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Author Topic: RV tankless water heater  (Read 2365 times)

e327

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RV tankless water heater
« on: May 30, 2016, 10:29:30 AM »
why won't my RV tankless water heater come on

Utclmjmpr

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Re: RV tankless water heater
« Reply #1 on: May 30, 2016, 10:37:47 AM »
 This question ranks right up there with ,,,,"where did I leave my crystal ball?".>>>Dan
« Last Edit: May 30, 2016, 06:52:06 PM by utahclaimjumper »
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Rene T

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Re: RV tankless water heater
« Reply #2 on: May 30, 2016, 10:48:55 AM »
What Dan was referring to is we need just a little bit more information. Like maybe year, manufacturer, model number,  what have you tried so far, has it been working good up until now.
« Last Edit: May 30, 2016, 10:51:02 AM by Rene T »
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John From Detroit

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Re: RV tankless water heater
« Reply #3 on: May 30, 2016, 02:41:08 PM »
Ok, Tankless Water heaters are typically Propane only, However they may (Should in fact) be using 12 volt electrical for several function.. Like opening the gas valve and lighting the flame. 

Here is an opration description for a 12 volt controlled Tankless DSI water heater

Water flows, closing a flow switch (like a sail switch on a furnace, in fact, other than being waterproof, it is identical)
IF thermostat is cool, then the control board opens gas vale and inititates sparking (ignition)
Flame sensor sends "I'm hot" signal back to control board and flame continues tilll...

Thermostat says I"m hot  or water stops flowing.. (either one).

Possible issues:

Water flow too slow
Switch (flow) bad
Thermostat bad
Mother board bad
No propane
Propane valve bad
Ignition points set too far apart (Very popular error Half the DSI products I've worked on had this). (two out of 4)
Bad flame sensor
Bad control board again (Flame detector circuit)

And of course, no 12 volts (blown fuse, bad connection, broken connection, Switch OFF)
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Arch Hoagland

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Re: RV tankless water heater
« Reply #4 on: May 30, 2016, 04:04:37 PM »
A friend of mine had the same problem.

She discovered she had turned off her propane tank and forgot to turn it back on.

Is yours propane or electric?
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Raylc

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Re: RV tankless water heater
« Reply #5 on: May 30, 2016, 07:57:08 PM »
They also make them that run on diesel. Aqua Hot. That is what we have.
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steve407

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Re: RV tankless water heater
« Reply #6 on: May 31, 2016, 07:43:16 PM »
Ok, Tankless Water heaters are typically Propane only, However they may (Should in fact) be using 12 volt electrical for several function.. Like opening the gas valve and lighting the flame. 

Here is an opration description for a 12 volt controlled Tankless DSI water heater

Water flows, closing a flow switch (like a sail switch on a furnace, in fact, other than being waterproof, it is identical)
IF thermostat is cool, then the control board opens gas vale and inititates sparking (ignition)
Flame sensor sends "I'm hot" signal back to control board and flame continues tilll...

Thermostat says I"m hot  or water stops flowing.. (either one).

Possible issues:

Water flow too slow
Switch (flow) bad
Thermostat bad
Mother board bad
No propane
Propane valve bad
Ignition points set too far apart (Very popular error Half the DSI products I've worked on had this). (two out of 4)
Bad flame sensor
Bad control board again (Flame detector circuit)

And of course, no 12 volts (blown fuse, bad connection, broken connection, Switch OFF)

Since we're on this subject, I have a Girrard tankless and my problem is it's either scalding or ice cold.  There doesn't seem to be a middle ground in the shower where you can get it one temp.  The water heater switch has 2 positions: Auto and Low.  I've tried both but it just does the same thing.  Scald for 30 seconds, then ice cold for 30 seconds.  I was told the temp was suppose to be regulated by water flow: i.e., the more water you run the cooler it gets, but that seems to make no difference either.  Anyone have ANY ideas?   Thanks in advance.
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glen54737

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Re: RV tankless water heater
« Reply #7 on: June 01, 2016, 07:21:07 AM »
@steve407 I have one of those too. It sounds like it is cycling, there is a high temp shutoff that is stopping the burner when the water temp gets to 140 then as it cools it relights the burner. Try putting it on low and turning the hot water on full if it still does this you need to draw more hot water to get the temp down try turning on the sink hot water to control temp I realize this uses a lot of water.
The newer model has a rheostat that will allow better control of the burner they will upgrade you for a price i think it was about $300 and you need to return the old one.
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steve407

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Re: RV tankless water heater
« Reply #8 on: June 03, 2016, 08:48:14 PM »
Thanks for that info. I'll give the additional water issue a try but sounds like the upgrade is what I need.  I'll contact them and see if it is still available. 

I appreciate the help!!

Steve
Someplace new is always just around the next curve. 
2012 Coachman Pathfinder Elite 39' DP, AirForce1, BlueOx Towbar
2012 GMC Terrain Toad
DW=She who must be obeyed
and Freckles the Dalmatian

Dick107

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Re: RV tankless water heater
« Reply #9 on: January 24, 2018, 03:36:46 AM »
Help me
Rinnai RUC98iN Tankless is used on RV?

Dick107

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Re: RV tankless water heater
« Reply #10 on: January 24, 2018, 03:39:36 AM »
I found a review article: speedfinal.com/best-tankless-water-heater-for-rv/ about best tankless water heater for RV but I don't know item Rinnai RUC98iN Tankless used on RV?