Dual Water Heater

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vmgough

Dual Water Heater

Post by vmgough »

I did not make it clear that I have a dual heater: the switch that has gone open in on the heater below the gas connections and is used when you want 110, I want to wire around this switch and I wanted to know if any of you folks have tried this fix? I do not want to pull the heater if I can help it.
Last edited by vmgough on Sat Dec 14, 2013 10:56 pm, edited 2 times in total.
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whemme
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Post by whemme »

Roy,

I would assume that if the power switch for the water heater was bad, the proper repair would be to replace the switch itself.
Bill Hemme - Spencer, Iowa
E-mail: whemme@earthlink.net
2002 Born Free (Ford E-450 V10) 26' RSB
2016 VW Golf GTI - toad
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Mike Astley
Posts: 171
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Post by Mike Astley »

It confused me at first that the light in the switch would come on briefly and then go out (indicating the water heater had lit successfully). I had planned to add a second light that would stay on as long as the switch was on so we wouldn't leave the water heater on all the time. We adapted before I got around to it.
1999 26RSB
Fort Collins, CO
tmresearch

Water heater light switch

Post by tmresearch »

I just purchased a 2004 BF RSB. My 10 year old Pleasure Way had NO gas, only everything ran on 12 volt or genset. Anyway, the gas is GREAT but like you, I did not want to accidently leave on the water heater in the BF even though the "momentary" red light came on but went off.

You said that you were thinking about adding a "constant" light to show that the water heater was still on (but did not as you got used to the setup). How were going to put in another light to stay on? How to wire, etc?

That brings up a real problem with me as I leave on the water pump by accident as the very small green light on the range hood is just not big enough for these old eyes. (On my PleasureWay, as you exited, the big red light would tell you that you had something on, so I am trying to resolve this for the BF)

I installed a red lighted rocker switch where the old unlighted black rocker switch was to turn on the water pump. However, the new lighted red switch will not perform what I envisioned. It has 3 connections on the back (the old one only had 2 as no need for a lighted rocker switch). I have tried every conceivable combination and can NOT get the rocker switch to light up when the green water pump light AND the water pump is on!!!

I can touch the terminal together where the yellow wires that go to the pump and the green light with a new wire for the red light but here is what happens: Solder them together and no lights (green or red or pump on). Only touch the new wire to conection and ONLY red rock switch comes on. Touch the yellow wires only and the green light and pump come on!!!

I AM NO ELECTRICIAN, BUT NEVER HAD THIS PROBLEM WITH A LIGHTED ROCKER SWITCH ON MY OTHER RV. ANY ADVICE!!!!

COULD IT BE THAT THE 12 VOLTS CAN NOT RUN 3 ITEMS AT ONCE?
GREEN LIGHT/WATER PUMP/RED LIGHT ROCKER SWITCH. NO PROBLEM FOR THE 12 VOLT TO DO SO IN ANOTHER APPLICATION? HAVE NOT BLOWN ANY FUSES BUT WHEN I HAD TO PUT IN A NEW 12 VOLT LIGHTED ROCKER SWITCH ON MY OLD RV, BLEW SEVERAL FUSES (AS I WAS NOT BRILLIANT ENOUGHT TO REMEMBER WHICH WIRE WENT TO TO WHICH OF THE 3 LEADS UNTIL IT WORKED). I KNOW THAT IT IS A "NO NO" TO INCREASE THE FUSE SIZE ON THE BF, BUT WHAT WOULD NOT ALLOW ALL 3 TO RUN AT SAME TIME???

BAFFLED...HELP...THANKS

DALLAS
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Mike Astley
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Post by Mike Astley »

As explanation for a switch with two connections, one side is wired to the 12V and stays "hot" with the 12 V. The other side is switched and only gets the passed through 12V when the switch is "thrown" or "turned on".

For the three connection lighted switch you should either have a diagram of how its wired or you can check it with a meter. if unpowered you can check for continuity between pins as you thrown the switch.

My guess is that they have the light and switch in parallel and there needs to be a ground for the light to work, either grounded through the body of the switch or grounded through the "extra" pin. Without a circuit pic its hard to know, but possibly one pin is meant to be "hot", one pin to go to the pump to power it, and one pin to go to ground to allow the light to turn on.

In regards to the hot water heater, I haven't checked the power but since the switch needs to be on for the hot water heater to run my guess is that there is a continual 12V being passed through the switch and so, if you put a light in series with the "switched" 12V line it would be lit as long as the switch is on.
1999 26RSB
Fort Collins, CO
tmresearch

Water Heater

Post by tmresearch »

Mike, thanks for your info. I have actually added an extra wire and grounded on 1 of the 3 terminals on the lighted rocker switch. No help. Only until I took off the ground end and connected the wire from one of the terminals to the one that had the connection to the 2 yellow soldered wires (1 yellow to water pump and 1 to the green light on range hood) did I have a "ray of hope" as the rocker switch lit up.

But I did not notice when I touched, that the green light and pump went off. So I thought all 3 would work when I attached the 3rd terminal wire back to the terminal with the green light/water pump. Of course the third wire is the red wire: power.

The lighted red rocker switch was purchased at Camping World and no diagram. It was the exact size to fit into the existing slot on the Hood canopy where the other rocker switches are.

One possibility is that I did not have a good ground as I drilled a hole up inside the hood behind the switches and perhaps the hood is aluminum or whatever and not a good ground. Anyway the switch itself is all plastic and I can not see how it would ground itself to the hood?

A conundrum wrapped up in an enigma!!!!!!!

Dallas
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Mike Astley
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Post by Mike Astley »

If the switch is entirely plastic then it is not attempting to ground itself through the body.

I apologize that I'm having trouble following your description. I'm sure I was smarter when I was younger!

Have you positively determined which two leads of the switch are the switch portion i.e. with the old switch off, or removed and the wires attached or jumpered to the two leads, does the new switch turn the pump and green light on and off? And, if so, have you then taken the third lead and run it to a chassis ground point to see what, if any effect it has on the red light?

I can't figure how the red light is intended to work since it obvious works independently of the switch unless the non-switch lead is intended to be tied to ground. If it were tied to 12V it would in parallel to the switch and the switch, being a much lower resistance than the light would preclude the light from lighting.

The mystery of touching the third lead to the switched side causes the red light to light but the pump and green light to go off implies there is a lower resistance to ground through the red light but this, in turn, would mean its achieving a ground path some other way such as through the switch body, which, if all plastic, is not possible.
1999 26RSB
Fort Collins, CO
tmresearch

water pump

Post by tmresearch »

Yes, I have taken the "old" rocker water pump switch off and replaced it with the red lighted rocker switch. The new red lighted switch acts just like the old one and will cut the green light and the water pump on just like the "old" switch when I attach them to 2 separate terminals (out of the 3 terminals on the back of the new switch).

However, my intent was and is to have the red light to come as well when the water pump light and pump are on. I can't seem to get that to occur.

I put a ground wire from the new third terminal switch on the unused terminal and no red light but the green and water pump would come on.

I kept the ground wire on the third terminal and unscrewed the other end from the hole I had drilled inside the hood and touched the terminal where the 2 yellow wires were (which went to the water pump and the green water pump light indicator). When I touched that, the green light and water pump went OFF. However, if I just touched the terminal, the red rocker light would come on but not the green light and water pump?

I have switched every wire to any of the 3 terminals on the back and no success to have all three work at the same time: green water pump light, water pump and red rocker switch light?

Dallas
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Mike Astley
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Post by Mike Astley »

It may be time to wave the white flag and look for a 2 terminal switch with an indicator. I'm not sure why they have 3 terminals but once we figure it out we may find that this switch is intended for a "normally on" switch and the red indicator only lights when you turn the switch off...meaning it is to warn people that the switch is off ...red light warning switch is off vs green light indicating switch is on. Since you want to know when the pump is on, this type of switch would be the wrong one for you.

If you want to slog on then let's continue the conversation.

Do you have a volt-ohm meter and know how to use it? If not, do you have a 12V indicator? (often looks like a pen with a metal tip and an attached ground wire, you attach the ground wire and touch the tip to 12V and the light turns on within the "pen") We could use either of these to troubleshoot what's going on.

Presuming you don't and you have already tried different combinations, answer the following:

Let's label the pins 1,2, & 3. With pin 1 @12V and pin 2 going to the pump and green light (we can use P has short hand), no connection to pin 3, you have switch off: P @0ff and switch on: P @On. No red light in either switch position.

What happened with pin 1 @12V, pin 3: P and pin 2 no connection? With the switch on or off, did the pump work? did the red light turn on?

What happened with pin 3@12V and pin 2: P and pin 1 no connection? With the switch on or off, did the pump work? Did the red light turn on?

You said "I put a ground wire from the new third terminal switch on the unused terminal". What unused terminal? How do you know this terminal is a ground connection?

You said "I kept the ground wire on the third terminal and unscrewed the other end from the hole I had drilled inside the hood". Not sure what this means as just before you said the wire had been connected to a terminal. Can you explain?

When you said "I touched" did that mean physically touching with your finger or ?

Thanks!
1999 26RSB
Fort Collins, CO
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whemme
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Post by whemme »

If you want to add a separate indicator that will stay illuminated when the water heater rocker switch is on, then this is one way to accomplish this job.

1) Determine which terminal on the existing rocker switch has 12 vdc on it when that switch is on.
2) Then connect one terminal of your add-on 12 vdc indicator lamp to that terminal.
3) Then connect the other terminal of the add-on 12 vdc indicator lamp to system ground. System ground is not available at any terminal on the rocker switch. You will need to connect that indicator lamp terminal to the metal frame of the Parallax 7345 power center which is system ground.
Bill Hemme - Spencer, Iowa
E-mail: whemme@earthlink.net
2002 Born Free (Ford E-450 V10) 26' RSB
2016 VW Golf GTI - toad
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Mike Jean Bandfield
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Post by Mike Jean Bandfield »

whemme wrote:If you want to add a separate indicator that will stay illuminated when the water heater rocker switch is on, then this is one way to accomplish this job.

1) Determine which terminal on the existing rocker switch has 12 vdc on it when that switch is on.
2) Then connect one terminal of your add-on 12 vdc indicator lamp to that terminal.
3) Then connect the other terminal of the add-on 12 vdc indicator lamp to system ground. System ground is not available at any terminal on the rocker switch. You will need to connect that indicator lamp terminal to the metal frame of the Parallax 7345 power center which is system ground.
Hmm. And if you want a single bright red light that will get your attention if the water pump, water heater, battery, furnace, etc is left on: Add a diode between the lamp and switch in Bill's description and add a wire and diode between the 12vdc side of any switch in the RV to the indicator lamp. The diodes will prevent currents from flowing between the devices but will each cause the single lamp to light giving you a light as bright as you need it to be. :idea: You could add a buzzer too but that might be a little too annoying :)
Mike & Jean
2005 26' RSS Diesel
Ray

Post by Ray »

OK - You totaly lost me on the diode thing? I know what diodes are and what they do - just dont understand the reason to include in Bills hook up.
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whemme
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Post by whemme »

Ray,

What Mike is suggesting is that a single red indicator could be used to illuminate whenever any of the switched functions he referred to were left on. However for a single indicator to do this properly, the individual circuits to the single lamp would have to have an isolation diode inserted in each switched line for it to work correctly.

See an example wiring diagram below showing the necessary isolation diodes. If any one or more of the switches were left on, the red warning indicator would stay illuminated.
Attachments
3 Circuit Warning Indicator Wiring Schematic.png
3 Circuit Warning Indicator Wiring Schematic.png (15.9 KiB) Viewed 13804 times
Last edited by whemme on Wed Dec 11, 2013 8:46 pm, edited 4 times in total.
Bill Hemme - Spencer, Iowa
E-mail: whemme@earthlink.net
2002 Born Free (Ford E-450 V10) 26' RSB
2016 VW Golf GTI - toad
Ray

Post by Ray »

Bill - Got it - Understand now

I allways did do bad in school on reading comprehension skills - LOL

Thanx
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Mike Jean Bandfield
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Post by Mike Jean Bandfield »

Bill,

Thank you! That is a very nice schematic. Nothing like a picture to make things clear. I've used it as the basis for illustrating Dallas' switch; 'hope you don't mind the plagiarism.

Dallas and Mike,

Could this be the configuration of Dallas' switch? If so, this would be the connections you need.

Mike
Attachments
Water Pump Switch.JPG
Water Pump Switch.JPG (39.57 KiB) Viewed 13786 times
Mike & Jean
2005 26' RSS Diesel
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