Not sure what happened. We were leaving a shopping center and heard an awful racket. The aquahot exhaust tore clear off. There is a 2 foot stub coming out of the aquahot but hte rest fell off and got mangled. It took us a little bit to figure out what was scraping. I removed the mangled mess and saved it. It looks like standard steel? tubing but there is some kind of tiny resonator or muffler. Anyone know what that is? I was thinking I might just go to a midas type place with specs. The existing stub means I could just piece something together myself and use one of those exhaust clamps to tie the old and new together.
You need to check and make sure the tank was not damaged. If you hit something it probably damaged the tank inside and that means a new unit.
I think that's highly unlikely. The pipe coming from the unit is still attached and holding firmly. We still have hot water with the electric element. There is a lot of corrosion on the pipe near where it broke. I think it was just rusted through.
Good thing. If you bump it hard enough it does cause it to leak. It is screwed into the bottom so you will need to get that stub out and then build a new one. Rudy might be able to get you the specs.
Piku,
Take old pipe to auto exhaust shop and have new one made from that pattern. Do not worry about the muffler. No other manufacture including Newell and Prevost converters uses one and it is not a Aqua Hot part or specification.
Install the largest diameter pipe you can. Larger diameter than the original is just fine as it breaths better.
Keep exhaust run down hill or flat from heater to exhaust end. Lots of hot humid exhaust that can condense if the run is long enough and will collect if run is up hill or has a low spot between heater and exhaust end.
Use a tip that is straight out rather than turned down. Tip should not be located under a slide.
Before we get moving tomorrow I'll dig in and look for leakage to be sure. That would make this really expensive :( The exhaust shop is what I was thinking too. The aquahot manual says to use black iron pipe?! I would think that woudl be very heavy and expensive for that long of a run. I'll just try to replicate what is there. If it lasted 15 years, it is good enough.
Standard exhaust pipe is fine. Most of us go to 2" for replacement.
Piku,
The nipple screwed into the bottom of the heater, the 90 degree elbow screwed onto the nipple and the nipple screwed into the elbow are made of iron pipe. The exhaust pipe is regular exhaust pipe available at any auto exhaust shop. The shop flares the end of the pipe so it will slip over the nipple and can be clamped.
Pressurize the tank with a radiator pressure tester or by bringing the heater up to temp. If exhaust penetration is leaking, it will drip onto the ground below the exhaust elbow and the elbow will be damp or wet with coolant.
A coolant leak elsewhere that drips out the exhaust hole in the floor under the heater normally does not get on the elbow of the exhaust.
Watch for loss of engine coolant also. The engine coolant also loops through the aquahot totally separate from the furnace coolant.
Just got sort of done replacing the exhaust. The nuts on the clamp holding the old pipe on the 1 1/4" cast iron nipple each snapped when removal was attempted. Even after the clamp was removed, the old exhaust was stuck tight so I used a chain cutter to break it at the nipple and then I used a dremel tool cutting wheel to score a line over the remaining piece. Once i cut deep enough it just snapped and popped off leaving a clean undamaged 1 1/4" cast nipple.
I used 1 3/4" pipe which required only mild expansion using an advance auto rental flaring tool. The flaring tool was hard to use. I had to use a chain vice grips and breaker bar to make any progress. After I expanded it I could then fit it over the 1 1/4" cast iron nipple. I had a local mechanic with a pipe bending/flaring rig create the exhaust bend. He charged $48 for the pipe and work. 6 foot front to rear and 58" from center to side the extra is hanging out and needs to be cut off. I bought a 50 foot spool of 2" wide heat wrap which was $49 and the most expensive part of this project. The spool covered far more of the pipe than the old heat wrap. The heat wrap has been smoking for the last half hour of the aquahot running and smells kind of like french fries. Laying on the cold ground isn't much fun. One of the old hangars broke so I had to cut the nut with a dremel in order to loosen it enough to get the old hanger off. The new hangers are generic and don't fit well. I would consider finding the original hangers but I suspect the one broke (rubber part) which caused the exhaust to fail in the first place.
There was no coolant or wetness on the nipple. We have heat and hot water.
But now I hear a random squeak from the aquahot and you can hear the RPM of the motor change when it happens. Bearings. Has to be. Also the front right wheel is wet on the inside. New seal for the stemco hub is in order. Fun fun.
Btw, the lesson above would be to check your aqua hot exhaust hangers for cracking in the rubber. If cracking, replacing now or suffer my fate.
Seals?