Tankless Water Heater

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jemz

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May 27, 2012
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154
We are about to pick up our new MH today.  It only has a 6gal water heater.  I assume we need to install a tankless water heater if we want to be able to take a decent shower in it.  Is this something we should have the dealer do?  Or is easy to do?  I want to install one in our summer cabin too.  Should I hire a plumber to do both at the same time?
 
You can take decent showers with a 6 gal. water heater.  Don't let the water just run, take "Navy" showers.  That means turn off the water between rinses using the shutoff on the shower head.  You can easily get 2 showers from one tank of hot water that way and if you need more hot water, use both the propane and electric heaters if so equipped.  Tankless water heater have not proved too practical in RVs.
 
Right now, the only RV approved tankless water heater that will fit in place of a 6 gl tank type water heater is the Gerard. Many users have the Gerard do not like the quirky operation of it. Atwood should be shipping their new tankless water heaters soon. They will fit where your existing water heater is. They cost more than the Girard but you should be happier with them than with the Girard. Atwood's website won't tell you this but the more expensove of the two also has freeze protection for use in freezing weather. If you will not be camping in freezing weather, you may not need this feature (it's not that much more so I would get it myself just to be on the safe side).

Precision Temp makes the RV500 that has been available for several years. It is more expensive than the Atwoods and you would have to do surgery, possibly major, on your RV to make room for it (it fits in the hole a 10 gl. tank type water heater fits in). It does have a good track record, though. Precision Temp worked with Atwood to design their water heaters so it may be worthwhile to wait for the Atwoods to come out.

Whether you install your water heater yourself or hire a plumber to do it depends on how conficent you are with your plumbing, etc. skills. Any decent DIYer should be able to handle it.

If your cabin has full utilities, you would be better off with a residential model. They are more robust and put out more hot water. Some of those require professional installation to keep the warranty intact.
 
Ned said:
...Tankless water heater have not proved too practical in RVs.

That's not totally true. The Gerards are a bit tempermental and need user adjustment to the odd way they operate but, if installed correctly to ensure adequate water flow, they do work fine in all but extreme weather conditions most campers won't encounter . Not all RV manufacturers that have been installing them in new RVs have been installing them correctly (water flow is inadequate) and not all dealers are telling customers how to use them (and who reads instructions?). The Precision Temp RV 500s have a fairly good track record but most people are turned off of them by their cost. Since Atwood puts out decent products and Precision Temp helped them design Atwood's new tankless water heaters (the internal components look similar, if not identical, to the RV 500's; they are just designed more compactly), the new Atwoods should be good products.
 
I assume we need to install a tankless water heater if we want to be able to take a decent shower in it

Before spending the money for tankless, I would sugggest you try the water heater in the mh. RV water heaters are not regulated to lower temperatures like at a stick and brick so you will mix a lot of cold water with the really hot water from the water heater. DW and I can take back to back leisurely showers (shutting water off between rinses), including shampooing hair and still have hot water left to do dishes immediately after.

Enjoy your new motorhome.
 
Lady Fitzgerald said:
The Gerards are a bit tempermental and need user adjustment to the odd way they operate.... Not all RV manufacturers that have been installing them in new RVs have been installing them correctly (water flow is inadequate) and not all dealers are telling customers how to use them (and who reads instructions?). The Precision Temp RV 500s have a fairly good track record but most people are turned off of them by their cost.

All that says they aren't too practical in an RV :)  The standard gas/electric water heater just works, and works as you expect it to.
 
Ned said:
All that says they aren't too practical in an RV :)  The standard gas/electric water heater just works, and works as you expect it to.

Again, not necessarily. The RV500 and the Atwoods are used the same as a tank type water heater; one blends hot and cold water to adjust water temperature. Also, the water temperature of a tankless will stay consistant while using instead of gradually getting cooler as it is used.

Despite the quirks of the Gerard, many people will be willing to put up with them to get endless hot water at a lower price. I'm not one of them and would prefer the more expensive of the two Atwoods or even an RV500. Most complaints I've seen on the Gerard had to do with the owner not using it properly or the installer not ensuring adequate flow (such as removing flow restrictors, upgrading the pumnp if too slow, etc.). A couple have to do with cold weather operation; the two speed burner keeps hunting at certain temperatures, causing fluctuations in water temperature. I've seen more reports from owners happy with its operation.

I've heard only two complaints on the RV500. One was by a clown who bought his used from a mobile repairman who claimed it came from an RV owned by an elderly woman who was frightened by the sound of the flame coming on (if that wan't a phony story...). The other said his worked fine other than having to have a board replaced a couple of times. I've seen numerous reports of satisfaction with the RV500. Gary Bunzer, the RV doctor, tested the unit and gave it a good report.

Not everyone will consider a 6 gl tank type water heater to be adequate (including me). Some people want longer showers than you. Some, like me, need a longer shower just to get the kinks out in the morning. There is no way any more than one or two people will get enough water from a 6 gl. tank type water heater.
 
odie1234 said:
...RV water heaters are not regulated to lower temperatures like at a stick and brick so you will mix a lot of cold water with the really hot water from the water heater...

That is only true of Atwood's Exothermic water heater. It is a ten gl. water heater that heats water up to around 180 degrees and has a mixing valve on the back that tempers the hot water with cold water, producing the equivalent of a 16 gl. water heater. I've seen quite a few reports on problems with the mixing valve. Other tank type RV water heaters normally do not produce water any hotter than in an S&B unless the thermostat has been tampered with or is malfunctioning.
 
I might consider a tankless if and when my 6 gallon needs to be replaced.  Endless hot water sounds great, but I have to say that I am plenty happy with my little 6 gallon Atwood.  I have found that the added Hott Rodd electric element I put in helps me have more hot water because I have the thermostat turned to a much warmer setting than the Propane thermostat allows.  Its amazing to me to think about the huge hot water heater we had in our stick house and it sitting there all day wasting electricity.  When we learned that most RV's have a 6 or 10 gallon hot water tank, we thought we could never make it.  (The stick house had an 80 gallon).  We were pleasantly surprised and its nice to know we are using so much less water than we were before.
 
bigpemby said:
I might consider a tankless if and when my 6 gallon needs to be replaced.  Endless hot water sounds great, but I have to say that I am plenty happy with my little 6 gallon Atwood.  I have found that the added Hott Rodd electric element I put in helps me have more hot water because I have the thermostat turned to a much warmer setting than the Propane thermostat allows.  Its amazing to me to think about the huge hot water heater we had in our stick house and it sitting there all day wasting electricity.  When we learned that most RV's have a 6 or 10 gallon hot water tank, we thought we could never make it.  (The stick house had an 80 gallon).  We were pleasantly surprised and its nice to know we are using so much less water than we were before.

Different people have different needs and tolerances and it's not for any of us to say what they should be. My first RV was a travel trailer my ex and I gutted and rebuilt. We didn't want propane because the trailer had already burned once (mostly smoke damage) so we converted it to all electric. We put a 10 gl. residential electric water heater in it and that was barely adequate for the two of us (a 6 gl. propane/electric would have put out the same amount of hot water but I don't think they made the propane/electrics back then; this was in '69). I'm single and older now and I just flat refuse to live that spartan again if there is no need to.

Tankless water heaters aren't for everyone. Neither is living with only a 6 gl. water heater. It boils down to individual choice and needs. For you, it makes sense to continue to use your present water heater since it works and meets your needs.
 
It only has a 6gal water heater.  I assume we need to install a tankless water heater if we want to be able to take a decent shower in it.

Well, I guess it depends on what you call a "decent shower". When we had a 6 gallon heater my wife and I managed fine. Didn't even have to do the "navy" thing (shut off between wash and rinse). But you can't luxuriate for several minutes under the spray either - don't dally!

Try the heater and see how it goes. If you still feel it is inadequate, you might consider replacing it with the Precision Temp RV500 or the Atwood Tankless heater.  Another alternative is the Atwood GE9EXT, which has a 6 gallon tank but blends with unheated water to produce about 9 gallons of usable hot water. It's the same design as the GE16EXT 16 gallon Exothermic mentioned earlier in this thread, but fits in the space for a 6 gallon heater.
 
Thanks for all the information everyone!  We picked our RV up yesterday and we're having fun stocking it today.  I'm surprised tankless isn't more popular in RVs.  I'll do my research and try out the 6gal.  Perhaps we'll get by using the campground facilities, but with 4 little kids (1-7) the convenience of using our own RV might be nice.  I look forward to figuring it all out.  Thanks again!
 
jemz said:
Thanks for all the information everyone!  We picked our RV up yesterday and we're having fun stocking it today.  I'm surprised tankless isn't more popular in RVs.  I'll do my research and try out the 6gal.  Perhaps we'll get by using the campground facilities, but with 4 little kids (1-7) the convenience of using our own RV might be nice.  I look forward to figuring it all out.  Thanks again!

Tankless water heaters for RVs is a fairly new technology. Until two years ago, the only unit suitable for RV use was the RV500. Gerard came out with their stripped down model roughly two years ago; the few manufacturers that have been putting tankless units in tyheir RVs have been doing it on the pricier lines and have been using the Gerard because it is so much cheaper than the RV500. The quirky operation of the Gerard, misinformation (at least one person in this thread alone has assumed all RV tankless water heaters have the same quirky operation as the Gerards), the occasional poor installations, and consumer and manufacturer resistance to new technology, especially when it costs more, have done nothing to popularize tankless water heaters in RVs. Now that Atwood's coming out with their new models, tankless water heaters may become more popular.

Since you already have the 6 gl. water heater, it makes good sense to try it out first. That way, if you don't like it enough to justify shelling out the shekels for a tankless water heater, you won't wonder later on if it was a wise idea to have upgraded. With four growing children, I'm guessing you will want the tankless unit.
 
I'd sure give the coach WH a chance before writing it off.  My wife is known for her long showers and we have no problems.  We do use the "Navy"procedure as described by Ned.
 
Lady Fitzgerald said:
Good question. I recently emailed Atwood asking that and they replied that shipment has been indefinitely postponed.

:(
I wonder what that means?
We did okay with our one night "test" trip, but only DH and I had a shower.  I still think a tankless whater heater is inevitable, but I don't want to get one if a better one is coming soon.
 
WAYS TO TAKE A SIX GALLON SHOWER....
One.    Shower with a friend.  It is a lot of fun and you will save water and really enjoy the shower.
Two.    Take a Navy Shower with a friend.  Both of you get ''wet''.....  You soap down the friend and let the ''friend'' soap you down.
Three.    Rinse off the friend and let the friend rinse you off....  (very efficient I might say)
Four.    You dry off the friend and let the friend dry you off.  (I also suggest baby powder and baby oil as appropriately applied)
Five.    Go buy one of those shower heads with the ''cut off button thingie'' on it so you can turn off the water while soaping down.  We have one and we love it. 
What happens after the ''Shower with a Friend'' is up to you.............  Good Luck.......cj...

Ten cents for this valuable suggestion and you can pay me when you see me next time ....


Go to Arlington sometime and say a prayer at the Tomb of the Unknown................cj............. nuff said ...
 
could you add, say to just the shower, a small 110volt instahot in line with the 6 gal onboard heater?
 
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