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Andair - Vans FUEL VALVE FS 20X20-3

karu

Member
Wonder if anyone can help me with the return nipple sizes of this fuel valve. Description omits the return size. Heading says 3/8 and 1/4 while numbering (20X20-3) suggests both return and supply are 3/8. Can someone who bought or used this clarify the size?
Thanks

 
For both supply and return, you need 4 EF20's (90 elbows) and 2 MF20 fittings. Assuming you are using the TS Flightlines fuel lines.
 
For both supply and return, you need 4 EF20's (90 elbows) and 2 MF20 fittings. Assuming you are using the TS Flightlines fuel lines.
Thanks for the info. I actually am planning on using rigid aluminum lines for both return and supply. Are all the nipples in the valve 3/8"?
 
I have the same question, I am also considering using the SDS EFI system and planning on using TS Flightlines fuel lines. I just want to confirm this valve FS 20X20 3 will work with the appropriate fittings? Thanks
 
Wonder if anyone can help me with the return nipple sizes of this fuel valve. Description omits the return size. Heading says 3/8 and 1/4 while numbering (20X20-3) suggests both return and supply are 3/8. Can someone who bought or used this clarify the size?
Thanks

The feed connectors are for 3/8" [aka #6] lines. The return lines are 1/4" [aka #4] lines. Unless no room, you should avoid the use of 90 degree fittings. Your idea of using tubing is the best choice. Second choice would be 45 degree fittings .Using bent tubing greatly reduces the possibility for creating a vapor lock situation.
 
Thanks all for your valuable input. Since some of you wondered, I am building a plastic airplane (Cozy mk iv) 😀. My plan is to plumb it for SDS EFI to be added later. Right now I have everything for mechanical fuel injection.
I am hanging out here as there are so many helpful people who can give good advice on fuel / engine.
Thanks again for all the replies.
 
I bought an FS2020 direct from Andair a couple years ago. Going with SDS EM-6. They can put on whatever fittings you want, which in my case was 6x3/8”. I have reservations about a smaller return line at low/no engine RPM but maybe it’s ok 🤷‍♂️
 
The feed connectors are for 3/8" [aka #6] lines. The return lines are 1/4" [aka #4] lines. Unless no room, you should avoid the use of 90 degree fittings. Your idea of using tubing is the best choice. Second choice would be 45 degree fittings .Using bent tubing greatly reduces the possibility for creating a vapor lock situation.
Sorry, but I don’t believe this is correct. The FS2020 is 3/8 on supply and return. The FS22 is 3/8 feed and 1/4 return (has NPT fittings in the bottom) and not suitable for SDS EFI. I think the page on the vans site may not be accurate? Looks like the photo is of a FS2020 (as is the part number) but the description matches that of the FS22
 
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I actually emailed vans yesterday morning. Haven't heard back from them yet. I will try to call them before ordering.
 
I actually emailed vans yesterday morning. Haven't heard back from them yet. I will try to call them before ordering

I hope they have the right one for you. I ordered a FS2020 direct from andair on the 8th of June 2023, and finally received it on the 3rd of April 2024 - almost 10 months! You can make a baby quicker than that...
 
Wonder if anyone can help me with the return nipple sizes of this fuel valve. Description omits the return size. Heading says 3/8 and 1/4 while numbering (20X20-3) suggests both return and supply are 3/8. Can someone who bought or used this clarify the size?
Thanks

Andair makes a duplex valve with 1/4 and 3/8 returns as well as 1/4, 3/8 and 1/2 in supply. Vans pre-plums their RV14 QB wings with 3/8 supply and return lines. My guess is the Vans valve shown has 3/8 supply and 1/4 return. Be careful with ordering "stock" valves from Vans and ACS as these for the majority come with straight fittings and the 90's are fairly expensive (And avoid the banjo fittings way too much pressure drop) but well built like most Andair fuel parts. As to using a 1/4 in return line I performed multiple pressure drop experiments with a FS-2020 (AN6 supply and return) using both 1/4 and 3/8 lines as a return and found even with full by-pass the 1/4 in return lines still needed the pressure regulator in the return line. (Set to 35 psi). With the fuel pressure regulator by-passed supply pressure would not get to the required 35 psi. If ever I was to build another airplane, I would definitely consider a valve with 1/2 supply and 3/8 returns for 200 hp and higher applications.

Anyone looking for a FS2020 duplex valve from Andair SMS me. Andair is now down to more reasonable supply times for these valves. (Currently less than 4 months)
 
Andair makes a duplex valve with 1/4 and 3/8 returns as well as 1/4, 3/8 and 1/2 in supply. Vans pre-plums their RV14 QB wings with 3/8 supply and return lines. My guess is the Vans valve shown has 3/8 supply and 1/4 return. Be careful with ordering "stock" valves from Vans and ACS as these for the majority come with straight fittings and the 90's are fairly expensive (And avoid the banjo fittings way too much pressure drop) but well built like most Andair fuel parts. As to using a 1/4 in return line I performed multiple pressure drop experiments with a FS-2020 (AN6 supply and return) using both 1/4 and 3/8 lines as a return and found even with full by-pass the 1/4 in return lines still needed the pressure regulator in the return line. (Set to 35 psi). With the fuel pressure regulator by-passed supply pressure would not get to the required 35 psi. If ever I was to build another airplane, I would definitely consider a valve with 1/2 supply and 3/8 returns for 200 hp and higher applications.

Anyone looking for a FS2020 duplex valve from Andair SMS me. Andair is now down to more reasonable supply times for these valves. (Currently less than 4 months)
Use 3/8 -6 for both Supply and Returns. All of our packages are set up that way. That sizeing was based on what Ross at SDS suggestedd. Made life easy for us to design the tubes on the 14.

Tom
 
Andair makes a duplex valve with 1/4 and 3/8 returns as well as 1/4, 3/8 and 1/2 in supply. Vans pre-plums their RV14 QB wings with 3/8 supply and return lines. My guess is the Vans valve shown has 3/8 supply and 1/4 return. Be careful with ordering "stock" valves from Vans and ACS as these for the majority come with straight fittings and the 90's are fairly expensive (And avoid the banjo fittings way too much pressure drop) but well built like most Andair fuel parts. As to using a 1/4 in return line I performed multiple pressure drop experiments with a FS-2020 (AN6 supply and return) using both 1/4 and 3/8 lines as a return and found even with full by-pass the 1/4 in return lines still needed the pressure regulator in the return line. (Set to 35 psi). With the fuel pressure regulator by-passed supply pressure would not get to the required 35 psi. If ever I was to build another airplane, I would definitely consider a valve with 1/2 supply and 3/8 returns for 200 hp and higher applications.

Anyone looking for a FS2020 duplex valve from Andair SMS me. Andair is now down to more reasonable supply times for these valves. (Currently less than 4 months)

This is what Andair documents for their FS2520 fuel valve. For applications with engines over 200 hp worth considering. Vapor pressure issues at altitude with ethanol enriched fuels is a real issue.

"The FS2520 has a 1/2" feed section and a 3/8" return section. A variant of the FS2520 valve is used to supply engines such as the Continental IO-550-N and is used in the acclaimed Cirrus SR22."
 
Thanks both of you for the info. With a 180 hp engine, I definitely need 3/8" all around for the peace of mind.
 
Did anyone get a response from Vans about which one they are selling? Their store has a nonexistent or incorrect Andair model number and a description that doesn't match the valve pictured. I asked a question on their store entry.
 
Sim, todos eles têm 3/8.

Acabei de instalar isso no meu -14.

Possui um padrão de parafusos e um método de montagem diferente da válvula normal. Veja como resolve isso (anel de porca).
Did you buy the valve directly from the Vans website? Can you confirm that the return is 3/8"? I'm thinking of buying one to install SDS EFI + TS Flightlines. Thank you.
 
Did you buy the valve directly from the Vans website? Can you confirm that the return is 3/8"? I'm thinking of buying one to install SDS EFI + TS Flightlines. Thank you.
Got it direct from Andair. Took ages for them to make it - months!!

Yes it’s 3/8 supply and return.
 
Did you buy the valve directly from the Vans website? Can you confirm that the return is 3/8"? I'm thinking of buying one to install SDS EFI + TS Flightlines. Thank you.
I would double check with Vans. Their pricing is 1/3 that of ACS and considerably less than Andair for a duplex valve. In fact, it's cheaper than the Andair supply only no return valve that Vans sells. Something is amiss. Andair has been able to decrease their lead times on the duplex valve to 6 to 8 weeks. Last item I ordered from them Fed Ex was still charging duty so factor that in and good luck.
 
I would double check with Vans. Their pricing is 1/3 that of ACS and considerably less than Andair for a duplex valve. In fact, it's cheaper than the Andair supply only no return valve that Vans sells. Something is amiss. Andair has been able to decrease their lead times on the duplex valve to 6 to 8 weeks. Last item I ordered from them Fed Ex was still charging duty so factor that in and good luck.
Mine took 10 months so that is a great improvement! Back when I paid for it, in March 2024 it was £460 (with shipping).
 
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