Threads on hot water tank connections

Willhound

Does anyone know offhand if the threaded fittings on the lines to the hot water tank on a 2000 FV270 are NPT or compression thread?
Reason I ask is that I'm going to wnterize my water system next weekend and my mechanic suggested a quick and easy way I like. He emphatically stated " whatever the #@$@ you do, do NOT put pink stuff in your water tank or heater." Stinks and serves no purpose. He suggests opening the drain on the hot water tank, pulling the two lines off, join them with a nipple, pull the feed line off the fresh water tank and stick it in a bottle of pink stuff. Run the antifreeze through the pump and all lines until it comes out of the various faucets/ showers and you're done. The little bit of residual water in the tanks will never cause damage because it's easier for the ice to expand into empty space than push against the tank. Guy has 30 years experience and I trust him.
So....I want to bring the right nipple to the boat on Saturday.
Differing opinions welcome....

Handymans342

NPT

Dream_Inn

I agree, but I go one step further and just use a water heater bypass.  This allows you to just turn a valve and it diverts the water heater.  You can also add a T with a switch (basically the same as the water heater) and turn it for the pump to use a hose instead of the tank.  What all this does, is it allows you to do the water system without removing hoses each year.

I agree with Handy, it is NPT.

Black_Diamond

Put the pink stuff in your water heater and it will take forever to get the nasty taste out.  Been there.  lol

reneechris14

I pulled the lines off the tank and used a 5/8 rubber heater hose about 12" long to connect the two to bypass the tank. I do have a city water connection that needs to be flushed though?

diggin2day1

This is the bypass kit... https://www.westmarine.com/buy/camco--water-heater-bypass-winterizing-kit--329195?recordNum=2

Liberty44140

Yea my bypass hose and hose clamps cost about $8 at lowes. Pull the line in and line out of the tank and connect them together with a hose. 2' x 5/8" Id should be right. Hose clamps. Now the heater is bypassed. Then drain the heater in to the bilge from the spigot on the heater. Done. 

J3ff

Shoot, I'm just realizing that to winterize I guess I have to hook the hot water hoses back up as there's probably fresh water just sitting in them. Grrr. 

randy56

@Willhound, that's a great idea, I'll take a picture for you tomorrow of Hot water heater, As I've brought her home for winterizing, always dumped pink in tank and ran through out, then in spring flushed 2/3 water tanks full of water, to refresh water heater and lines. It stinks, like rotten eggs. 
However my yoga/gymnastic/ contortion/ days are over, may not be able to maneuver, in there to take it apart.  we'll see. 

Willhound

diggin2day1 said:

This is the bypass kit... https://www.westmarine.com/buy/camco--water-heater-bypass-winterizing-kit--329195?recordNum=2

Looks interesting but I won't be able to get one in time. Could build it from the hardware store. That kit makes reference to (edit: sorry 3/4") threads which sounds odd considerng the lines are 1/2" OD Pex.. Are the threads not 1/2"?

randy56

Willhound

Thanks for the pic @randy56. I'm going to try and find parts to build something like this. In the meantime, I was thinking of just undoing the two knurled flanges at the end of the pex and sticking a nipple in there. I'm thinking 1/2"?

randy56

Working on winterizing myself this week also, Repaint outdrive, change gear lube in outdrive, engine oil and filter, dang oil filter was stuck, had to drive a big a$$ screw driver through it, to get it off. Ended up buying 16 gallons of pink stuff, spent the extra $1 per gallon and got the environmentally safe stuff. put 8 in water system, one for genny, after draining muffler,  5 gallons for engine. any left goes in holding tank. I use a turkey baster to suck all the water out of the shower pump basin. Fun fun fun. 

Handymans342

Why dont you have a HW bypass???

randy56

It's done now, Interesting find ? finding 100's of tiny mussels attached to outdrive trim tabs, ect, pressure washed off easy, Normally I run the engine 40 minutes on muffs, to warm up oil before changing it, makes it flow out better. When I removed the muffs, 20 or more had been forced out of the water inlet, into muffs, and surrounding outdrive.  These great creatures, are probably  in my water pump, what do you think? Those hard shells will eat it up.