R

ron sterba

Well Known Member
Went to do my first taxi test. (XIO-320 Lycoming). Andair boost pump came to life,first by fast clicking sound for 3-4 seconds then slow clicking for 2 seconds and the 5 amp fuse blew. 5 amp is what instructions called for. New fuse put in, this time disconnected hot lead to pump relay, loaded, wiggled wires,switch on and off. Hooked hot lead to relay, same sequence of noises then 5 amp fuse blew. I so I thought that the relay function to stop pumping after back pressure build up might be the problem. So figuring i hear the the pump ramp up fast clicks that I would turn off the switch to the Andair boost pump. I used this technique 3 times. Turned the starter on and the new lycoming engine and came to life. A lot quieter because of the Vetterman mufflers. ( iam not a Harley guy). I put only 2.5 US gallons of 100LL in each tank. Ok idle adjusted to 800 rpms +|_ 35 rpms as shown on the Dynon display. Shut it down after 4 minutes. Switched tank selector to see if I could (left tank) fuel pumped through empty line on left tank. Did same sequence of just 3 seconds bursts of boost pump switch for 4 times. Tried start up after 5 seconds the engine started, never missed a beat for 4 minutes of taxi time no leaks.

I emailed Mr PHILLIPS at Andair over the weekend so some time this week I expect to hear. Didn't notice any problem around Andair pump. I didn't see and expected noises from reading instructions other than expecting a pump to make noise if it runs. I just don't know what rythem I should be hearing as a NEW ANDAIR pump during activation of on/off switch. The Dynon display with the red cube showed a fuel burn of 1.7 gal per hour on idle, forgot number on fuel pressure but it was in the green.

I noticed Aircraft Spruce is out of stock at both locations in US. Whether it's a popular item or Andair isn't supplying them anymore. With UK opting out, maybe a financial period looms. Don't know. My inspector says get it fixed by the tenth of July,after that he leaves for Oshkosh summer vacation. My option is drive 20 minutes up to Vans for their in stock fuel pump ( different brand).

Your thoughts, remedy , or go to Vans, or use a larger fuse?

Ron in Oregon.
My successful start up was due to all of you who over the past 6 years have offered your thoughts and pictures and most of all to Vansaiforce's founder and family and all the guardians of this website. I SAY THANKYOU,
 
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I'm pretty sure I had to go to a 7.5 amp. fuse on mine. Haven't flown yet but have run the engine.
 
Ron B. said:
I'm pretty sure I had to go to a 7.5 amp. fuse on mine. Haven't flown yet but have run the engine.
Click to expand...

Yep - 7.5A breaker for the vans pump.

I note the spec sheet for the Andair PX375 says 6 amps max, 4.5 nominal.

Hopefully, your wire size is adequate for a larger breaker/fuse.
 
Hi Ron,

I have no direct experience with the Andair pump, but a couple of general thoughts.

Assuming it's the PX375, the spec sheet says '6 amps max' (note that it *doesn't* say '6 amp fuse'). That means that it can draw up to 6 amps (and likely will, in some situations). What the spec sheet doesn't say is that it's fairly likely it will have very short duration surge currents (typically during startup loading) higher than that.

The circuit drawing shows a 6 amp *circuit breaker*, not a fuse. Typical circuit breakers have a much longer time constant than typical automotive fuses. The automotive fuse is 'fast blow' and will blow, well, fast. It takes very little overload and a very short duration to blow it. A circuit breaker will have a much longer time constant (think 'slow blow') and will tolerate short term 'surge' currents significantly higher than its amp rating. So... if you replace your fuse with a 6A circuit breaker, you may find that everything works ok.

As a FWIW, the Andair document is inconsistent with good electrical practice. Good practice is to protect at around 20-25% above the maximum demand of the device, to avoid nuisance trips. So, if the pump really can draw '6 amps max' (and not just transient surges) in any normal mode of operation, then Andair has set up its users for nuisance trips.

Charlie
 
Andair Fuel Pump

Hi Ron,
I had the same issue with my Andair pump when first activated in my 9A. If it's an early build, I believe mine is serial number 15, I read somewhere that the manufacturers didn't anticipate them sitting on a shelf for several years and didn't put a preservative lubricant in them. I solved my issue by capping off one end, filling it with av-gas, then capping the other, then leaving overnight. After draining the fuel and testing, the pump worked flawlessly. I can't recall the amperage on the VPX, but I think I've got a 10 amp breaker for the backup CB.
 
Charlie great food for thought, I'll try the 6 amp circuit breaker. I didn't know that about the fuses blowing quicker.

Ron in Oregon.
 
Ron,

What size wire are you using to power the pump? Generally, we choose the wire size based on the requirements of the load (pump). Then we choose the value of the fuse/breaker to protect the wire.

Also, I believe fuses trip faster than breakers so there may be a consideration there too.

It would seem to me your fuse is significantly undervalued.

Bevan
 
Hi Michael, I like your thought for back up and a circuit breaker. Now Bill mentioned about the wire gauge, I'll have to check my list of AWG WIRES IN each CIRCUIT. IM GLAD I marked down all AWG wires for each circuit ( thanks to Joe Dubner EAA292). I tried to go heavy on gauges rather than adaquet for the unit usage. I'll check tomorrow my AWG list as tonight we are celebrating the 4 th of July.

Thanks

Ron in Oregon
 
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Hi Bevan, good point, I think I'll leave the 4th party and head to the airport. Be back in 30 minutes.

Ron in Oregon
 
Ok one hour 3 minutes iam back. I checked and have 4feet of 16 gauge wire. FAA 43:13 book says 6amps continuous at 16 gauge would be max length 17 feet. Intermittent usage of AWG 16 @ 6 amps is 30 feet. Andair General Specification says 11-16.6 VDC 6 max amps/ 4.5 AMPS NORMAL NOW IN THE Andair Operational Manual it states to use a 5 AMP ,,,,,BREAKER,,,,,,,.. SO MY FUSE IS OUT! I learned something-here from you guys and that's a good thing!!!!! Now In the GENERAL OPERATION - Pump ( info sheet from Andair) "Once power is applied the pump will initially pump at 100% power then settle back to 75% power after 2 seconds. This is so that pressure in the line is built up quickly". As I explained earlier of my experience in pump noise sequences this would be right on the 100% and 75% cycles. I'm a little gray in the area of how long to I apply the boost pump switch, do I look at the fuel pressure gauge on the Dynon EFIS ? ( what should I be looking for in the fuel pressure reading, climbing, steady,??). At what point should consider switching off boost pump and then attempting to start my XIO-320?

My next question would be,,,,,,,,,,, if I'm flying and want to which tanks,,,how long before I move the selector knob to I turn on the boost pump, and how long after the selector to the new tank should I continue operating the pump? I know the engine has a engine driven pump. But can you explain how you do the switchover.

Thanks Ron in Oregon

Ron in Oregon
 
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Charlie you say 6amp circuit breaker, my spec sheet shows 5 amp breaker. Maybe Andair changed the operating circuit breaker value. I'm thinking a search here might reveal somethingfromthe past,somethingishould have checked first. Thanks Charlie
 
My Andair pump went Tango Uniform in the first 5 hours also.

Maybe this should be another poll thread like the alternator thread?

Anyways, what Andair told me was that the vanes need to be fitted properly in order to determine how much current this little bugger will draw. The more friction and closer tolerance on the vanes, the more current it will pull in order to spin the motor.

So, I have the VPX system and can see the actual current draw. In normal operation it is 4.5 amperes. When I was having the problem, I got an alert in the vicinity of 14 amperes. That tripped out the circuit on the VPX and I landed uneventfully on my mechanical pump. When I removed it from the plane and retested it on the bench, I saw a short circuit according to the VPX (which I used to power the unit while it was on the bench so I could monitor the current and switch it on and off effectively). Current was over 20 amperes on subsequent tests and the rotor did not spin.

Andair took it back, gave it some TLC and it has now been working fine for 1.5 years and 420 hours (yes, you read that correctly... 420 hours in a year and a half)!

With regard to your fuse size... 5 or 6 amperes is fine. If you pull over that you have a problem and need to send it back. The surge current on start should not blow a 5 ampere fuse. It is an AC brushless motor and in my observations it really doesn't spike the current on start.

When mine went back to merry old England I was fortunate to borrow a pump from another fellow builder and fly on until it was returned. It did take about one month for post and bench time.

Sorry for the bad news. You must send it back to be repaired.

You will be glad when it comes back. It is a good little pump and the filter is very effective! In operation I see 29-32 PSI and current is always stable at 4.5 amperes.

Good luck!

:cool: CJ
 
ron sterba said:
Ok one hour 3 minutes iam back. I checked and have 4feet of 16 gauge wire. FAA 43:13 book says 6amps continuous at 16 gauge would be max length 17 feet. Intermittent usage of AWG 16 @ 6 amps is 30 feet. Andair General Specification says 11-16.6 VDC 6 max amps/ 4.5 AMPS NORMAL NOW IN THE Andair Operational Manual it states to use a 5 AMP ,,,,,BREAKER,,,,,,,.. SO MY FUSE IS OUT! I learned something-here from you guys and that's a good thing!!!!! Now In the GENERAL OPERATION - Pump ( info sheet from Andair) "Once power is applied the pump will initially pump at 100% power then settle back to 75% power after 2 seconds. This is so that pressure in the line is built up quickly". As I explained earlier of my experience in pump noise sequences this would be right on the 100% and 75% cycles. I'm a little gray in the area of how long to I apply the boost pump switch, do I look at the fuel pressure gauge on the Dynon EFIS ? ( what should I be looking for in the fuel pressure reading, climbing, steady,??). At what point should consider switching off boost pump and then attempting to start my XIO-320?

My next question would be,,,,,,,,,,, if I'm flying and want to which tanks,,,how long before I move the selector knob to I turn on the boost pump, and how long after the selector to the new tank should I continue operating the pump? I know the engine has a engine driven pump. But can you explain how you do the switchover.

Thanks Ron in Oregon

Ron in Oregon
Click to expand...

Your wire size and length is fine. Try the 5 ampere FUSE for now. I bet that you would be fine there as well.

Run your engine like it is a Piper Arrow.

Cold start = Full power and full mixture and hit the boost pump for 3 seconds to develop 18 or so PSI on the system. Pull power to idle and crank the engine. It will start up just fine.

Lycoming says that the boost pump must be operated while switching tanks and Piper has put that into their manuals as well.

In practice... meh :p

The engine needs an uninterrupted fuel supply and the mechanical one does just fine. Me??? I follow the Lycoming instructions and turn the boost pump on, watch for a climb in pressure, switch tanks and then shut boost pump off.

Have fun in Phase 1!!! It is what you have worked so hard for! Enjoy the testing!

;) CJ
 
ron sterba said:
Charlie you say 6amp circuit breaker, my spec sheet shows 5 amp breaker. Maybe Andair changed the operating circuit breaker value. I'm thinking a search here might reveal somethingfromthe past,somethingishould have checked first. Thanks Charlie
Click to expand...

I just googled it; I think this was the page I looked at; found through a/c spruce:
http://www.aircraftspruce.com/catalog/pdf/PX375-TC.pdf

An interesting data point: The 28 Volt version's data sheet, from Andair's web page:
http://www.andair.co.uk/wp-content/plugins/wizbit-ecommerce/assets/media/PX375-TC-28V.pdf

Note that the current demand is only 3 amps (reasonable, given the higher supply voltage), but the recommended CB size is still 6 amps.

Lots of seeming inconsistencies in their docs.

Edit (was in a hurry this morning): The 28V product's circuit protection vs. demand is a lot more 'sensible' than the 14V product. Panel mounted circuit protection should be there to protect *the circuit* (the wires); not the device. A lot of mfgrs have started to spec circuit protection values to protect their device, instead of building the device protection *into* the device (much cheaper for them, and provides deniability if there's a failure). But.... Does anyone really want the potential for a nuisance trip on a flight critical component like the boost pump? Consider how you'd have felt if your 1st discovery of an issue was when the mech pump had just failed & the fuse (or breaker) popped when you hit the boost pump switch.

Charlie
 
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Good points Charlie,
The good news is that Mr Owen Phillips ( President ) asked me to send it back. So today I sent it FEDEX to England. I saw the plane lift off here this afternoon for Portland Oregon, then to Memphis Tennessee processing center,then to England. To be delivered Thursday by 4:30 their time. I asked Owen if he could give me a time frame for the return. I appreciated his acknowledgement.

Question, Circuit breaker, If I install a circuit breaker on the left side of my panel just above my boost switch,( I have a hole there for one ) ,then I have 4 feet of 16AWG wire back to my fuse block on the right side of my panel,and my thinking this 4 feet of 16 AWG becomes a fuseable link. Since the 16 AWG wire is still hooked up on the fuse block pos 15, can I put in a 10 amp fuse at the fuse block and still use the the 6 amp circuit breaker at the switch??

Thanks Ron in Oregon
RV9A XIO 320
 
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Does it sound like this?

Hi Ron

Your "clicking sound" is something that I had too! Does it sould like this:
https://vimeo.com/160658922
It start with high RPM then slow down (it is programmed that way) but then is should run continously, but it does not and interrupt. This only when the line is closed, engine not running or engine in idle.

The pump is one of the first production batches, lay much to long on the shelf. Needed to replace it for first flight, send mine to Andair for a refurbishing/warranty/update to the latest status.

No result yet, it is on the way back to me. Still flying with my buddy's pump.
 
ron sterba said:
Good points Charlie,
The good news is that Mr Owen Phillips ( Pesident ) asked me to send it back. So today I sent it FEDEX to England. I saw the plane lift off here this afternoon for Portland Oregon, then to Memphis Tennessee processing center,then to England. To be delivered Thursday by 4:30 their time. I asked Owen if he could give me a time frame for the return. I appreciated his acknowledgement.

Question, Circuit breaker, If I install a circuit breaker on the left side of my panel just above my boost switch,( I have a hole there for one ) ,then I have 4 feet of 16AWG wire back to my fuse block on the right side of my panel,and my thinking this 4 feet of 16 AWG becomes a fuseable link. Since the 16 AWG wire is still hooked up on the fuse block pos 15, can I put in a 10 amp fuse at the fuse block and still use the the 6 amp circuit breaker at the switch??

Thanks Ron in Oregon
RV9A XIO 320
Click to expand...

The only way that the 16awg wire would become a fuseable link is if there were no protection at the source. Amp ratings for wire are almost always given 1st for voltage drop (resistance), and then for insulation integrity. There are charts showing different amp capacities for the same conductor, depending on which insulation is used (and I'm talking about certified aircraft wire), and whether the wire is in a bundle or free air. 16awg can carry *much* more current than the charts suggest, before becoming a 'fuse' (melting the copper). There are charts (google it) showing that 16awg can be run up to 20 feet with a 10 amp continuous load at a 10% voltage drop. This is nowhere near the capacity of the wire before even insulation failure; it's just the limit for practical resistance losses in the circuit.

Why not just use the 10 amp fuse at the fuse panel, and call it done? The pump has an internal bypass to limit pressure, and based on the descriptions given here and the video just posted, it as some internal 'intelligence' that governs its speed based on pressure and demand. So, if the pump has a fault that would blow a 10 amp fuse, what good can come from resetting a CB repeatedly? Size the wire to handle max no-fault load, fuse to protect the wire, and done.

If it will help you get more comfortable with the idea, note that since there are electronics *in* the pump, there are failure modes that can let the smoke out *without tripping Andair's recommended protection*. It's just something we live with every day, in most, if not all electronic devices, even in airplanes. Let me rephrase that; things can burn inside the device; if Andair did their job right, you probably wouldn't actually see the smoke until you opened the pump. Anyway, the point is, that's why you hear the phrase, "The fuse protects the wire; not the device."

Charlie
 
Thanks Charlie, I learned a lot in your letter. Makes sense. I'm just rounding my edges here as a novice and found myself " don't do this and don't do that" ohh can't go over what the manufacturer says. Well My friend said lets hook up a meter in in amps and check the load that is being carried. Actually pretty easy. Knowledge, from reading your post and applying I better understand the bridge carrying capacity of wire out of the bundle. Did read about bundled wires but I think that would be maybe like a airliner with LONG runs of wire. Sorta like a workout gym with partcipants and having no fans to chill the heat and sweat generated. Thanks Charlie!

Now what I have learned is, Don't buy by your electric fuel boost pump unless you plan to use it in the next 6-9 months, or follow manufacturers recommendation for storage. I think that's safe to say. My engine is new from lycoming and it came with long time storage Several years back. Price went up $7500 since then. Now avionics well that's a different story. Changing all the time, I think the manufacturers got the hardware standardized. I bought a Dynon " low powered transponder just before the 2020 mandate, yep bought the new one and sold the other to a very happy builder who knew what he was getting.

Now on the Andair pump, sending it back to the factory was $117. It should be there as we speak. That's what FEDEX said, we'll see. I'll keep you all updated on the progress.

Ron in Oreon. RV 9A
 
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Well I got the email from Jenny at ANDAIR, YES THEY RECIEVED THE PUMP YESTERDAY, and it was just two days for delivery. ( Oregon to England) ( HATS OFF TO FEDEX,,,great bunch of pilots.) Jenny said it was being tested. Wow so glad to see service being done on it. So this Friday afternoon not sure how's it's going to get to Oregon. I suggested just send it from Oshkosh to Oregon. ( Andair is suppose to be at Oshkosh) Well I have no way of getting to Oshkosh this year, so I'll let you know what's next. I'm looking at great service from Andair.

Ron in Oregon RV9A. XIO-320 D1A
 
I recieved a email from Andair about my fuel pump. It was my "O" ring that caused the problem. The motor worked fine but the failed "O" ring wouldn't allow the pump to prime. I sent a email back asking if the "O" ring is something that needs replacing every condition inspection or so many hours of use,or be sent back to the factory when it fails.

I think I may buy their gascolators for root side my wing tanks.Anyone install them on a 9A? I wasn't so keen on disconnecting my fuel filter in the cockpit. Yes I had cloth down for the drips but still bothered me.

I thought Andairs response was timely, looking forward to receiving back the pump for my airworthiness inspection.

Ron in Oregon
 
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Well good news,my pump is on its way back from England. Only 9 days since I sent it and Great Andair service! It's has a new "O" ring and will have to use a 7.5 amp circuit breaker. Andair said I should never have to go to the factory for the "O" ring replacement. As you mention in the threads about protecting the feed wire, yes 16AWG is feeding the pump and is about 8 feet long.
Cheers
Ron in Oregon RV9A
 
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Swisseagle, clicking is different than mine. Now my pump is now back in Oregon. Left Andair Thursday 2:30pm, in Memphis Tenn at mignight Friday, 5:15 am Saturday in Oregon, office closed here in Oregon ,I'll have to wait til Monday to pick it up. Tell you then.

Ron in Oregon
 
ANDAIR WAS SPOT ON Returning my pump after servicing it, Ok 11 days from Oregon to England,service., England back to Oregon, Nice going ANDAIR and FEDEX!!!!.. Picked up pump at our airport FEDEX office late this afternoon. Question, did I run the ANDAIR pump,,,,NO. Will I tomorrow YES. After I get under the panel to get wires installed and NEW 7.5 amp circuit breaker. Jumper wires made. Before I installed the pump I Installed plate nuts in place of the four AN 3 bolts that had NYLOK nuts that previously held the pump in place. Now it will be easier to remove pump if I ever need be the case. Seems we all modify the plane as we build ( DO OVER BECAUSE ITS BETTER ). Wires hooked up to pump relay and Adel clamps, EZ lube on fuel fittings two threads back from taper,snug then one flat of the "D" nut to tighten. Andair will be at OSHKOSH. You can see the different products they sell to USA vendors that includes Vans aircraft company. Personally I like robust products and I like ANDAIR products. I also have their fuel selector valve.

Here's a question I'm sure everybody has at least ONE IDEA that they would do differently to their build project. For me I like the center console with the throttle and mixture lever. This way I could have put my rocker switches on the upper part on this console as it meets my instrument pane. So what would you do differently???

Ron in Oregon RV9A
 
Swisseagle, I activated the Andair pump today and It worked and sounded as discribed in your video. Owen explained that the pump comes on at one speed for a few seconds and slower there after and it sounded as it pumped fuel until it couldn't pump anymore just like in the production aircraft I few. Pump diffinently sounded firm and in control this time. Owens thanks for covering the problem with the warranty. Hats off to Andair. My tech conselor called today asking if he could pick up my pump from at Andair at Oshkosh,I said already got it back and installed it in the plane. WHOA!

Ron in Oregon RV9A
 
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