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[trz]

Having an issue with hot water. It seems it's never real hot but it is hotter sometimes more than other times. I think when we don't use it real often then when we do use it it is not very hot. Wondering if it would be losing heat sitting in the water heater. Anyone have that happen?

    I have a Hawkin Energy 1100
Domestic cold water comes in, enters top side of 30 plate w-w heat exchanger exits bottom from there it enters cold side of water heater exits hot side then into mixer valve and on through the house.   Mixer is set at hottest setting.

Any thoughts?

[willieG]

in my opinion, you might as well leave power on to the hot water tank, it does not take much power to keep your water hot once there, the high cost of energy is to heat it from 50 degrees to your desired tempature there are other options but this is the easiest in my opinion as you are already plumbed up and running.

if you use very little hot water you could just bypass the hot water tank and use the plate exchanger to deliver "on demand"

add a small pump and circulate
add a thermo-syohon

[dukethebeagle]

get a sidearm

[mlappin]

When was the last time you cleaned the flat plate?

[RSI]

While the OWB is up to temp, turn on a hot water faucet and then feel how hot the pipe is going into the tank and also out of the tank into the mixing valve. If it is real hot going into the mix valve, that may be the problem.

If you have a gas water heater and it sits a lot between usage then it can cool down a lot. Natural vent water heaters are the worst.

Like mentioned above, you can add a recirc pump or sidearm.
Or if you have a humidifier, hook it up to hot water and it will keep the water heater hot.

[trz]

It's an electric water heater if that makes any difference.
     I'm not familiat with what a sidearm is i'll have to do some research.
 

    Actually i do use a fair amount of hot water but, it sits all night and in the morn its not very hot.

[RSI]

Electric don't lose much heat because they don't have a vent up the center.
You shouldn't need a sidearm though. Your setup should work fine.

If your 30 plate around 5x12 inches? Also if you do the test running hot water, also check the boiler pipe after the plate. If your pump is too small or the plate is getting plugged it will probably be fairly cold.

[braveblaster]

How is OWB plumbing (hot water) set up to get to the exchanger and DWH, and how is it plumbed from there?

[agriffinjd]

I have a 20 plate running into the top of the electric water heater and it works great.  I have my boiler set point at 190 degrees.  What's your at?  If it's too low that may explain it.

[Singlemalt]

I had a check valve in the top of my electric hot water tank that caused my hot water to be very hot, cold and or tepid.

Removed the check valve and no issues since.

[kommandokenny]

get a sidearm

Ditto,,,, I had no luck with the plate.
Or use them in tandem

[trz]

So, how do you clean a plates?
   Did the check with hot water running, pipes are not a whole lot of difference going into the tank, coming out of the tank or after the mixing valve. At least not what i can feel by hand!
    Checked the water in my tank with candy thermometer it read about 120. Checked the water from the boiler as soon as it enters the house it was about 142.
     Went out to the boiler and water temp gauge read about 170( cant't believe i'm losing 30 between boiler and house)!
   Looked at humidistat and through the little window set on 160, but i don't know what the differential is. How do i tell?

[trz]

Not humidistat, meant aquastat!

[RSI]

Check the temperature of the boiler pipe before and after the plate while running hot water. If the boiler water coming out of the plate is fairly low then you probably need a larger pump or remove some restrictions.

How did you check the boiler water temp in the house? If through the pipe, you should do the same at the OWB end.

What brand is your OWB?

[mlappin]

So, how do you clean a plates?
   Did the check with hot water running, pipes are not a whole lot of difference going into the tank, coming out of the tank or after the mixing valve. At least not what i can feel by hand!
    Checked the water in my tank with candy thermometer it read about 120. Checked the water from the boiler as soon as it enters the house it was about 142.
     Went out to the boiler and water temp gauge read about 170( cant't believe i'm losing 30 between boiler and house)!
   Looked at humidistat and through the little window set on 160, but i don't know what the differential is. How do i tell?

I use a short piece of garden hose wit two female ends, a five gallon bucket and a puddle pump with the garden hose adapter on it. Hook your garden hose to the flushing valves, the other end to the pump, place the pump in the bucket, add your cleaning solution ( i use white vinegar) then place another short hose from the other cleaning t into the bucket, then plug in the pump and let run.


Heres a picture from my setup.