What are these fittings on my water heater?

NYSail · Oct 30, 2018

What I call a P/O special!

Capt jgw · Oct 31, 2018

Never seen one like that but there should be a check valve on the input line. Keeps the hot water from backing up into the cold system. Maybe the black thing.

dlochner · Oct 31, 2018

Probably, or should be a check valve. As @Capt jgw says it keeps hot water from backing up into the cold water system.

While you're taking things apart to winterize, make life easier next year. Replace the hose barbed fittings with SS supply lines from the hardware store. These are the ones that connect faucets to the plumbing system.

capta · Oct 31, 2018

Though I have never seen one that looks like that, I'd also agree that it is a check valve.

Parsons · Oct 31, 2018

What I particularly like about the black piece is they have turned it so that the screws face the water heater, so it cannot be disassembled in-place. Just one more half-turn and the screws would be accessible. As @NYSail said, a gift from your PO.

Gunni · Oct 31, 2018

Saw it off and toss it.

LeslieTroyer · Oct 31, 2018

The black part I was told is a pressure regulator/check valve. I have one on my boat. Looks like the grey is the cold water input (high temp plastic??))

The pressure regulator/check valve is for when you hook up to shore water and is usually next to the input to the boat

Les

jssailem · Oct 31, 2018

Sure glad @LeslieTroyer someone who knows, stepped in. I was going to hazard a guess. Check valve was in the top 3 options. Not sure it is really needed. But then I have 100 gallons of cold water on the boat. Not sure the WH can significantly impact that volume through conduction. May reconsider when I go for the plumbing replacement project.

dlochner · Oct 31, 2018

jssailem said:
Sure glad @LeslieTroyer someone who knows, stepped in. I was going to hazard a guess. Check valve was in the top 3 options. Not sure it is really needed. But then I have 100 gallons of cold water on the boat. Not sure the WH can significantly impact that volume through conduction. May reconsider when I go for the plumbing replacement project.

When the water is heated through the engine heat exchanger it will reach the engine's operating temperature, or about 160*. That temperature is below the threshold for the pressure relief valve to blow but hot enough to generate some pressure due to expansion. W/out the check valve that pressure will force hot water backwards through the system to the water tank. When someone opens a cold water valve they may get a blast of scalding water out of the faucet. The check valve prevents that from happening.

Capt jgw · Oct 31, 2018

In a house the check valve is a building code requirement for just that reason.

jssailem · Nov 1, 2018

Well I understand that concept. I will need to examine my waterlines more carefully. There must be a check valve somewhere. But not visible to me. None of the symptoms mentioned. No scalding water in the cold line. Pressure pump not pressure from the mainline like a house.
Granted I have not had an issue with the water, yet. That is one of the systems that has always worked with no evidence of leaks. So the total refit plan for the plumbing system to new pex has a lower priority.

On the other hand, the new front hatch and the new alternator system have arrived and are high on the priority list for install. Thanks @mainesail the package arrive yesterday.

Stu Jackson · Nov 1, 2018

http://c34.org/bbs/index.php/topic,4114.msg23433.html#msg23433

tis indeed a check valve, see reply 3 in the link and look at page 2 for the replacement

What are these fittings on my water heater?

Ward H

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NYSail

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Capt jgw

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dlochner

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capta

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Parsons

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Gunni

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LeslieTroyer

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Ward H

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jssailem

SBO Weather and Forecasting Forum Jim & John

dlochner

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Capt jgw

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jssailem

SBO Weather and Forecasting Forum Jim & John

Ward H

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Stu Jackson

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Ward H

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