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Do I need a relay...

T

Twodose

Active member
Switched from low pressure wax to high pressure, do I need a relay to make the HP wax run with cold water instead of hot?
 
I've done that with a relay.

wd9z.jpg
 
So we are trying to do the same thing. We have a 2 stack rotary switch and I think it would be possible to do with a 3 stack and no relay. We tried a relay but it I only had 1 output on my relay because that's all the local electric shop had, so it was back feeding into the wax solenoid and activating it for rinse as well.

So we must need a dual output relay or the 3 stack switch. Does that make sense? I'm still figuring it al out, it's confusing at first.

Thanks
 
Using this relay wouldn’t work because the rinse water comes in at about 40 psi so it won’t create suction to pull product out of the tank, it was actually pushing water backwards into the wax tank when wax was selected out in the bay.

It worked as described in the way that when on rinse it will just open the rinse solenoid and when on wax it will open the wax solenoid and the rinse solenoid at the same time.

I think the only way to get it to work is to have a separate cold water holding tank for only the wax and opening a solenoid to that tank with this relay when the wax is selected.

You may want to try these from mouser.com > 653-G7L-1A-TJ-AC24
 
Twodose said:
Using this relay wouldn’t work because the rinse water comes in at about 40 psi so it won’t create suction to pull product out of the tank, it was actually pushing water backwards into the wax tank when wax was selected out in the bay.

It worked as described in the way that when on rinse it will just open the rinse solenoid and when on wax it will open the wax solenoid and the rinse solenoid at the same time.

I think the only way to get it to work is to have a separate cold water holding tank for only the wax and opening a solenoid to that tank with this relay when the wax is selected.

You may want to try these from mouser.com > 653-G7L-1A-TJ-AC24
Click to expand...

Whenever you direct fed the pump with city water pressure you need to lower the water pressure to get the pump to draw in whatever chemical you’re trying to draw. My pumps are set up with direct feed from the city water, no gravity fed tanks. I use a Generant regulator to lower the incoming water pressure on both the Hot and Cold water and a DEMA 203C injector to draw the chemical into flow of water. The nice part of this system is there are no gravity tanks, no troublesome float valves and the pumps will last longer because they aren’t trying to draw a suction. I’ve never had a washed out pump head.
 
Randy is a wealth of knowledge and I would listen to what he says if it applies to your situation. What he is saying will work and if you ask him he will pm you to explain how to do it, in my situation I have a gravity fed tank for the hot water and since I’m on a well system the hot water is gravity fed and the cold rinse water is set at about 40-50 psi. I’m curious to know what pressure u have to reduce the city water to so you can get suction at the pump, do u use one regulator for all the incoming pressure or do you have to use a generant regulator for each pump? My rinse is coming in on a 1 inch line to all 3 pumps. 20 year old D/H equipment.
 
The other nice thing about this type of system is that you don't have a tank full of cold water. The customer gets hot water faster when using wash cycle. Also you don't lose heat as hot water dumps into the tank. It just seems like a more efficient setup. . I hope to convert to Randy's type of system eventually.
 
So you have hot water fed from a gravity tank that mixes with soap and wax, and rinse is fed via city pressure? Relays won't help anything here. You would need two tanks (one for hot and one for cold) and a control valve, or something to regulate the hot and cold pressure to the pump with pressure feed from both hot and cold (more solenoids), or maybe a separate tank just for wax diluted for straight draw (No wiring changed needed).

Look again at the relay diagram I posted. It's for a single-pole double-throw relay, so when rinse is selected it just feeds through the normally-closed circuit, and when wax is selected it switches the circuit to power the rinse solenoid from the wax input, keeping the two separated.
 
Mep001, I'm confused now as to who is giving advice to who. My system is not this way. (If you are talking to me that is)

Mine has a suction tank, but not gravity fed and it has both hot and cold water solenoids that feed the tank. I have no city water pressure on the suction side on any cycle. Then I have a soap solenoid on the suction side downstream of the tank so soap is sucked via a metering valve. I also set up a wax solenoid next to the soap input. It works as it should in wax cycle. But then the wax solenoid stays activated in rinse because I have wired it up wrong. I think it is active in all high pressure cycles. And I think this is because my relay was back feeding power into the wax solenoid either because I have the wrong relay or just wired up wrong.
 
Check the other thread you started. I posted a fix for your problem that can be addressed using your double stack rotary...No relays needed...The PDF I posted has a wiring diagram that will help you understand how it all works.

I think your getting confused as to what a gravity feed tank is...Its what you call a suction feed tank...Water is supplied to the pump via gravity feed/suction feed from the tank...Most gravity feed tanks are filled using a float valve like a Walters float valve. I have seperate hot and cold tanks that supply the pump via a 2 way Erie valve.I'll attach a few pictures to give you an Idea on how I modified my old system with new...I heat Wax and Soap with hot water. You could easily do the same thing or make it to where wax is applied with cold water.

Normally open on the Erie valve is hot...When switched to rinse, the valve picks up 24v form the rinse selection on the rotary and switches to cold...My old setup v/s new!

OLD_1.jpg


NEW_1.jpg


NEW_3.jpg
 
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I just reread your post. How does it work where you only have one grvity feed tank being supplied with hot and cold water via solenoids? Is it an Erie 2 way that feeds the tank? I guess you need to be more specific on how your system works...Either way, I still think you can do what you want using your rotary as long as its wired correctly.

I'm going to throw this at you too....IF your using an electro switch https://www.kleen-ritecorp.com/p-1728-rotary-switches-8-position-2-stack-metal.aspx Three of the positions are "Make Before Break" contacts...Meaning, when switched, the contacts make before breaking the previous contact. You want soap, wax and rinse on these contacts so the HP pump never shuts off when switching between these three selections. Lots Lots easier on the pump motor...

Is your head spinning yet?!?!?!?
 
area123 said:
Mep001, I'm confused now as to who is giving advice to who. My system is not this way. (If you are talking to me that is)

Mine has a suction tank, but not gravity fed and it has both hot and cold water solenoids that feed the tank. I have no city water pressure on the suction side on any cycle. Then I have a soap solenoid on the suction side downstream of the tank so soap is sucked via a metering valve. I also set up a wax solenoid next to the soap input. It works as it should in wax cycle. But then the wax solenoid stays activated in rinse because I have wired it up wrong. I think it is active in all high pressure cycles. And I think this is because my relay was back feeding power into the wax solenoid either because I have the wrong relay or just wired up wrong.
Click to expand...

You said you used a 1-pole relay, I think that's why why it didn't work. You must use a double-throw relay like in my diagram.

Sounds like you have Futura equipment, which usually has a separate float tank for each pump fed by both hot and cold water controlled by a single Dole solenoid valve.
 
Is Futura the brand name? What we have is just 2 solenoids (look like washing machine solenoids) and one is hot and one is cold. They both just dump independently through the float valve depending on which solenoid is active. (wash or rinse).

Someone suggested a dole type setup, which would work for wax and rinse since there would be separate circuits then for the wax and rinse water. But I still think a 3 stack switch might be cheaper and easier.

I think a single pole double throw relay might also work as MEP originally suggested. I'll check prices and see. I do like the simplicity of just putting in a 3 stack with no relays or extra solenoids to go bad. And they are fairly cheap ($25 each switch).
 
2Biz said:
I just reread your post. How does it work where you only have one grvity feed tank being supplied with hot and cold water via solenoids? Is it an Erie 2 way that feeds the tank? I guess you need to be more specific on how your system works...Either way, I still think you can do what you want using your rotary as long as its wired correctly.

I'm going to throw this at you too....IF your using an electro switch https://www.kleen-ritecorp.com/p-1728-rotary-switches-8-position-2-stack-metal.aspx Three of the positions are "Make Before Break" contacts...?
Click to expand...

2biz, this is news to me which #'s on that switch are make before break?
 
All the 22-28 are make-before-break with the purpose of connecting the motor there. It's to keep the motor from stopping/restarting rapidly when switching between high-pressure functions that are next to each other.
 
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