Help - Very low pressure in hot water

Rev Roy · 11-01-2013, 01:34 PM

Woke up this morning to almost no pressure in all the hot water faucets. Just a trickle. The water is still hot. Cold water faucets are working as normal.

No sign of a leak. I'm plugged into a 1,200 gal water tank here on the ranch and the pump is working fine. Pump isn't coming on like I would expect if it was trying to make up pressure for an undetected leak.

Last night the temp was only in the low 40s, so nothing is frozen.

What could be effecting pressure just in the hot water?

Ideas?

Witch Doctor · 11-01-2013, 02:00 PM

Is your 1200 gal water tank hooked up to the city water connection? Have you tried to use the pump with just the unit storage tank only? Taking off the 1200 gal connection. The city water will by-pass the 12volt pump. then it only works on the 1200 gal pressure. to fill the water heater and such. It sounds like you are not getting water into the heater.

jtstromsburg · 11-01-2013, 02:09 PM

Possibly a bad check valve on the supply line out of the water heater. If it's stuck shut, you'd only get a trickle and then possibly nothing at all.

Rev Roy · 11-01-2013, 03:43 PM

Quote:

Originally Posted by gljurczyk

Is your 1200 gal water tank hooked up to the city water connection? Have you tried to use the pump with just the unit storage tank only? Taking off the 1200 gal connection. The city water will by-pass the 12volt pump. then it only works on the 1200 gal pressure. to fill the water heater and such. It sounds like you are not getting water into the heater.

My water supply has no city hook up. The water for my 1200 gal tank is trucked into my ranch on an as needed basis.

I must be getting water to the water heater otherwise I wouldn't be getting even this trickle of hot water from the faucets, right? I'm thinking the problem is somewhere after the water leaves the heater and before it heads to individual faucets...

Rev Roy · 11-01-2013, 03:49 PM

Quote:

Originally Posted by jtstromsburg

Possibly a bad check valve on the supply line out of the water heater. If it's stuck shut, you'd only get a trickle and then possibly nothing at all.

Sounds like a good possibility since it seems like the problem has to happen right out of the heater to effect every faucet the same.

I'm a newbie at all this. How does the check valve function and what would cause it to suddenly get stuck closed? And where is it in this system?

jtstromsburg · 11-01-2013, 04:00 PM

If you have a single valve bypass system, it would be right there at the output side (hot) of the water heater. If that picture is your heater, it's different than what I am thinking of though. If you turn water pressure off, and drain the hot water heater, you should be able to loosen the lines and see if there is a check on either or both. The check valves are a cheap thing to try at least

Witch Doctor · 11-01-2013, 04:23 PM

Quote:

Originally Posted by Rev Roy

My water supply has no city hook up. The water for my 1200 gal tank is trucked into my ranch on an as needed basis.

I must be getting water to the water heater otherwise I wouldn't be getting even this trickle of hot water from the faucets, right? I'm thinking the problem is somewhere after the water leaves the heater and before it heads to individual faucets...

I do understand that, but your tank was supplying water to the connection that says city water with a hose or you would have to be on tank water from your holding tank and then you pump would be involved, other then that the water pressure either from a tank or city water creates the pressure in the system. It is either one or the other. I know of no check valve in the system after the hot water heater.... Good luck. If your trailer tank is full try just the waterpump and see if that works. That would feed the hot water tank and the cold water side then. You can also open your releaf valve and see if you get any hot water out, just do not get BURNED doing it.

Rev Roy · 11-01-2013, 04:30 PM

Quote:

Originally Posted by gljurczyk

I do understand that, but your tank was supplying water to the connection that says city water with a hose or you would have to be on tank water from your holding tank and then you pump would be involved, other then that the water pressure either from a tank or city water creates the pressure in the system. It is either one or the other. I know of no check valve in the system after the hot water heater.... Good luck. If your trailer tank is full try just the waterpump and see if that works. That would feed the hot water tank and the cold water side then. You can also open your releaf valve and see if you get any hot water out, just do not get BURNED doing it.

Gotcha. Thanks!

Witch Doctor · 11-01-2013, 05:19 PM

Quote:

Originally Posted by Rev Roy

Gotcha. Thanks!

Are you really a REV? Or is that just a nickname?

OldCoot · 11-01-2013, 05:28 PM

Quote:

Originally Posted by Rev Roy

Gotcha. Thanks!

I would shut the water off, drain the water heater and disconnect all hot water lines to inspect for debris. While you have the water heater empty, check the anode. I suspect it to be gone and the debris in your lines.

Rev Roy · 11-01-2013, 05:29 PM

Quote:

Originally Posted by gljurczyk

Are you really a REV? Or is that just a nickname?

Yep. I'm a real Rev.

Rev Roy · 11-01-2013, 06:32 PM

Quote:

Originally Posted by jtstromsburg

Possibly a bad check valve on the supply line out of the water heater. If it's stuck shut, you'd only get a trickle and then possibly nothing at all.

You were right. It's the check valve. Can I just remove it or do I need to replace it? What's its purpose?

jtstromsburg · 11-01-2013, 07:24 PM

You'll want to replace it. Without it, the wh would be much less efficient as cool water would seep back in. Also, it is needed for winterizing proposes.

Rev Roy · 11-01-2013, 08:05 PM

Quote:

Originally Posted by jtstromsburg

You'll want to replace it. Without it, the wh would be much less efficient as cool water would seep back in. Also, it is needed for winterizing proposes.

Got it. Thanks.

**Herk7769** · 11-01-2013, 09:02 PM

Quote:

Originally Posted by Rev Roy

Sounds like a good possibility since it seems like the problem has to happen right out of the heater to effect every faucet the same.

I'm a newbie at all this. How does the check valve function and what would cause it to suddenly get stuck closed? And where is it in this system?

If that photo is of your tank, it appears you have a 3 valve system (not a one valve) and I can only see the lower cold water on/off valve in your photo.

There should also be a valve in the vertical blue pipe and another (the hot water) valve in the horizontal red pipe.

My money is on the valve in the red pipe not being open very much. The handle should be aligned with the pipe like in this photo.

cci · 11-01-2013, 10:12 PM

I belive start simple first. Any chane your hot water bypass has been has been turned by accident. Both getting pressure from same place so could also be a kinked or blocked line. Would have to be right after water heater or not all faucets would trickle at same time.

**Herk7769** · 11-02-2013, 01:30 PM

Quote:

Originally Posted by cci

I belive start simple first. Any chane your hot water bypass has been has been turned by accident. Both getting pressure from same place so could also be a kinked or blocked line. Would have to be right after water heater or not all faucets would trickle at same time.

I believe that if the bypass valve were open, the pressure and flow would be identical; just the cold water would mix with the hot and the result would be plenty of luke warm water.

Several issues of luke warm water solved by closing that valve.

It could also be a rare (but not unique) 2 valve system where there is a check valve at the hot water outlet AND a bypass valve. In that case the check valve should be replaced.

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