Hydrohot leaking...

[John Ziomek]

Hola!!!!  fellow  Beaver owners....and friends.
Recently I have discovered a small puddle under my coach where the hydrohot resides.  Felt the fluid and seems to be the boiler solution I put in the reservoir.
Checked and it was low (recently had topped it off, approx 2 months ago).
Added more solution to proper level.
Removed front cover to try and chase the leak, saw a little residue but nothing that would indicate a leak.

Not sure where to go from here......welcoming any advice or suggestions.

This is on a 2006 40' Monterey....the hydrohot unit is HHE-200-09E-12vdc

Thanks....

JZ

[Gerald Farris]

John,
The most common location for a leak like the one you mentioned is where the hose from the recovery bottle reservoir (where you add boiler fluid) connects to the AquaHot unit itself. The hose deteriorates from the heat, and you can usually just cut off 2 or 3 inches and reinstall it.

Gerald 

[Dennis Belfils]

As Gerald said, check the tank hose first, it not, remove rear access panel by crawling under the coach. There is plenty of room when the slide is out. There you can check all the hoses & fittings that can't be gotten to from the front. Ours turned out to be a cracked brass fitting on the return line.

[David T. Richelderfer]

When our Aquahot developed a leak, the leak started very slow and over a few months got worse and worse.  When I had the unit annualed, the tech found that the O-ring sealing the electric water-heating element had deteriorated.  We had the tech replace the element with a new one - cost was about $30.

Ours is a 2004 Marquis with an Aquahot - AHE-100-02S.

[Bob Stone]

Another simple thing to check, I like simple and inexpensive, is the radiator cap. The seal in the cap deteriorates.

[John Ziomek]

A very "BIG THANKS" to all.  I will definitely follow all recommendations with a follow up.
Again THANKS!!!!!!

[John Ziomek]

Have followed all suggestions.....removed front and rear access panels....no sign of a leak.
The solution is coming through an opening under the unit where a larger pipe, 1 1/2", goes all the way to the rear of the coach.  I'm going to guess this has something to do with warming up the engine block.
We haven't been using the hotwater for a few days and the puddle underneath seems to be drying up.
As of this moment I have no idea how to access the inside where the pipe ties in or any clue what to do going forward...
Any suggestions?

Thanks

JZ

[Harold and Gloria Skipworth]

The large pipe should be the exhaust from the burner.

[Eric Maclean]

John
Do you know when the boiler antifreeze was changed last?
What you may be experiencing is a pin hole in the boiler  itself.
Mine albe it older than yours Jan a series of pin holes in the bottom of the boiler tank and was leaking there bewAre if you run the boiler low on fluid the burner camber will burn through or crack causing a burner fluid leak into the combustion chamber and white smoke like a bad head gasket in an engine .as mine did  I replaced the combustion chamber and replaced the bottom of the
Boiler tank with new metal ( big job and a lot of welding) but a lot cheaper than the ten grand they wanted for a new tank!.
On my unit the domestic hot water loop was external a d had been frozen so I  had to replace it any way the spec called for 160 ft of 1/2 I'd copper tube and I managed to fit in close to 200 ft ( makes a difference in your fuel hot water recovery rate)

Any way see if you can get a cooling system pressure tester and put a 10 to 15 psi on the system sand then hunt down your leak
Check all of the fittings and go from there .
Unfortunately if the antifreeze has been left for years it may have gone acidic and eaten through the bottom of the tank.
Let's hope it's just a fitting get yourself a cooling system pressure tester that will connect to your pressure cap connection ( you should be able to rent one at your local parts store)
10 to 15 psi and give it ten minutes and look for your leak.
Good luck
Eric

[Eric Maclean]

John
As mentioned above the 1 1/2 inch pipe is likely your boiler exhaust pipe and it would appear that if the leak is indeed boiler solution that the tank or a fitting for the coach heating system is leaking .
If it is straight water then your domestic hot water loop is leaking.
Again as above do a pressure test and see what's going on
Unfortunately you may have to remove the whole unit to get to your problem.
Good luck Eric

[Steve Huber Co-Admin]

John,
Consider removing the front and rear panels of the unit and then firing it up. Any connection or hose leak should be evident as the fluid expands.
Steve

[David T. Richelderfer]

I posted earlier about my Aquahot leak experience that turned out to be a deteriorated O-ring seal on the electric water-heating element.  In this case the antifreeze solution also ran out the bottom of the Aquahot's enclosure not revealing the origin of the leak.  When annualed, the tech told me there could be a leak in the boiler tank, copper tubing, etc., and the solution would come out the bottom of the enclosure.  He also indicated the radiator seal could be leaking or the collar that the radiator cap screws onto could also be leaking... and the solution would run down through the enclosure to exit at the bottom not revealing its origin.  My point is you should rule out these "easier" fixes before dismantling the whole unit looking for a more-expensive-to-repair leak.

[Eric Maclean]

Good point David the leak could be anywhere inside the enclosure and as the exhaust exit is the only bottom exit that's where it will run out.
You mentioned the rad cap collar I have read here somewhere that the joint between the collar and the tank has been known to crack and leak.
I still think a pressure test is the best way to find the leak although on mine the burner chamber only leaked when the unit was hot and it was burning antifreeze and sending it out the exhaust.
You also mentioned the electric element seal when I had mine apart the seal was cooked had and would probably have leaked but I replaced the whole element anyway while I was at it.
These things like all things Beaver went easy.
Happy trails
Eric

[David T. Richelderfer]

Eric -  Yes, that collar under the radiator cap can come loose and completely detach from the tank below it.  Mine did.  I remember I replaced the radiator cap but it was really hard to remove.  As I twisted on it with all my strength, instead of the radiator cap turning off the collar, I turned the collar off the tank.  It must have been loose because I don't think a human has the hand and arm strength to break the solder joint.  Although I do remember a man where I grew up who had a small tool box full of one-handled pliers, etc., that he had broken off one of the handles.  Anyways, when that collar detached, we used JB Weld to re-attach it.  That was five or so years ago.