frozen pipes

[Roger Baldwin]

Hi, We were away from our coach for two days and the breaker tripped and the batteries went dead and the coach water system froze solid. (We are in Colorado). After we thawed everything out we find water pouring out of the aqua hot from the bottom.  Has anyone else had this problem?  Not sure if it can be repaired or if the entire unit needs replaced, an expensive proposition.  We aren't sure about other leaks at this point because we can't get water through the pipes.  We are now camping in a nice "tent" with no water.  John C. called and told us it probably has to be replaced.

[Dan Young]

When I bough my coach it had not been winterized properly it had to be replaced

[JimDyer]

repaired. We cut out the split section and silver soldered it back together. Took about 14 hours of labour, but it works perfectly now.

[JimDyer]

Roger, if you get the shell replaced it will be just under $10,000 and the work done locally will be roughly the same as if you find a local shop to fix it for you.

On edit: But you won't have spent the $8000 for a new shell.

[Sean Donohue]

You might want to read this first. In this RV.Net thread, they cut out the damages section of the "coil". If it was me I would replace the copper with Stainless Steel which will have a higher burst rating.

http://www.rv.net/forum/index.cfm/fuseaction/thread/tid/24289362/srt/pa/pging/1/page/1.cfm

[Gil_Johnson]

This should be covered by your standard coach insurance policy under comprehensive.  Worth checking into.

[Bill Sprague]

[quote author=]Hi, We were away from our coach for two days and the breaker tripped and the batteries went dead and the coach water system froze solid. (We are in Colorado). After we thawed everything out we find water pouring out of the aqua hot from the bottom.  Has anyone else had this problem?  Not sure if it can be repaired or if the entire unit needs replaced, an expensive proposition.  We aren't sure about other leaks at this point because we can't get water through the pipes.  We are now camping in a nice "tent" with no water.  John C. called and told us it probably has to be replaced. [/quote]
Roger,

You have suffered the ultimate AquaHot catastrophic failure.   You have my full sympathy.  

I don't personally know him, but Orman Claxton is a BAC member and is considered by many to be the club's AquaHot expert.  I believe he is factory trained.  His contact information is in the club directory.

Another resource is Roger Burke.  He has built a repair and parts business around diesel RV furnaces.  He has coached me through two repairs.  He has a website (http://www.rvhydronicheaterrepair.com/), encourages active participation in a focused forum similar to this one, stock parts and is generous with his knowledge.  I think he has rebuilt units.  If he has not fixed a AquaHot with your failure, he will probably know who has.  

Good luck with your repair!

[JimDyer]

You might want to read this first. In this RV.Net thread, they cut out the damages section of the "coil". If it was me I would replace the copper with Stainless Steel which will have a higher burst rating.

http://www.rv.net/forum/index.cfm/fuseaction/thread/tid/24289362/srt/pa/pging/1/page/1.cfm

That was me. Nice to know somebody reads this stuff. I chose to stay with copper for five reasons.
Winding a SS coil would be a major deal vs copper which is soft.
Half of the coil was still bedded in the thermal cement and allowed us to pull against it to keep the copper coil tight. A new coil would be a lot harder to do.
We only lost about 3% of the coil this way. The thermal coefficient of SS is lower, meaning we'd have lost heating ability by going to SS
If there ever was a next time, copper is easier to repair.
We didn't need to buy the copper.

Jim

[Jim Moncrief]

Roger,
I don't know where you are in CO, but I believe Hydro-hot/Aquahot is located in the Longmont area. Google them. I have had various leaks and fixed them, but judging from your description it sounds expensive. Best of luck, and I hope you get it fixed soon...and economically. Jim :

[Sean Donohue]

Nice post about the repair Jim. One of my assumptions was the Wort coolers were close to the same demensions as I know winding SS is a lot tougher to do without cracking or deforming it. Your reasonings are solid advice. However, I would trade the thermal efficency for a bullet proof product...

http://www.nybrewsupply.com/wort-chillers/shopby/3_8_stainless_steel.html

[Joel Weiss]

I don't have a dog in this hunt since I have a Hurricane system and not an AquaHot, but I am curious about the disaster you had.  With a Hurricane the circulating heating liquid is normal automotive anti-freeze.  The only location in the system where there is any water involved is at the hot water heater where the Hurricane's liquid circulates through it to provide heat the water and in two heat exchangers ahead of the hot water tank which are pre-heaters.  If we had a frozen coach situation we would damage the water heater and maybe the heat exchangers but they are fairly inexpensive to replace.

Obviously, an AquaHot must be a lot different.  Out of pure curiosity I am interested in knowing how it works.

[Edward Buker]

If I had lost my water coil due to freezing but the rest of the system was O.K. I would probably consider something like adding a marine stainless water heater. You are looking at a $300 to $900 investment as opposed to $10k. I had put a 6 gallon version in an old GMC motorhome and had plenty of hot water. I have also had one in a boat that gave the same excellent results. They heat to 160 degrees so the capacity when mixed is signficantly greater. The ones in the link draw 6 amps at 120V and has a mixing valve. Some draw maybe 10 to 12 amps. Many versions also have a coil heat exchanger to plumb in a loop from the engine. The downside is you would lose some storage space in the bay, and you lose the ability to heat with fuel oil unless you took a novel approach and used the tankless coil as a heat load for one of the zones from the aqua hot. Perhaps the storage bay zone. The upside is cost, shorter runs for the hot water lines, and being installed in the insulated bay it would be more difficult to freeze. Food for thought.... Later Ed

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http://www.westmarine.com/webapp/wcs/stores/servlet/SiteSearchView?Ne=2050643&Ns=Most Popular|0&beginIndex=0&langId=-1&storeId=11151&page=CategoryDisplayLevel1&N=377+710+2050643&catalogId=10001&pageSize=10&sType=SimpleSearch&viewTaskName=SiteSearchView

[JimDyer]

The heat exchanger idea was where I was headed when I bought the coach........but.the dealer had disassembled it and put the loose parts in a box in the compartment. Looking it over, it was obvious that soldering the tube would be the easy and cheap repair.

It would be easy to put in a heat exchanger using either the bathroom loop or, if you have one, the basement heating loop. A flow switch to turn on the loop pump when the tap is open, then a mixing valve to limit the high temperature. And repairs in future would be simple if it's a stock heat exchanger.

[Edward Buker]

I'm not sure if there is enough zone flow from the Aquahot zone pump and BTUs in that flow to take cold tap water and provide an 80 degree rise with what I have in mind as a heat exchanger. I think you would need some kind of resevoir and thermostat system to keep a resevoir at temp to have enough thermal mass. Probably 6 gallons would be plenty under these circumstances. I know when I turn on a zone and wait for the air flow to feel warm at a heat vent, it has quite a lag time.

 Jim, maybe we are talking the same language and the exchanger you have in mind has a few gallon capacity.

Later Ed