H37C Plumbing

[Ed Schenck]

I discovered when trying to winterize that something has happened to my hot water pressure. We ran the tanks dry on our last outing of the season. Then we returned to the marina in very rough conditions. I did not try the hot water until I bypassed the tank and then tried to pump anti-freeze through the system. No problem with the cold.I disconnected the bypass and put the cold water hose in a bucket. No problem pumping anti-freeze into the bucket. I tried blowing into the hot water hose with the galley faucet open. Might have heard a little gurgle. With the pump running and any one of the three hot water faucets open I get just a trickle. I did manage to get all pink flowing from all three faucets.With the rough lake crossing is it possible the hose got pinched somewhere? Since all three faucets are affected I think the "clog" would have to be before(or at) the first 'T'. I have the big plumbing diagram and it looks like the black hot water hose comes out of the tank, across the fuel tank, and then T's behind the liner by the end of the nav station. Anyone ever seen or gotten their hands on those T's? Any other ideas?

 

[Josh]

hey Ed

Could you try by-passing the H2O heater by connecting the hose going into the heater and the hose coming out (with a plastic connector--are the hoses the same size?, you might need a step-down connector). I think that would be easier and you could establish that the problem is not with the intake or output at the heater. Talk to you soonJosh

 

[Peggie Hall HeadMistress]

I don't think you have a problem

The water heater discharge is at the top...it's automatically kept full by your water pump. However, your water tank is empty...so once the level in the water heater drops below the top of the discharge fitting, you're not gonna get any hot water. If you've bypassed it, you won't get any even if the tank is full. Reconnect your plumbing bypass...drain your water heater via the petcock at the bottom of it...either suck the rest of the water out of it and call it done or add enough antifreeze to the tank for the amount of water left in the water heat...and I THINK you'll find that everything will be fine after you've reconnected the water heater to the plumbing and refilled the water tank next spring.

 

[Ed Schenck]

Misunderstood?

I probably rambled too much in the original post. The hot water tank is winterized and bypassed. My only problem is lack of water pressure at any of the three hot water faucets.All that I have proved is that the pressure is good at the hot water tank. In other words I disconnected the bypass and had good pressure from the hose that connects to the tank inlet, the cold water source.I reconnect the bypass and turn on any or all hot water faucets and only get a trickle. The "bypass" is nothing more than a 5/8" nipple with the two hoses clamped to it. If I turn on any or all cold water faucets I have normal flow from those.The entire system worked fine until the tanks went dry during a rough Lake Erie crossing. That fact could be entirely misleading I suppose. But even so I was able to get the anti-freeze through the hot water plumbing albeit at a very slow rate.

 

[Seattle Scott]

Ed, I would suspect

a clog before a hose crimp. Maybe disconnect the tank bypass and affix a dingy foot pump to the hot/out hose from tank and open closest faucet (gally?) remove any spigot screen and jump on the foot pump. Or do in reverse and hook up shop vac to hot/out from tank and suck out any stuff from line while you open and close each of the hot side faucets. Probably better to pull out the junk with a vac rather than try to push the junk through with a foot pump in case the latter only makes things worse.

 

[Ed Schenck]

Scott, good idea!

I really like your shop vac idea Scott. I always take an old vac to the boat for the winter projects anyway. Just have to get a good seal between the vac hose and the water line. Then, of course, I have to put the anti-freeze back in there.An aside about the anti-freeze. I have read numerous times on HOW about simply blowing the water out of the water lines. That leaves almost empty hoses with lots of moisture and opportunity for stuff to grow in there. Much better to fill those lines with pink stuff.

 

[Don]

Comment from PNG

EdLet me add a comment. I have a H37C At Whidbey Island but I am currently on a consulting project in Papua New Guinea. I have changed the hot water tank twice in my Hunter and my immediate thought when reading this question was the one way or non return valve in the feed line to the hot water tank. My has "locked" closed a couple of times when I ran the tanks dry.I would remove the non return valve and clean it.When the tank runs low the heat and pressure increase forcing the non return valve to seat very tightly. It probably is seated into the normal crud in the line and needs a good bang to loosen it.Fair winds.Don