[cleanandshine]

i have a sureflow 100psi pump that was used with a varistream. now it isnt and my only problem is the pressure switch doesnt kick in when i stop the flow. i think the pressure switch has been disconnected and i am just wondering how to reconnect the switch

http://www.williamson-shop.co.uk/contact-us-2-w.asp

Very helpfull and very good prices

[dmlservices]

i have a sureflow 100psi pump that was used with a varistream. now it isnt and my only problem is the pressure switch doesnt kick in when i stop the flow. i think the pressure switch has been disconnected and i am just wondering how to reconnect the switch

thanks stuart

if you are using a bypass , the pressure switch will not activate, as water will circulate around bypass when you stop the flow, thats one of the reasons i dont use one, as the pump would be running all the time, until it is turned off.

daz

yes i know mate it doesnt bother me that it keeps running. i only want to reconnect for the rare occasion i turn the flow up full because this stops the circulating

oh i see you would need the pressure switch to activate then 

daz

[dmlservices]

I still connect all my pumps up with a bypass in case anyone wants to turn the flow down for any reason.  I would personally use it on full power all the time as it is faster that way to clean a window. 

I would also recommend anyone not using a flow controller to fit a relay to the system.  A relay is around £2-£3 and you all know what a flow controller costs.  Even if the pump cycles the relay takes the hit rather than the pump switch.  These relays are heavy duty compared to the pressure switch, after all how many times are they stopping and starting the power going to a cars indicators in their lifetime.  And if they do need changed then 30 second and a couple of pounds and its done.


The flow controller was introduced to save on replacement pressure switches, and the relay does exactly the same.

Peter

what relays do you use?

daz

[dmlservices]

i agree totally peter and i will go say the same on the other forum. in fact we all learn all the time in this game and in one sense i should have stuck with the pump you supplied in the first place and not wasted money and time mucking about with flow controllers. but i always read about the controllers that much that you get thinking that may be way to go. but its not in my opinion  keep it simple is my way

i work with my varisream ( the old dial type) on a high flow rate mostly , for a few delicate windows i will turn it down,   
 the main reason i use it is for time when i am furthest from the van, and stop poling to- either do a few windows inside, or the customer brings out a drink , and i stop for a chat,
 i stop flow, pump stops,  with a bypass it would keep running until i go back to van to turn it off, i do like the idea of a bypass though and would consider using one when my varisream wears out , to many problems with the digital one.

daz

[Peter Fogwill]

what relays do you use?

daz

It is just a simple 12V relay from Maplins.

Peter

[Mike 108]

Mike. have a look at this page it will explain it better than I can.  http://wiki.answers.com/Q/What_is_a_relay_circuit

I know for a fact that with the relay fitted I send out no pump switches, and before I started using the relay I was sending them out on a regular basis.  When wired into the circuit the relay is stopping and starting the pump and not the pump pressure switch..  The relay has much bigger contacts in it than the pump switch, and less likely to burn out.

I get them at Maplins, and I will post the part No, and diagram when I get the chance.

Peter

Peter.

Thanks for the reply, but ...

I'm confused because (as I understand it) water pressure within the pump activates the switch to turn OFF the electric current to the pump. In other words - it's a mechanical pressure switch.

I have always assumed 'relays' to be electrical switches - so don't understand how water pressure can activate them.

I need 'enlightenment'!   

Regards,

Mike

[Peter Fogwill]

Hi Mike, sorry but I am not an auto electrician, and don't know a great deal about electrics, perhaps someone who does could step in and explain?  Until then I will have a go.

I know if you have something like a remote control for instance that is rated at say 3amp and you wanted it to turn a 7 amp pump on then you would use a relay in the circuit.  The remote control would switch the relay, and the relay would switch the pump on. 
The reason the remote would be rated at 3amps is because it can't handle a higher current than that flowing through it, hence the relay, the relay only needs a small current to open the feed between the battery and the appliance the battery is supplying, which is more than the remote can handle.

Now I would guess that with the relay in the circuit with the pump pressure switch and the pump, what is happening is the power from the pressure switch on the pump is opening and closing the direct feed from the battery to the pump motor without going through the pressure switch.  So what is happening is the pressure builds up in the pump, and the pressure switch opens the direct feed in the relay to allow the power to pass direct from the battery to the pump motor, and because it is not the 7amps that is needed to start the pump flowing through the pressure switch it greatly prolongs the pressure switch life.  The trouble with the pressure switch burning out and the fact that I said the relay takes the hit, I mean the relay is directing the power needed to run the pump straight from the battery, through the relay, and to the pump motor, and all that is happening in the relay itself is a small amp signal going from the pressure switch on the pump, to open the contacts in the relay.

The pressure switch is not burning out because it is opening and shutting all the time, it is more to do with the 7amp load that is flowing through it.  Much the same is if you had a big chunky pressure switch on the pump instead of the little flimsy one supplied.

Do you understand this, or dosn't it make sense??

Peter

[Peter Fogwill]

Peter.

Thanks for the reply, but ...

I'm confused because (as I understand it) water pressure within the pump activates the switch to turn OFF the electric current to the pump. In other words - it's a mechanical pressure switch.

I have always assumed 'relays' to be electrical switches - so don't understand how water pressure can activate them.

I need 'enlightenment'!   

Regards,

Mike

Yes and it is not the mechanical part of the switch that causes the problem but the electrical part due to the heat generated by the 7amp load.  It is a mechanical action that opens and closes electrical contacts in the switch, and when the switch goes wrong it is not because of the mechanical part, it is due to the electrical contacts sticking together with the heat.  A small electrical current going through the contacts and the life of them is greatly increased, and all it takes is a very small electrical current to open the flow on the relay, from the battery to the pump motor.

I have probably explained it better in this post than the last one.

Peter

[Mike 108]

Hi Mike.  Do you understand this, or doesn't it make sense??

Peter

Peter,

Yes, I think I am beginning to 'get it'.

Thanks for taking the time to explain in such detail.

Best wishes,

Mike