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Topic: Aquahot 100-01 cant keep hot water (Read 668 times) previous topic - next topic

Aquahot 100-01 cant keep hot water

Already changed the mixing valve at the shower first and fixed the problem originally..

Now I have changed the mixing valve on the aquahot, CHanged all the coolant with ELC red to match the motor

Cleaned =and flushed the water to descale before swapping parts..

Whats next? Seems it gets the hot water from the tank then its out.. is there another mixing pump ? I have an extra new one I can replace one if needed..

Ideas..

2 min shower with hot then its cool water.. seems the heater was cool also.

Re: Aquahot 100-01 cant keep hot water

Reply #1 –
Probably need Rudy on this one. Do the heaters work? Did you buy a new AH mixing valve and just use the guts out of it for the installed valve? Did you adjust the mixing valve after installing?
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Aquahot 100-01 cant keep hot water

Reply #2 –
David,  Any time the burner is running, so should be pump 2 stiring the coolant in the tank.  Pump 2 is energized during burner operation by the red diode wire coming out of the harness to the burner running over to the pump connection on the middle clear relay.  The pump connection on the relay is the lower rear (pump side) connection.  The top connection is for the fans inside.

So start the burner and see if pump 2 is running.  The pex pipe above the pump will be hot is it is pumping fluid.

The pump is magnetically connected so it can run and not be pumping.  If this is true, the pex will not be hot.
Rudy Legett
2003 U320 4010 ISM 450 hp
2001 U320 4220 ISM 450 hp
1995 U320 M11 400 hp
1990 Granvilla 300 hp 3208T
Aqua Hot Service Houston and Southeast Texas

Re: Aquahot 100-01 cant keep hot water

Reply #3 –
Quote from: Rudy –
David,  Any time the burner is running, so should be pump 2 stiring the coolant in the tank.  Pump 2 is energized during burner operation by the red diode wire coming out of the harness to the burner running over to the pump connection on the middle clear relay.  The pump connection on the relay is the lower rear (pump side) connection.  The top connection is for the fans inside.

So start the burner and see if pump 2 is running.  The pex pipe above the pump will be hot is it is pumping fluid.

The pump is magnetically connected so it can run and not be pumping.  If this is true, the pex will not be hot.
Thanks Rudy .. will give it a check in the next few days.. Appreciate it.

If it is not running what would be next? Relay? Diode? Pump? basically in that order?

Re: Aquahot 100-01 cant keep hot water

Reply #4 –
Well David,  The red diode wire needs to show battery power at the relay connection.  If so, the pump is probably bad.  Flow the power and where it stops is the problem.

The power from the burner to the pump is connected at the relay.  The relay has no part of the stirring operation.  The relay energizes the pump when the bathroom thermostat calls for heat latching the relay to start the pump 2 and the bathroom fan.

Another check is "Do you have heat in the bathroom with the bathroom thermostat turned up and bathroom fan blowing air?"  If so, the pump is fine.

Then, with the burner running, is the diode wire energized at the relay connection to the pump.  VOM meter will answer that.

If you wish to call me while trouble shooting, I am available 8 to 8 central at 7 one 3  8 one 8  3234
Rudy Legett
2003 U320 4010 ISM 450 hp
2001 U320 4220 ISM 450 hp
1995 U320 M11 400 hp
1990 Granvilla 300 hp 3208T
Aqua Hot Service Houston and Southeast Texas

Re: Aquahot 100-01 cant keep hot water

Reply #5 –
Heater is working in the bath for sure as I used it this weekend.. I will run through and call if I get stumped (sorry stump I couldnt resist)..  :))

Re: Aquahot 100-01 cant keep hot water

Reply #6 –
With pump verified, bet this is a cheap fix.  Let me know what you find.
Rudy Legett
2003 U320 4010 ISM 450 hp
2001 U320 4220 ISM 450 hp
1995 U320 M11 400 hp
1990 Granvilla 300 hp 3208T
Aqua Hot Service Houston and Southeast Texas

Re: Aquahot 100-01 cant keep hot water

Reply #7 –
Are you heating near-freezing outside water or fresh tank water? 
Tom Lang K6PG (originally  KC6UEC)
and Diane Lang
2003 38 U295 build 6209
2016 Jeep Grand Cherokee Summit Ecodiesel
still have tow-ready 2006 Acura MDX 
Temple City, California
Motorcade 16681 California Chapter President
SKP 16663 member of SKP Park of the Sierra, Coarsegold California
FMCA F071251
Retired electrical and electronic engineer

Re: Aquahot 100-01 cant keep hot water

Reply #8 –
What gpm is your shower head flowing?
Regards,
Brett

'99 42' Foretravel Xtreme
'14 Brown Motorsports Stacker
'05 Chevy SSR
'02 BMW R1150R

Re: Aquahot 100-01 cant keep hot water

Reply #9 –
Quote from: Tom Lang –
Are you heating near-freezing outside water or fresh tank water?
No 55 degrees at my house and the heater in the basement was on.

Shower head is a water saver head with the air hole for mixing and seeming like it has a high pressure but with a low volume..