all is toasty and ready to go. I also place an 18" Golden Rod dehumidifier tube in the cockpit during the winter to keep the cockpit warm and drive out moisture -- not really sure as to its effect, but it is easy to do.
 
Anyone have a picture of how the EZ Pad is mounted to the RV-12 oil tank? Is the pad flexible and allows curvature to conform to the tank? I'm leaning toward EZ Pad installation with cell phone remote switch/timer.

Thanks in advance...
 
I have no pictures, but one pad gets easily glued onto the exposed lower front portion of the oil tank. The pad is sufficiently flexible to match the curvature of the tank. The second pad gets glued to a flat portion of the bottom of the crankcase. The "glue" they provide has worked well for me over the past 530+ hours.
 
I received my CL1-GSM Controller from eBay - $29.99 incl shipping. The relay switch is controlled remotely with a cell phone by simple text messages.

I bought a TracFone SIM card with a $15 pay-as-you-go plan, which covers 30 days use. I will refill the card for October & November and then again for March & April. I don’t plan on flying the plane during the heavy winter months. The SIM card must be for T-Mobile network. T-Mobile is only carrier that currently supports a 2G cell network, which is what the CL1-GSM uses. T-Mobile will continue to support 2G until Dec 2020 at which time they will shut down the network and I will need to replace the switch with a unit using 4G network. No problem, for $30 this cheap relay switch works a charm…

The relay switch allows you to set a master number and user-selected password so only your cell phone will control it. No other phones or robo calls can operate it.

The relay switch sends confirming messages to my cell phone to indicate state of the relay. For instance… “State is ON” or “State is OFF”. The unit can also turn on for a predetermined time, which is ideal for the engine pre-heater. I will initially set the timer to run for 60 minutes and adjust that time as conditions warrant.
 
Suggestions are good.

My typical use is (1) stop for a cup of coffee, (2) arrive at hangar and plug in HPS (Hairdryer Preheat System TM :)), (3) drink coffee, preflight, do small chores that you've put off, chat with hangar neighbors, (4) 45 minutes later, start engine. I would not recommend operating this system unattended.

TODR

I think you are missing the restroom break in your workflow. I would not fly with out a pre flight pit stop with all of the coffee you drink ;)
 
Update to my post above... I just found a less expensive cell phone plan offered directly by T-Mobile. You buy the SIM card directly from T-Moble for $10 (T-Mobile®Prepaid Mobile Internet 3-in-1 SIM Kit). Then a 30 text/month pay-as-you-go plan only costs $3/month.

It's almost free... :D:D:D
 
Update on Cell Phone Switch?

Update to post #71 above? The CL1-GSM has proved unreliable when positioned at the hanger. I think either poor proximity to cell tower or 2G cell network is causing the problem.

I have bought a 4G cell phone switch again on eBay for $149. Vendor is Relay-Supply in Saskatoon, Saskatchewan, Canada. Delivery is three days. Unit works excellent on my $3/month T-Mobile SIM card. This unit has ability to monitor quality of connection to the cell tower. At the hanger with external antenna the cell connection is 24/30.

https://www.ebay.com/itm/4G-GSM-Hig...e=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2649

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Metal siding and roofing can interfere with or block cell phone signals.

Actually I think the metal is acting like a ground plane with antenna mounted outside. Signal with same antenna inside the hanger was 17/30 and 24/30 where it is installed on the angled drip edge.
 
In the US T-Mo is rolling out an extended range LTE tower set, BUT some older devices like my Samsung Note3 will have NO service on the new towers.
 
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