Hydro-Hot bites the dust. New or rebuilt?

[Sandy Swede]

I drew the short straw on the Hydro-Hot (HHE200 09E). It has a split/crack in the boiler fluid coil loop - leak is very apparent when up to operating temp. A rebuilt unit (my "core" sent in) is $6,400 with freight, one year warranty, and about 5 weeks for the round trip. A new Aqua-Hot 450 is $8.2k with freight, two year warranty, and about 2 weeks for delivery. At this point, I am leaning to spending the extra $2k for the new Aqua-Hot. Everything new plus a 2-year warranty. If I rebuild my old one, I will still have some parts that are 15 years old. Your take on this?
BTW, this does not include removal and installation labor of about $1,500.

[96 Wideglide]

Tough call!

Is your H.H old enough to have the seperate set of thermostat's for the electric element/ diesel burner? That is a big plus over the newer AH 450!

[Sandy Swede]

Originally Posted by 96 Wideglide

Tough call!

Is your H.H old enough to have the seperate set of thermostat's for the electric element/ diesel burner? That is a big plus over the newer AH 450!

Not sure, can you elaborate?

[96 Wideglide]

Older units had seperate 'cut in' thermostats. I f you were on shore power, you could leave both electric element and diesel burner switched on and the burner would only fire if the elec element couldn't keep up.
Newer AH models share the same cut in thermostat. When boiler fluid temp drops to a preset temp, if both switches are on, both heat sources are starting up at the same time.

(edit).. Forgot to add, the cut in thermostat that turns on the diesel burner was set a few deg lower than the electric one, giving the electric side a chance to raise boiler temp on it's own, during low demand situations.

[vito.a]

Carl (loranimal) recently rebuilt his Aqua Hot boiler.
http://www.irv2.com/forums/f115/aqua...es-436421.html

Another member bypassed his until he could get to CO to have it rebuilt.
http://www.irv2.com/forums/f115/aqua...ng-454290.html

Roger Berke is also great source for parts and advice.
http://www.rvhydronicheaterrepair.com/index.htm

[153stars]

How closely has it been looked at. There are some hoses attached that could leak into box. Icluding radiator the overflow hose ,mine was split only leaked at full temp. It ran into box. I replaced with reinforced fuel\coolant rated hose .Hose that was on it was crap.

[Sandy Swede]

96 Wideglide: Thanks for the explanation of cut-in thermostats.

vito.a: I appreciate the links, thanks.

153 stars: It has been diagnosed by an Aqua-Hot authorized servicer/dealer after running several gallons of boiler fluid through on two occasions. He claims the crack/split is in the (copper ?) coils through which the boiler fluid circulates. However, I will ask him about the hose. Thanks for sharing that - good tip. I intend to retrieve my old unit and perform some 'forensic surgery' to verify his claim and find out if there are any parts worth salvaging. Although I previously noticed leaking of boiler fluid, I originally brought it in because I knew the igniter coil was bad and possibly one of the circulation pumps. The ignition coil itself costs about $500 new and I believe the circulation pumps go for about $400.

[153stars]

From the people that have operated on them it's usually a neck\pipe or cap housing to tank that leaks.You should be able to use a radiator pressure tester to add pressure and not get burned or make up some plugs and use if it's removed. Aquahot are new to me so I've searched and read every post I can. One guy even rewrapped a whole new water coil. Gave me a butt pucker thinking about that one. Good luck. Maybe some of the AH surgeons will chime in soon.

[shootist]

The coil is for your fresh water. Another loop for the engine antifreeze. The coolant is in the tank, I'm a little confused as to what is leaking to where. A tank leak could be repaired externally.

[Sandy Swede]

Determined to my satisfaction that the leak is not repairable. I've decided to bite the bullet and order a new Aqua-Hot. I will update as things progress.

Thanks for your input.

[super_rep]

If it's not a big split and is accessible , find a local air conditioning repair and ask them to silver sodder the crack. If the AC repair guy is any good, he can fix a split and it will hold pressure.

[Sandy Swede]

Originally Posted by super_rep

If it's not a big split and is accessible , find a local air conditioning repair and ask them to silver sodder the crack. If the AC repair guy is any good, he can fix a split and it will hold pressure.

Great suggestion, but I don't want to risk the cost of removal and installation labor ($1,500) if an attempted repair of the crack does not pan out. However, you give me a good idea in that a repair of the crack(s), if successful, would enable me to recoup some of my expenses by selling the used Hydro-Hot. Of course, I would have to spend $500 to replace the igniter coil which is also shot. And perhaps $400 for a circulation pump. Given the cost of a new Aqua-Hot ($8k) or a rebuild of my unit ($6.2K), I should be able to get a couple of grand for a working unit, albeit an old one with no warranty.


I think my experience should be a cautionary tale for anyone with limited financial resources who is contemplating buying an older DP. I am blessed to be able to stroke a check for the cost of this without being placed in financial jeopardy.

[96 Wideglide]

Do you always use a good water pressure regulator?

[Sandy Swede]

Originally Posted by 96 Wideglide

Do you always use a good water pressure regulator?

Always. Wouldn't leave home without it.