No, you need to control the temperature of the water.
How do you do that?
No, you need to control the temperature of the water.
Because Marine water systems all rely on an on board pump for pressure (if not connected to shore water), I believe you'll find that check valves are a mandatory component of every pump to avoid bleeding pressure back into the storage tank, and can't/shouldn't be fiddled with. A hot water rated expansion tank on the output side of the water heater, or a cold temp rated tank on the inlet side makes living with pressure/temp relief valves a bit easier.
No, the check valve in the pump prevents pressurized water flow back into the storage tank/suction line. Without an inlet check, the pump would constantly cycle. The check on the water heater cold inlet is solely to prevent backflow of heated water into the cold piping. Creating a bleed path WILL NOT defeat its intended purpose, nor will it have any detrimental effect otherwise. I would not suggest doing it if that were the case.
I agree; the reason I tested it is because it says right on it 'test annually'
I believe that is exactly what I wrote. Quoth I..."I believe you'll find that check valves are a mandatory component of every pump to avoid bleeding pressure back into the storage tank, and can't/shouldn't be fiddled with."
Your recommendation that you drill holes in a check valve associated with the water heater kind of begs the question of how that accomplishes anything if the check valve in the pump is preventing a backflow of water through the cold water line? Further, I probably missed it, but water heaters don't come with check valves in the first place, although they can certainly be installed. Once installed, any cold water expansion tank might be isolated, which is why a rated hot water expansion tank on the hot water side is the preferred solution. https://www.plumbingsupplynow.com/plumbing/expansion-tanks/extrol/ex-30-extrol-inline-boiler-system-expansion-tank-4-4-gal-ex-30?utm_source=bing&utm_medium=cpc&utm_campaign=**LP%20Bing%20Shopping%20All%20Products&utm_term=4574861726366155&utm_content=Catch%20All
To make it a bit more muddy, some folks confusingly refer to the TP relief valve as a check valve. Go figure. https://www.reference.com/home-garden/check-valve-water-heater-ed922c7880e2a195
And for what it's worth, plumbers on hot water check valves....https://www.plbg.com/forum/read.php?1,231398
Evidently, I didn't make my point clearly. I did refer to the check on the water heater, its sole purpose is to prevent hot water from backing into the cold supply. It's independent of the pump and has no function in preventing the pressurized water from backing into the suction line of the pump or the storage tank. That is the function of the check on the pump, and without it the pump will cycle. Two different check valves, two entirely different functions. What did I miss?
Quite right. I had that model on the brain since I just installed one in my hydronic system. That said, most all potable water expansion tanks I've seen are all rated for 150 psi and 200 degrees anyway and are protected by the TP relief valve, so if you do feel compelled to install a check valve, rather than drilling holes in it, installing the tank on the hot water side would seem to make sense.The link you provided is for an Extrol EX-30. It's a thermal expansion tank designed for use in hydronic systems, not potable water. Entirely different tank than the thermal expansion tanks for use on pressure water systems (ST series). The Extrol 30 will tolerate 190F water in use on a hydronic system, but pressures there are <15psi. And it's a closed system, so the water in that system is inert for all intents and purposes. The EX-30 wouldn't last on a water heater application; that's not what it's designed for.
True. Until you install a likely unneeded check valve (on a closed marine system) that would prevent it from working.The preferred solution for a water heater application is a thermal expansion ST tank on the cold side of the supply piping.
True enough. There is sufficient bad advice on the Internet to go around.Regarding the link to whatever idiot wrote the drivel on check valves on water heaters being a safety device, it IS the internet. That makes it true, not??
How do you do that?