Warming water heater from engine...distance?

zane

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Jan 11, 2006
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19940
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Is there a maximum distance when running engine coolant to heat a water heater? I am in the midst of replacing elbows/risers and cleaning out heat exchanger. Figured good time time to make the connection. Neither the crusader manual or the water heater instructions mentions distance.
 
Shouldn't be enough heat loss to make a difference with a 34 foot boat. If there was, I guess you could insulate the hose going to the heater.
Jim
 
+1

Heat loss thru the proper hose will be minimal.
Keep in mind that the water in the tank will VERY hot compared to running on A/C.
I re-routed the heater hoses and there is ~16ft total run (8 out/8 back) with no issues

John
 
I should have worded my question better. i haven't measured yet but it's about a 10 foot run from the engine to the water heater. Is that too great a distance for the circulator pump to properly move the the coolant? Thanks for the responses.
 
no facts but I think you will be OK. If it is too far it will just reduce the flow for slower heat up but I doubt that will be noticable. Expect slower warm up on that engine. As above the coolant temp is too hot anyway so some heat loss wont matter.
Besides what choice do you have??
 
Zane, I had about a 14 foot round trip from my port engine to the hot water heater in my Mainship 40SB.
This might be a no brain'er use the proper hose rated for the task.
The port engine's circulation pump seemed to handle it with ease.
If you're that concerned after installing the hot water heaters engine heat-exchanger just monitor that engines temperatures.
I think you should be okay, make sure there are no sharp bends that can cause the hoses to kink over time or when they come up to temperature.
Best,
Bill
 
13 feet one way. Be careful. Water can be a LOT hotter than normal when heated by the engine vs electric.
 
quote:

Originally posted by OLD HOUSEBOATER

13 feet one way. Be careful. Water can be a LOT hotter than normal when heated by the engine vs electric.






Amen to that!!

I have a mixing valve (see link) on my boat heater. No scalding, quicker recovery and more "usage" from the same amount of water by keeping it hot, but not scalding hot.

LINK
 
Yes Bill, my concern is the motor plumbed to the water heater will overheat if the distance is too great and the circulator pump can't do the job.

Thanks for all the responses.
 
quote:

Originally posted by zane






since the hose to/from the heater will be exposed to high temp and potentially higher pressure when the engine shuts down, IMHO, its worth a few $ to purchase better quality hose. I went to the local hydraulic supply Co. and found some. in my application its a PITA to get to hose to inspect it fully for expansion/cracks etc.
 
My concern is this is just a waste of time....I have had both...Plumbed and un plumbed water heaters. I'm unplumbed now. The water in there stays hot for a long time. If I'm on the hook, I need to start the genset every so often any way.... I just re heat it then...

Plus it's easier to winterize too.... Just my two cents worth..... Thanks...
 
My water heater sits about 2' away from the engine, but, the coolant lines run to the front of the boat first for a heater in the cabin and then to the water heater and back to the engine. I have the stock water pump on the engine, fresh water cooled. Just a guess it is probably a 30' run from supply to return, factory set up...........D........
 
My Genny took a crap a couple years ago and I just removed it last year. Thing was huge 4 cylinder Kohler. The amount of time I anchor doesn't necessitate a new genset. We do anchor overnight a few times a year and I want the hot water for those times. Thanks all. I bought hose and fittings. We are going to Europe Thursday and I'll finish the plumbing when we get back.
 
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