Insulating Coolant/Exhaust hoses

My cockpit locker gets pretty hot in the summer from the exhaust hose and hot water heater hoses as well as the expansion tank. I was thinking of insulating the hoses to keep the heat down as this heat tends to make its way over to the aft cabin too. Also the fridge compressor is in this locker and ends up sucking in hot air which cant be that effeicient. Maybe some sort of pipe insulation, but something that will handle a marine environment. Any thoughts?

I'd also look at increasing the ventilation through that bilge area. Might be an easier/more effective way to keep it cool. Do you have cowls on the stern or cockpit coaming that can be faced in opposite directions?

Cowl vents run hoses to engine compartment via a blower currently. Not sure how I would ventilate the locker. Its the under the starboard cockpit seat, not the aft one.

I put sidewall vents(2-4"x6") as high as possible in my cockpit locker to
solve this problem. My refrigeration compressor is also located in the
cockpit locker and it works great, plus keeps the noise out of the cabin.
Good luck on your HOTSEAT !

Oh yeah... the insulation. Closed Cell plumbing insulation will work here.
Has to be protected from chafing. Use alluminum tape at the joints.
As long as you keep this stuff out of the SUN it will last forever and
can't ABSORB MOISTURE. They also make a PVC jacket for this product
that can be used to to prevent chafing. Sheet is also available for your
water heater. Purchase the GOOD STUFF at a industrial HVAC/Plumbing
Supplier. The quality will be better and heat rating will be higher than
the products available at the Hardware Store. We use this insulation
on heating piping in HVAC that runs at 180-200F.

Warmth...

I also used Dan's insulation idea for the longer hose runs from the engine to the water tank internal heat exchanger and thence a few feet further to the little cabin heater coil-and-fan. I was "losing" too much heat as the hot hoses passed under the head counter and thru the aft hanging locker on their way. When the engine is under load it still produces mucho heat for the cabin, and we never use the "high" setting for the fan speed. Even the amount of heat getting out now keeps that aft locker nice and warm and dries off the foulies very well.

As mentioned previously, there is a surprising amount of "waste heat" available from a little one liter three-cylinder diesel!

Loren
Olson 34
Universal M25XP