I have a thru hull, to a strainer, to a pump, to a hose with T connector valve (one leg to AC/Heat unit, one to open air). I shut off thru hull and poured antifreeze into open strainer but pump would not suck in anti freeze. Finally by opening T connector to open air it worked a little. Can any one explain easy way to prime pump, assuming that is problem? Thanks
Priming AC/heat pump.
- Thread starter Ted10028
- Start date
I’ve had similar problems priming mine for winterization. When the boat is in the water the water tries to seek its own level, above the pump, which helps hold a prime under normal operation. Trying to get that same amount of pressure just by pouring antifreeze into the strainer is tough. I’ve found the easiest way is to use a spare aquarium water change pump to help push antifreeze through the circuit. I put a funnel on the input of the pump and run its output into the AC intake hose.
Thanks, Do you find that primes the main pump so you can withdraw the aquarium pump? Also. don't you have to get rid of air in the line? My system has what appears to be an air bleed valve so that when I open it air and water come out which sometimes helps to pump to start pumping. Thanks again.
I haven’t found any way to keep enough antifreeze in the line to stay primed without the aquarium pump or a continuous way of pouring AF into circuit. Having two people does help get it done without the aquarium pump though. One person opens the bleed valve and turns on the AC. The other starts pouring AF down a funnel into the input line. The pump pulls the AF very slowly at first. Once a decent stream of AF comes out the bleed line that person closes the bleed valve. The other person keeps on pouring AF in the funnel ensuring it doesn’t run dry - if air gets in the line the whole process needs to be restarted.
With the aquarium pump I can do this all alone since that’s more tolerant of short lapses in AF supply. I turn on the AC and the pump and start pouring in AF with the bleed valve open. Shortly after that I can close the valve, go back to the funnel, and pour about 4 gallons of AF through my 16K BTU AC.
With the aquarium pump I can do this all alone since that’s more tolerant of short lapses in AF supply. I turn on the AC and the pump and start pouring in AF with the bleed valve open. Shortly after that I can close the valve, go back to the funnel, and pour about 4 gallons of AF through my 16K BTU AC.
thanks. wow 4 gallons seems like a lot.i have no idea how many gallons my ac/heat pump requires for 32' catalina. when spring comes do most people just pump all the antifreeze out into ocean?
The 4 gallons is probably overkill. The first couple are what I recover from my water heater after winterizing that, since I don’t have a bypass kit for it. Looking back at my notes from a few years ago before I reused the water heater AF it looks like I generally used 1.5 to 2.5 gallons of fresh PG.
Yes, I do just let the antifreeze get pumped overboard when winterizing and in the spring. Propylene Glycol is fairly non-toxic and biodegrades quite quickly. Ethylene Glycol (which I use for the engine winterization) is also as non-toxic to fish and as biodegradable in water (but certainly much more toxic to mammals, so should not be used for anything potable or where it could leak onto land).
Yes, I do just let the antifreeze get pumped overboard when winterizing and in the spring. Propylene Glycol is fairly non-toxic and biodegrades quite quickly. Ethylene Glycol (which I use for the engine winterization) is also as non-toxic to fish and as biodegradable in water (but certainly much more toxic to mammals, so should not be used for anything potable or where it could leak onto land).
I don't have a bypass kit for my hot water heater either. I simply run all hot and cold water lines dry then fill both water tanks with a couple gallons of antifreeze and then run all the hot and cold water lines again until pink antifreeze comes out. Does that make sense? thanks
That’s probably fine for the cold water side, but how do you ensure you’re not just diluting the water in the heater with the antifreeze? The hot water outlet is usually toward the top of the tank, so if you just run the pump until you get air out the hot water faucet there’s still probably a few gallons of water in the tank. It’s better to drain that water out the cold water inlet before letting AF back into the tank. Unfortunately without a bypass that means the heater has to get filled back up with several gallons of AF before anything starts going to the faucets again.