Broken Wires on Tannis Heater

[Jay Honeck]

So we failed the mag check last Wednesday. The right mag dropped 300 RPM, and stubbornly would not clear itself no matter how hard/hot/lean I ran it. The JPI engine analyzer once again paid for itself by showing me that it was the #1 cylinder misfiring.

I taxied back and shut down. We decowled, fetched my tools, and pulled the plugs. The bottom plug had a chunk of crud stuck between the electrode and the body -- a first, on these uber-expensive fine-wire plugs. Lacking the correct tools to properly clean the plug, I made do with a paper clip and some fine sand paper, being careful not to change the gap.

While we had the cowls off, I took the time to inspect the engine. As usual, it was covered with a fine layer of oil. We have chased a tiny oil leak for years on this engine, without success. So, we started cleaning 'er up.

Mary said "Whoops -- this isn't supposed to be disconnected, I'll bet." I looked and on the bottom of a cylinder was a plug with two wires going into it. One of the two was just hanging, and you could see where it was broken off flush with the plug. Crap!

Not knowing what it was, I checked the adjacent cylinder. This also had a little plug, but both wires were sound. The next cylinder had the same plug -- but when I touched the wires, one of them was not connected to anything! WTF?

Tracing these wires back was a huge PIA, but we eventually followed them all the way back to the 110 volt outlet/inlet on the top of the engine for our Tannis heater. Apparently these little plugs are the cylinder heaters (I knew we had both the sump and cylinder heaters), and half of them are now inop due to vibration breaking off one or both wires.

Not that this will matter to us here in the Deep South, where preheating is unneeded -- but I wonder if there's any kind of service bulletin on these things? It sure seems like a laughably bad design.

Anyone know?

 

[bbchien]

Many moons ago, Jay, I had a look at the Tanis bolt heater and bought Bob Reiff's system.

Agree 100%. Crazy design.

 

[gismo]

Many moons ago, Jay, I had a look at the Tanis bolt heater and bought Bob Reiff's system.

Agree 100%. Crazy design.

Tanis is now based at my home drome but I also like the Reiff system better.

 

[kmead]

I haven't seen any service bulletins on the broken wires, but it is a common problem on the Tanis probes. I have Reiff on the Malibu and Tanis on the 172. I always plug the systems in at annual and check all of the elements. Use a heat gun, you wont believe how fast they get up to temp.

Kevin

 

[flyingron]

I've got a Tannis, but it uses the cylinder heaters that are blocks that are pulled up against the cylinder by replacing one of the valve cover screws with a thinner bolt. I've got no problem with things brewing. It's pretty easy to tell if the thing is working properly. Plug it in for a while and put your hand on each cylinders (and the blocks where the pads are attached).

 

[Jay Honeck]

I don't think there's any way to repair the wires -- they are broken off flush with the plugs.

Replacing them looks simple -- unscrew old plug, screw in new one -- but if I replace them, how does one splice them into the wiring? Or does the install require that a single continuous wire must go back to the outlet?

I don't need preheat down here in the land of sunshine, but I like having everything on my plane in working order.

 

[kmead]

Normally the Tanis heating elements have 2 insulated spade connectors within 3" of the heater. If they are gone I will crimp on new matching terminals. Normally there is a harness to connect all of the elements to the plug.

Kevin

 

[Jay Honeck]

Normally the Tanis heating elements have 2 insulated spade connectors within 3" of the heater. If they are gone I will crimp on new matching terminals. Normally there is a harness to connect all of the elements to the plug.

Kevin

I didn't see any spade connectors -- but perhaps they are further upstream.

Anyone know the best place to buy these little buggers?

 

[wsuffa]

I pulled the Tanis out of my plane shortly after I bought the plane. 2 cyls with broken wires - not worth repairing. Reiff is a much better choice.

 

[N801BH]

Virtually every one posting on here has either had a failure or heard of one concerning the Tanis product. It is a FAA certified item, not some experimental stuff.... I guess my comment is..... Why no service bulletin about this flaw ? FAA asleep at the switch ? .

 

[wsuffa]

Virtually every one posting on here has either had a failure or heard of one concerning the Tanis product. It is a FAA certified item, not some experimental stuff.... I guess my comment is..... Why no service bulletin about this flaw ? FAA asleep at the switch ? .

It doesn't represent a safety hazard.

 

[N801BH]

It doesn't represent a safety hazard.

Until it burns down a row of T hangars somewhere...

 

[gismo]

Virtually every one posting on here has either had a failure or heard of one concerning the Tanis product. It is a FAA certified item, not some experimental stuff.... I guess my comment is..... Why no service bulletin about this flaw ? FAA asleep at the switch ? .

Most engine heaters are not "certified" and since they don't have to operate in the air all the FAA cares about is that they don't cause problems.

 

[denverpilot]

Spade connectors. Ugh. Crap.

 

[SCCutler]

Spade connectors. Ugh. Crap.

Yabut.

It's not the spade lug connectors that fail; the wires break off flush with the head of the heating-element bolt. There is no effective strain relief where the wires enter the heating unit.

The heaters work well, though (!).

 

[N801BH]

Most engine heaters are not "certified" and since they don't have to operate in the air all the FAA cares about is that they don't cause problems.

That's interesting. All the A&P's and IA's out here will NOT install any heating device in a plane unless it is FAA approved... A loose and dangling wire waiting to get caught in a critical part must be OK with the FAA in any certified aircraft... You have me on a mission now looking for the criteria on how the FAA views heater installs. I wonder if Reiff and Tanis tout the fact their units are approved......

Be back when I google it.:wink2:

Ben.

 

[N801BH]

I'm back..............................

Taken from the official Tanis website. QUOTE """

Tanis is the recognized world leader in aircraft preheat systems.

Complete Aircraft and Engine Preheat Systems for your Piston, Turbine or Rotorwing Aircraft

For 37+ years, Tanis has been increasing the utility and safety of aircraft by applying heat to critical engine and drive train components prior to flight. Systems are available for a wide variety of piston and turbine engines for fixed wing aircraft and helicopters. Tanis systems are engineered for long life and safe operation, and are constructed from high quality aircraft grade components.
Tanis stands for the most technologically advanced systems for aircraft preheat. A Tanis system is the only solution to provide heat to all critical engine components. At Tanis, we understand temperature envelopes, conditions and increased demands of cold weather operations. Tanis Aircraft Products operates an FAA PMA approved manufacturing facility.

UNQUOTE........

And from the Reiff website. QUOTE """"

FAA-PMA Approval
​

"FAR 21.303(a) No person may produce a modification or replacement part for sale for installation on a type certificated product unless it is produced pursuant to a Parts Manufacturer Approval (PMA) issued under this subpart."​

Our products are FAA Approved by a PMA granted in 1995. To obtain a PMA we had to obtain engineering design approval from the Chicago Aircraft Certification Office, and approval of our production system and fabrication inspection system (quality control program) from the Minneapolis Manufacturing Inspection District Office (MIDO). To maintain the PMA, the FAA inspects our facility and audits our fabrication inspection system. We have received a clean bill of health every time.
FAA classifies our engine heaters as minor alterations, so an STC or Form 337 is not needed.​

Following is the text FAA has instructed us to place into our installation instructions:

UNQUOTE""...

Seems the FAA wants some kind of quality control over these products or both manufactuers could save a ton in not meeting FAA specs.. I could be wrong though.

Cheers.

Ben.
​

 

[SCCutler]

By the way, I've had only one fail since I owned my bird; looks to me like the key to longevity is securing the wires such that they don't move around much.

The heater elements are not what I would call, "cheap." I sure like having them there, though.

 

[N801BH]

Most engine heaters are not "certified" and since they don't have to operate in the air all the FAA cares about is that they don't cause problems.

Ok.... After digging deeper and googling I cannot find any more aircraft engine heaters other then Tanis and Reiff to see if they are FAA blessed. Fill me in,,, what brands have I missed?

Thanks in advance.

Ben.

 

[JGoodish]

Ok.... After digging deeper and googling I cannot find any more aircraft engine heaters other then Tanis and Reiff to see if they are FAA blessed. Fill me in,,, what brands have I missed?

Thanks in advance.

Ben.

Honestly, I'm not sure that this is as big a deal as you're making it out to be. These heaters aren't a safety threat, they are not a fire threat, and it would take a really, really botched installation to cause any operational problems with the aircraft. In the latter case, I suspect that the competence of the A&P installing the system would be more of a focus than the system itself.

I have had a Tanis system on my Cherokee for probably 10-12 years, and haven't had any issues with broken wires. My system does have insulated spade connectors within 6" or so of each element, so that the elements may be easily disconnected from the main harness. My installation is also secured pretty well all along the harness, with just enough slack at the elements to avoid straining the element wires.

I knew about Reiff before I bought the Tanis, though I had never seen either system first-hand. I now suspect that I would prefer the Reiff design, but certainly not enough to throw out a Tanis system that is already installed.

I believe that Tanis sells replacement parts through their web site.


JKG

 

[N801BH]

Honestly, I'm not sure that this is as big a deal as you're making it out to be. These heaters aren't a safety threat, they are not a fire threat, and it would take a really, really botched installation to cause any operational problems with the aircraft. In the latter case, I suspect that the competence of the A&P installing the system would be more of a focus than the system itself.

I have had a Tanis system on my Cherokee for probably 10-12 years, and haven't had any issues with broken wires. My system does have insulated spade connectors within 6" or so of each element, so that the elements may be easily disconnected from the main harness. My installation is also secured pretty well all along the harness, with just enough slack at the elements to avoid straining the element wires.

I knew about Reiff before I bought the Tanis, though I had never seen either system first-hand. I now suspect that I would prefer the Reiff design, but certainly not enough to throw out a Tanis system that is already installed.

I believe that Tanis sells replacement parts through their web site.


JKG

Maybe I am being a bit paranoid but this recent fire has alot of us out in cold county concerned about electrical fires....

http://times-news.com/local/x2114751836/Airport-hangar-fire-destroys-9-planes

Just look at the pics of those melted planes...

Just this month a few T hangars tenants were complaining about tripped circuit breakers in their hangars.... So a quick search of all the hangars revealed some very disturbing things. Let me rephrase that " some very SCARY things"... I will post more about the details when I can confirm them... Needless to say when a fire breaks out in a row of T hangars one of the first things that happen is the power fails and NO hangar doors can then operate.... I have nightmares about my toy sitting in its hangar and having a fire break out in an neighboring hangar and no way to pulling it to safety... Personally I don't want to lose my plane to a fire... Sorry for me sounding so uptight.

Ben.

 

[JGoodish]

is the power fails and NO hangar doors can then operate.... I have nightmares about my toy sitting in its hangar and having a fire break out in an neighboring hangar and no way to pulling it to safety... Personally I don't want to lose my plane to a fire... Sorry for me sounding so uptight.

I don't want anything bad to happen to my aircraft either, but I carry adequate insurance so that such a worry doesn't keep me up at night.

Regarding hangar fires, based on what I've witnessed folks keep and do in airport hangars, I'd be more concerned about a portable electric/fuel heater, refrigerator, stove, coffee pot, toaster, "custom" wiring job, or charcoal grill before I'd worry about my Tanis heater catching fire.


JKG

 

[Cap'n Jack]

I don't want anything bad to happen to my aircraft either, but I carry adequate insurance so that such a worry doesn't keep me up at night.

JKG

Ben has a unique plane. Insurance can pay the money for the parts, but won't replace the time he will need for a rebuild. I can see where he's coming from.

 

[N801BH]

Ben has a unique plane. Insurance can pay the money for the parts, but won't replace the time he will need for a rebuild. I can see where he's coming from.

Thanks cap'n... Just to clear the air,,, I have NO axe to grind with Tannis. Or Reiff or any other product as long as that product is safe... When a handful of pilots chime in on what appears to be a "issue" I take notice... POA is just a small group of aviation enthusists and when several of them comment on failures like this I have to ask myself ' just how widespread is this'? considering the sampling size of the posters here are miniscule compared to the actual fleet operator size.

J Goodish........ I Apoligize if I offended you and Tannis...

Ben.

 

[JGoodish]

Thanks cap'n... Just to clear the air,,, I have NO axe to grind with Tannis. Or Reiff or any other product as long as that product is safe... When a handful of pilots chime in on what appears to be a "issue" I take notice... POA is just a small group of aviation enthusists and when several of them comment on failures like this I have to ask myself ' just how widespread is this'? considering the sampling size of the posters here are miniscule compared to the actual fleet operator size.

J Goodish........ I Apoligize if I offended you and Tannis...

Ben.

No apology necessary. I have no connection to Tanis other than being a customer, though as I mentioned, I would probably lean toward Reiff if I had it to do all over again. I'm not a huge fan of the CHT/intake bolt design of the Tanis heating elements.

I have seen nothing to indicate that Tanis or Reiff is unsafe. I've heard many stories of propane and various types of rigged-up engine heaters causing fires or other damage to aircraft. While Tanis and Reiff may manufacture their systems under FAA-PMA, continued airworthiness (including periodic inspection) is always the responsibility of the owner/operator.

I can understand that a self-built experimental is in many ways irreplaceable, but the reality is that aircraft are subjected to multiple risks in the aviation environment. Personally, I'm not sure how I could subject such an investment to such risks if I did not feel that it could be adequately protected with insurance.


JKG

 

[N801BH]

I can understand that a self-built experimental is in many ways irreplaceable, but the reality is that aircraft are subjected to multiple risks in the aviation environment. Personally, I'm not sure how I could subject such an investment to such risks if I did not feel that it could be adequately protected with insurance.


JKG

I do my best to reduce my risks but when someone like me creates a one of a kind prototype there is always a chance of total destruction caused by a million different 'gotcha's' . I am 400 hours into a testing phase that equates to twice around the world at the equator without any emergency off airport landing... I do my best to look at
all the things that will kill me and so far I have beat the reaper..

My beef is to have it destroyed by someone else through faulty wiring and /or homemade
rube goldburg heaters..

Ben
www.haaspowerair.com