Hot water pressure please.....

[NYSail]

So this deals with water pressure from hot water heater.
On old boat had a new fresh water pump (can't remember gpm.... maybe 3.5) and raritan 6 gallon hw heater. Pressure out of tank, hot or not was always very strong especially when hot.
New boat have a sureflow 3.8 gpm pump and Seaward 11 gallon tank tank. Water trickles..... hot or cold.
Both heaters were ac as well as engine heated. And btw cold water in new boat comes out just fine similar to old boat.
So what gives.... do I need a higher pressure pump? Hw heater not building enough pressure......
Thanks

 

[Davidasailor26]

If the cold water side has plenty of pressure then the problem isn't the pump. My guess is that there's a clog somewhere in the hot line either into or out of the heater. Good places to start checking would be if you have a check valve and/or gate valve going into the heater, or a mixing valve on the way out.

 

[NYSail]

Thanks..... yes already checked. Straight out of tank, no gate valves or mixing valves. Though it does come out of hw heater into a manifold..... could have a blockage and will take apart and inspect.
Thanks!

 

[cymeyer]

NYSail,
Did you check the pressure relief valve on the hot water tank or the drain valve on the back? If either one is open (opened when draining for winterizing or whatever), you won't be able to pump hot water.

 

[NYSail]

NYSail,
Did you check the pressure relief valve on the hot water tank or the drain valve on the back? If either one is open (opened when draining for winterizing or whatever), you won't be able to pump hot water.

Pressure relief appears to be ok..... no leaking. And drain valve in front the front of heater is closed. Get no cycling of pump.

 

[cymeyer]

Are you sure there is water in the hot water tank? You can open the drain and the pressure relief valve and see if it drains out. If not, then you know better where to look. Wonder if there could be a shut off valve going into the tank to keep anti-freeze out when winterizing?

 

[NYSail]

I have hot water.... just that pressure is horrible. When I turn on hot water, the pump runs...

 

[NYSail]

So these fittings into and out of the tank may be the problem...... nice looking but small diameter in and out obviously restricting flow.

 

[Davidasailor26]

When you first turn on the hot water is there good pressure that then drops off, or is is poor from the start? If the pressure starts off ok then the problem is likely farther from the faucet, maybe on the tank intake. If it's poor from the start then the problem is likely closer to the faucet. Also, I presume the problem is the same on multiple faucets?

 

[NYSail]

From all faucets runs with minimal flow..... it's like no pressure is being built up in tank.

 

[Davidasailor26]

That helps narrow it down a little. If there were a blockage on the way into the tank it would still build up pressure eventually when the faucets are closed. The pressure would then start strong when you open the faucets and die off. Since the pressure is consistently low my guess is that it's a problem somehwere on the output side of the tank or the plumbing after. My next thing to check would be to turn off the pump, let the pressure drain from the faucets, then take the output hose off the tank. Turn the pump on and see whether you have a trickle or a stream there.

 

[cymeyer]

Did you check the aerator of the faucet? What about the bathroom water pressure? Same issue?

 

[Benny17441]

Good pressure cold side, poor pressure hot side in all faucets; I would say you have an obstruction in the water heater itself. To test by-pass to the water heater and see how the pressure is in the line. If it is the tank I would consult with the manufacturer about any know causes and recommendations they may have.

 

[NYSail]

I am looking at those fitting leading to and from tank for hat reduce flow.... (picture above) they may be the problem. I figure I will get new with larger flow.... sure the tank has some internal calcification as it is 12 years old.