hot water from inverter
- Thread starter Hayden Watson
- Start date
The safety valve is lower than the hot water outlet so it really isn't able to hold air but I did purge it "just in case" after I descaled the inside of the tank.
This was the reason I bought the inspection camera although it is really handy for finding lost nuts and bolt and checking the prop and shaft for fouling and zincs without getting wet, BBRRR!!
How old is the Kumma?
PS - sorry if you mentioned it earlier, but I read most of this yesterday.
PPS - as another check, have you disconnected the flow to the heater and red dot by placing a 3/8" hose from the thermostat back to the engine? This is the way the engines were shipped before they installed the water heater.
PS - sorry if you mentioned it earlier, but I read most of this yesterday.
PPS - as another check, have you disconnected the flow to the heater and red dot by placing a 3/8" hose from the thermostat back to the engine? This is the way the engines were shipped before they installed the water heater.
I bought and installed the WH in 2006. it was sold under the Force 10 name at that time but Kuuma confirmed it is the same unit as their current one.
I will give reinstalling the bypass line to see if I can get the engine up to temp.
Hayden,
1. Our experience is that the heaters most of us C34-ers have are good for anywhere from 6 to 12 years. I just replaced my Seaward S600 last year (2104) for one that was installed when we bought the boat in 1998, and the PO replaced it for this 1986 boat. You could be at the "end of shelf life" time.
2. Look forward to hearing the results.
BTW, I may have sent you this link earlier, but one of our skippers did this, seems to be more like your piping than the one Charles sent you for the Force 10 hater (primary/secondary loops). http://www.c34.org/wiki/index.php?title=Cabin_Heater
Good luck, please keep us posted.
PS Damnit!!! No rum was consumed in the preparation of this post! I should get on the boat!
My original WH lasted for 18 years and finally died due to a leak that appeared to start from rust on the painted outer case that grew into the inner tank. I am hopping that this one will last longer given that the tank and case are all aluminum.
I did a through inspection of this unit inside and out last fall and did not see any corrosion and very little build up which I removed with the descaler. It heats water on 120V in about 30 minutes so my only complaint is that it has never been able to heat from the engine. Last year I got a bug in my bonnet about getting all systems to work properly and this is one of the last. the diagram in the link you provided is exactly what I have and I linked to it in post #29. As I stated, I have been told that given our very cold seawater this is the best way to install.
"I have been told that given our very cold seawater this is the best way to install."
Did the prior system work before you undertook replacement? Did your present installation (#29) ever work from the start?
If not - since your dock neighbor has had success despite the same cold sea water - have you compared his pipe and tube layout to yours? If it does not match yours - are you willing to make changes thus to duplicate his successful pipe and tube layout?
I realize that you are not willing to follow the Kuuma factory design - relying instead on the (so far unsuccessful) layout based on "that which you have been told" - but what have you got to loose by trying these other options?
Charles
ps No more rum for me thus no more couch analysis either.
Did the prior system work before you undertook replacement? Did your present installation (#29) ever work from the start?
If not - since your dock neighbor has had success despite the same cold sea water - have you compared his pipe and tube layout to yours? If it does not match yours - are you willing to make changes thus to duplicate his successful pipe and tube layout?
I realize that you are not willing to follow the Kuuma factory design - relying instead on the (so far unsuccessful) layout based on "that which you have been told" - but what have you got to loose by trying these other options?
Charles
ps No more rum for me thus no more couch analysis either.
Possibly unrelated, given that your Red Dot works, but I'm amazed that you get any hot water our of your engine with 3/8" OD fittings.
It's 3/8" ID hose, 'cuz that's the size of the connections on the engine thermostat housing. Most boats expand that to 5/8" to run to the water heater. There have been thousands of Universal M25 engines (21 hp) installed in boats and that's how they work. Mine works just fine, 28 years on.
Is the heater and WH wired in series, or in parallel(both fed through a TEE fitting)?
WH and RedDot are in series. WH gets water first with in at 140F and out at 137F. the RedDot gets what is left, in at 137F and out at 100F or lower.
For some very unexplainable reason, the WH exchanger does not pull any heat.
Mr. Watson is convinced the flow arrangement (the horizontal layout) is just fine and the water heater evidently does not have temperature compensation control.
We do not know about the vertical layout. If the water heater is above the coolant reservoir and the Red Dot is below then wouldn't that explain why the water heater does not heat whereas the Red Dot does.
Charles
We do not know about the vertical layout. If the water heater is above the coolant reservoir and the Red Dot is below then wouldn't that explain why the water heater does not heat whereas the Red Dot does.
Charles
Last thought and it has to do with the process and accuracy of the temperature readings taken. Did you disconnect the outlet hose and collected a water sample and measured its temperature or did you use an indirect measuring device on the outlet line. If there is no flow the temperature difference could perhaps be attributed to that transferred through the metal while the volume of water inside the exchanger remains cool. I don't know exactly how the Red Dot heater is installed and if it would be an accurate indication that there is flow. The exchanger is made of aluminum and is adequate in size so the only other two variables are flow or temperatures. We are assuming we have continuous flow and a true outlet water temperature of 134 degrees. One of these two assumptions is wrong.
The factory Seaward WH made hot water in about an hour and was only replaced because it developed a leak. The Kuuma was installed EXACTLY the same way with the same hoses.
My Neighbor’s WH is hooked up to the thermostat bypass just like mine. The only difference is that he does not have a RedDot heater. Because the RedDot uses the coolant that has already gone through the WH this should not make any difference.
I have attached the FACTORY SCHEMATIC for the force10/Kuuma WH. Please note that the WH IS on a bypass circuit and NOT in the PRIMARY circuit. I confirmed with the Kuuma Tech rep that the bypass loop is how Kuuma prefers it to be plumbed because they do not want a restriction in the WH circuit to affect total engine cooling capacity.
I have no idea what you mean by horizontal and vertical layout but I will try adding some info to see if I can clarify. My WH came with a Temperature Control Valve (CTV) installed and I had always blamed it for the lack of performance. Last year I contacted the Kuuma tech department and they told me that the CTV’s have kind of gone out of fashion and I could remove it without causing any problem other than the potential for the water getting to scalding temperatures. Last year I removed it but got no performance increase. So you are correct, there is no temperature compensation control.
As far as vertical arrangement, as long as there is no air in the system (AIR LOCK), elevation does not mater from a fluid dynamic standpoint. The energy required to pump the water up is provided by the weight of the water coming down (basic siphon theory). http://en.wikipedia.org/wiki/Siphon The pump only provides flow, the lifting is done by siphon. Think of the siphons in the California aqueduct that take entire rivers over the coastal mountains. The fact that the RedDot produces plenty of heat with the coolant that is returning from the WH is proof that there is no air lock and the hot water is available.
Be that as It may, it does not pertain to my system. In my configuration the engine, the WH and the RedDot are all at about the same height. They are mounted under the settee and quarter berth.
Attachments
If your bypass valve is your engines t-stat, and the engine never gets to 160F in order to actually open it, your only flow is through the pin hole in the t-stat. ? Can you post a photo of where you are physically connected to your engine?
The temperature readings were taken using an infrared thermometer using the techniques given by Maine Sail on his "How To" article "engine temp monitoring & overheating baseline assessment." at the following website. http://www.marinehowto.com/ Great source of info, THANKS Maine Sail!!
I got the readings from the surface of the hoses because there was no metal in contact with the coolant. the readings were taken after continuous motoring so they should be close to correct but may be a bit low. the thermostat temperatures were taken from the metal casting as shown my Maine Sail.
I did not disconnect and take samples. it is antifreeze at scalding temperatures in a pressurized cooling system after all. The fresh water is easy to check directly. after an hour of running, cold water tap COLD, hot water tap COLD. I could tell no difference at all although the infrared show a 3º difference.
I did check the accuracy of the infrared thermometer by checking several know substances, boiling water, forehead etc. and they all indicated the correct temperature.
By vertical layout I mean the height of the water heater relative to the motor coolant reservoir.
Kumma manual mentions this:
"If you are using the heat exchange feature, locate the water heater as close to the
engine as possible. The heat exchanger port (or TCV inlet if equipped) must be
lower that the coolant output port of the engine.
Since your water heater is apparently above the motor coolant reservoir, why not call Kuuma and ask them why they require that the water heater vertical position must be below the reservoir.
Charles
Kumma manual mentions this:
"If you are using the heat exchange feature, locate the water heater as close to the
engine as possible. The heat exchanger port (or TCV inlet if equipped) must be
lower that the coolant output port of the engine.
Since your water heater is apparently above the motor coolant reservoir, why not call Kuuma and ask them why they require that the water heater vertical position must be below the reservoir.
Charles