Pump position help..

[Jonny 67]

?

 

[Deleted member 7446]

 

[Stevieboy]

My son has a 500litre tank in his van and the pump is above the top of the tank. Shurflo pumps specs indicate a 12' head meaning that the pump will prime 12' above the level of the water. If there is air getting into the system, its being sucked in on the inlet side of the pump starting from the tank outlet.

As @Apw1210says, all hose connections need to be tight and seal completely.

Are you sure.???? Head means how high a pump will push water out of its discharge side vertically. Lille a fountain. Didn’t know it had anything to do with suction???

 

[Pjj]

Are you sure.???? Head means how high a pump will push water out of its discharge side vertically. Lille a fountain. Didn’t know it had anything to do with suction???

Yes I think you are right , water being drawn below the pump height is called water lift .

 

[spruce]

Are you sure.???? Head means how high a pump will push water out of its discharge side vertically. Lille a fountain. Didn’t know it had anything to do with suction???

Thanks. I stand corrected. If our pumps had a 12' head then they would be useless.

Shurflo pump specs.pdf

 

[Jonny 67]

Oh no. I've just fitted the pump on the van roof! ?

 

[Stevieboy]

Thanks. I stand corrected. If our pumps had a 12' head then they would be useless.

Shurflo pump specs.pdf 573.81 kB · 3 downloads

It’s good to know the specs though. Being self priming up to 12’ kind of means you can’t really mount you pump to high in your van. Mine is mounted roughly have way up the van side and I’ve never had an airlock issue. 

 

[Deleted member 7446]

Oh no. I've just fitted the pump on the van roof! ?

You probably cable tied it to the roof rack ?

 

[Jonny 67]

Half way it is?.

 

[Jamesmarshall]

I have always put my pumps high on the wall this explains my air lock problem ?

Also my pumps are upside down to most pictures on here , does this make any difference ?

 

[Jonny 67]

I think it would make a difference if you had a leak, as the water can run inside the pump (I think)...

 

[Deleted member 7446]

I have always put my pumps high on the wall this explains my air lock problem ?

Also my pumps are upside down to most pictures on here , does this make any difference ?

The way I see it with regards to your question about pump orientation is having the input output on the bottom ensures that the diaphragm chamber is always flooded and water cavitation has less of a chance

 

[Jonny 67]

As long as you position the pump at the lowest level possible you will minimise getting air locks. I’ve also got a tank valve from eBay

203279050147

if I’m really low on water and driving a distance I shut the valve and reopen when I get there to stop the air getting in the system 

Would I be correct in thinking, that if I put this valve between the pump and my di vessel (I double di in the van for convenience) and turned it off when I'm changing my resin, then I'd stop air getting into the system?

 

[Jonny 67]

Would I be correct in thinking, that if I put this valve between the pump and my di vessel (I double di in the van for convenience) and turned it off when I'm changing my resin, then I'd stop air getting into the system?

Actually, I think a 15mm non return valve will do the job. I'll check it out this week ?

 

[Deleted member 7446]

Would I be correct in thinking, that if I put this valve between the pump and my di vessel (I double di in the van for convenience) and turned it off when I'm changing my resin, then I'd stop air getting into the system?

You can get inline male to male barbed NTR's which you can as mentioned add inline between your DI and pump, also I have one after the pump and before the hosereel.

These are what I am currently using

 

[Pjj]

You can get inline male to male barbed NTR's which you can as mentioned add inline between your DI and pump, also I have one after the pump and before the hosereel.

These are what I am currently using

View attachment 25112

Maybe a stupid question but why do you use them ?? I have only ever had issues with an air lock when I first installed the system into the van . 

 

[Jonny 67]

Maybe a stupid question but why do you use them ?? I have only ever had issues with an air lock when I first installed the system into the van . 

I'd need it to stop air getting to the pump when I'm changing resin ?

You can get inline male to male barbed NTR's which you can as mentioned add inline between your DI and pump, also I have one after the pump and before the hosereel.

These are what I am currently using

View attachment 25112

Thanks again APW 

 

[Pjj]

I'd need it to stop air getting to the pump when I'm changing resin ?

Thanks again APW 

How often are you changing resin ?? If the pump is low to the tank it should self bleed when turned on all mine do 

 

[Jonny 67]

How often are you changing resin ?? If the pump is low to the tank it should self bleed when turned on all mine do 

I'm changing resin every 2 weeks, and always get air into the system when I change. I'm obviously doing something wrong. My thinking now is that if I can shut off the water between pumps and resin, then air won't get into the pumps. They never self bleed, and are about a foot from the van floor. 

 

[Pjj]

I'm changing resin every 2 weeks, and always get air into the system when I change. I'm obviously doing something wrong. My thinking now is that if I can shut off the water between pumps and resin, then air won't get into the pumps. They never self bleed, and are about a foot from the van floor. 

Dear me that’s a lot of resin Ime assuming you are di only ?? My pumps are about the same height as yours , sounds strange why you are having problems?? Don’t know what to suggest, I have never liked non return valves as it puts more strain on the pump all the time having to hold them open , but maybe it’s worth a try . 

 

[Jonny 67]

Dear me that’s a lot of resin Ime assuming you are di only ?? My pumps are about the same height as yours , sounds strange why you are having problems?? Don’t know what to suggest, I have never liked non return valves as it puts more strain on the pump all the time having to hold them open , but maybe it’s worth a try . 

Sorry, I didn't make it clear. I'm di only. Using about £7 worth of resin a week. For me that is cost effective, as I don't have the hassle of ro units, though I will probably look into that when I've more time. Tap tds of 70ish.