[ftp]

I am now. Let me explain, i stopped home for lunch and a coffee and when i opened the front door my van was spurting water out of the door seals everywhere 
The seal had blown on the top of my di vessel and was pumping at full belt everywhere - even the footwells were full in the cab. I reconnected several times but the same thing happened every time, the 'o' ring blew out all the time. I thought the varistream was shot but on the last attempt i could see the plastic top warping under pressure. Turns out the thread is now damaged and won't hold under pressure. I have now put the di before pump so that i'm sucking rather than blowing.

[DaveG]

hi, do you leave your pump/varistream turned on all the time?

[macmac]

How can this happen with a varistream? surely you set it to cut off approx 5 seconds after pole dissconnect?

Tony

[alanwilson]

I have said many times before that the di should be before the pump if you have it in the van - I have also said that creep stress will eventually start destroying di vessels.

No one believed me.

[ftp]

I leave it switched on most of the day. I've had this happen once before on a knackered battery when the sensor wouldn't cut under pressure - i thought the voltage was too low to trigger the sensor. The battery i have now has a colour code on the top to tell you when it needs charging - it looked ok.

[macmac]

I have said many times before that the di should be before the pump if you have it in the van - I have also said that creep stress will eventually start destroying di vessels.

No one believed me.

No creep stress, no leaks, no blown seals in 4.5 years with the same vessels. I have run these vessels from very high mains pressure on-site too!

Maybe there are di vessels & then there are di vessels?

Tony

[ftp]

Got me thinking that it only needs a hozelock connector to fail on the pressured side and the whole 650ltr will pump into the van if left unattended. 

[macmac]

My di's are fitted with brass connectors which can't blow off!

Tony

[ftp]

So are mine but the hose could blow or split  anywhere from pump to pole hose (100mtr) because i leave it switched on all day. I would much rather pressure the vessel but i can't now unless i buy another or a new top but being a tight sod i don't think i will.

[alanwilson]

creep stress can happen over a period of a few days (or less) to 100 years - the fact is that the pressure has caused a deformity to occur and the result is new fittings etc needed.

[ftp]

I must admit a week ago i would have argued that one. My pressure setting is as low as it goes and my flow is only on 2 on my digital Varistream.

[see clear lee]

ive had this too but it was only a 400ltr tank that empied into me van, its a nightmare as it takes ages to drain all the water out even with a vax ,and parking on a hill to drain the van , had water comming out of holes everywhere, im looking for a head replacement too but at £30 its flippin expensive for a bit of plastic

[Alex Wingrove]

thats why i said also the pump should pull through the DI not push, so this doesnt happen

[ClearviewServices]

Cant understand why people have there DI in there van if they make there pure water at home.
And before you say its just incase we run out on the job then all i can say is plan your day better.

[ftp]

You might have a good point there. I can't think why i have it in the van really - seemed a good idea at the time. I couldn't top up with tap water anyway because tds is so high round here.
 How can i adapt my di so that it runs on my static system?

[L.J.Thorpe]

i only have a tank on van and if i have to move more than a few yards i turn pump off and de pressurize system,first week of using the van mount the hose reel fell over in the back (my fault ::)testing diy baffles) knocked the brass hozelok off the elbow and it was 5 miles later that i discovered it
do large di vessels have to "pressure up" is that why you leave the system pressured

[davids3511]

I have said many times before that the di should be before the pump if you have it in the van - I have also said that creep stress will eventually start destroying di vessels.

No one believed me.

I used to have it that way, had nothing but trouble with air locks and intermittent flow problems.

[LWC Ltd]

I was thinking to have 2 DI vessels in the van but to use them when filling tank up.

Then water would be taken straight from tank.

Good idea or bad idea? Not too experienced with this - been using back pack till now.

BTW What is creep stress?

[alanwilson]

I have to agree with clearview - we have a di in each van but they're only there incase of emergencies. All our water is RO/DI before the holding tanks anyway.  Truth be told there is no need for us to have the di in each van but like I said its there just in case, some of our work is over an hours drive from home so its better to be safe.

davids - the problem is that everyone tends to use hozelock, they're not that good.  We use push-fit connections and tubing, they are gas tight and so we never ever get any leaks, never have to run air out of the system, its a much better system.

[Bazzy1999]

Cant agree more.... why run your ro water through a di while cleaning..
If you have a static system then just put the pure straight into your van tank and use it without the agro of air locks..
But if you have your ro and di all fitted up in your van then do the same and then you have the option to disconnect your di and top up if you need it..


Bazz...