New Kuma water heater worked great for a season - and now won't heat through the heat exchanger Removed the coolant hose (input)- turned the engine and no coolant being pumped. Replaced the thermostat, and still no luck. Engine has not overheated , but still no luck on the coolant - please don;t tell me I need to replace the coolant pump....
Water Heater - Heat Exchanger Problems
- Thread starter spadaforaj
- Start date
If the coolant pump doesn't work, your engine overheats.
Is there anything like a thermostatic valve on the hot water tank ?
So it's unlikely that the pump is your problem.
Is there anything like a thermostatic valve on the hot water tank ?
There is definitely a pressure relief valve, but I don;t know what a thermostatic valve looks like - I should have posted a picture
Was the water heater not winterize last year? I’m guessing it is a simple air block. A utility pump and a container of coolant is your best friend to resolve that.
Don't buy anything unless you can prove you Kuma water heater is broken.
The only way antifreeze can cross over into your potable water is through a leak in the heat exchanger tubing.
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Thanks - just pump some coolant into the intake until it comes through on the outlet pipe ?
Was the water heater not winterize last year? I’m guessing it is a simple air block. A utility pump and a container of coolant is your best friend to resolve that.
If you can set that up, that's and excellent way to check for any obstruction in the heat exchanger tubing.
While you're at it, if you can get a few pictures of the inlet and outlet connections on the tank, that will tell if there is any type of thermostatic device on there.
Hi all - found this image in an older forum - this is what is on mine - should I also start by replacing this mixing valve ? I understand they are no longer available. Anyone have a recommendation for a replacement model (that woudl be relatively easy to install ?
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In my opinion, they are a complete waste of money. If you have one, remove it and install your hot and cold connections without one.
Your tank has the ability to produce water at temperatures up to 180° from the engine but rarely is that temperature available once a little cold water enters the tank. If one is so helpless as to not be able to control the temperature of the hot water outlet, being out on the water is the LAST place they should be.
For 10 years we had out Watts mixer value set to not mix (ie be damned, give us water as hot as it gets). Yup when the hot water initially came out of the tap at that 180° the skin from my old and decrepit body was almost pealed off when I washed my hands or showered. By the time I finally got it adjusted to a comfortable temperature and volume (ie mixed manually at the hot and cold faucets) I had wasted a goodly portion of that tank of hot water and also wasted a goodly portion of my library of curse words. As the cold water replaced and thus cooled the hot water in the tank, the faucets had to be continuously (manually) adjusted to maintain a comfortable temperature at the tap.
This year I set the mixer valve so I only need to open the hot water faucet. Glorious 110° temperature water no matter which of our 3 methods of heating the water is used (120V (approx 140°), engine (approx 180°) or Espar hydronic furnace (approx 160°). Of course the water in the tank has to be >110° or you get whatever is left.
Mix the water automatically at the outlet of the tank or mix it manually at the end usage point and practice your good sailor vocabulary.
Your water tank, your choice.
This year I set the mixer valve so I only need to open the hot water faucet. Glorious 110° temperature water no matter which of our 3 methods of heating the water is used (120V (approx 140°), engine (approx 180°) or Espar hydronic furnace (approx 160°). Of course the water in the tank has to be >110° or you get whatever is left.
Mix the water automatically at the outlet of the tank or mix it manually at the end usage point and practice your good sailor vocabulary.
Your water tank, your choice.
I ran into a similar problem. Engine warmed up, no hot water from water heater. My solution was simple once discover. Looking top-down, I couldn't see that the water supply bypass was closed. Dope slap! When I winterized I needed to bypass the heater. Come Spring I forgot to open it up again. It may not be your solution, but it was mine.
I did that once…even replaced the thermostat/high temp limiter…still no hot water…later realized I opened 2 of the 3 the valves for bypassing my WH to winterize it.
Greg
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Oh.... I feel your pain. I once installed a brand new LED bow nav. light pod and rewired all of the electric in a Macgregor 22...right before I put my boat up for the winter. Spring comes and the lights don't work. Tested the voltage at the lights and had 13V.... Tested the voltage at the battery, same....so I replaced my brand new LED lights.... still no joy. Ripped out my new wiring and started over.... still no joy.... flipped the switch to the nav lights only to notice the voltage dropped to 2V at the light when the switch was flipped..... After much hair pulling realized I had some corrosion at the battery terminal .... brushed it off.... JOY! And much internal turmoil for all the wasted time and money I had spent chasing a ghost.I did that once…even replaced the thermostat/high temp limiter…still no hot water…later realized I opened 2 or the valves for bypassing my WH to winterize it.
Greg