2017 Cedar Creek Cottage 40CCK - Why would I not have hot water coming through my lines into the faucets?

SOURCE: Water is either hot or cold - no in between.

I found a way to get warm water in the shower, but I'm not sure it qualifies as a solution. After trying everything else I thought that maybe when I was feathering the faucet in the shower toward the cold side so I would get warm water that at a certain point it blocked the flow on the hot water side enough so that the sensor in the hot water heater sensed there was no demand in the line and it shut the water heater off. To test this, I went to the kitchen and turned the kitchen sink faucet all the way to the hot side and then turned it on so that I got a small flow of water. I waited for the water to get hot to be sure the hot water heater was working. Once it was hot, I left it running to keep demand in the line and then I went to the shower and turned the faucet on. When the water got hot I started feathering the control towards the cold side and soon I had warm water. So I think I'm right in that the sensor in the hot water heater was shutting the water heater off when the demand in the shower was lowered to a certain point when I was trying to adjust the water temp in the shower.

So now I can get warm water, but it means I have to leave the hot water running at another fixture in the house to create a false demand in the system so the hot water heater doesn't shut down. Is there a way to adjust the senor in the hot water heater so that it will stay on when I'm using the shower only, so I don't have to waste water by running another faucet when I want to take a shower?

SOURCE: Vaillant Mag 325 warm water only full pres. cold low pressure

you need a certain amount of water pressure for the water heater to turn on this is actaully one of the biggest problems that all manifactures forgot to tell anyone it is normal for the computer to shut down beings it is designed to heat water at a fast rate when you turn the water down, it's not enough pressure for for sensors to turn on to heat the water so turn on the spigot a little more and enjoy

SOURCE: warm water only

You can eliminate the shower control knob possibility by turning on your hot water anywhere else in the house. If you get hot water in other places, then it could be the knob causing it. A substantial lime buildup in the tank can also cause poor heat transfer from the elements to the water.

Allen Neal

• 359 Answers
• Posted on Dec 31, 2009

SOURCE: I have a Reliance 501 gas hot water heater that

hook up garden hose to faucet @ the bottom of the tank and drain the hose to the outdoors or down a floor drain and open the valve , leaving the cold supply valve on , let it run until it runs clear , this will get rid of some of the sediment deposit that form at the bottom of tank , is the most effective way i know , good luck

SOURCE: I have a problem with my Rinnai hot water heater

We had the same problem - the hot water would only be hot for 3 -5 minutes and shut off, then we had to turn the water off, wait a few minutes, and do it again. VERY FRUSTRATING.

Solution: The Rinnai serviceman showed me the heat-exchanger blower/fan: It was clogged with dust and moths.

Another clue: Our Rinnai was extremely noisy when the heat came on. After the fan was cleaned and replaced, it is nearly silent.

If you are reasonably mechanically inclined:
TURN THE BREAKER / POWER OFF to the unit.

The blower-fan is located in the lower central area of the unit (at least on our unit). If you draw imaginary north-south, east-west lines through the center of the unit, the fan is in the lower-left quadrant. There is a spring clamp securing the black rubber accordian-like tube to the fan. There are two screws that secure the fan to the unit. there are two plugs that connect to the fan, as well as a third air-flow sensor that should be removed. then you can look at the fan unit, as well as the grill on the underside of the heat-exchanger that should be cleaned.

My thought was to go out and get a simple bug-screen, and place it over the air-input outlet vent going outside, but the repair guy said that although it may sound good, if that screen ever gets clogged, or reduces airflow to the Rinnai, then the unit will work harder, or even shut off, giving the same problem.