Community Forums

Mwig · 01-22-2022, 10:47 AM

2011 Anthem Aqua Hot 450D
When I use my floor heat the boiler fluid level drops dramatically. I assume it’s because there is air in lines due to the tubing having highs and lows throughout the floor. In the past, I added fluid to the tank bringing the level up to hot line when burner kicked off. Latter when not using the Aqua hot I find the expansion tank completely full and running out overflow tube.

My question, has anyone else experienced this? If so, how did you solve this?

I have a three quart tank 7” tall and Aqua Hot sells a five quart but it’s 13” tall.
It will mount in the same place but being five inches taller I would not be able to add fluid without a pump, syringe or something else to force fluid in.

Any thoughts or advice?

J Gunter · 01-22-2022, 12:51 PM

Quote:

Originally Posted by Mwig

2011 Anthem Aqua Hot 450D
When I use my floor heat the boiler fluid level drops dramatically. I assume it’s because there is air in lines due to the tubing having highs and lows throughout the floor. In the past, I added fluid to the tank bringing the level up to hot line when burner kicked off. Latter when not using the Aqua hot I find the expansion tank completely full and running out overflow tube.

My question, has anyone else experienced this? If so, how did you solve this?

I have a three quart tank 7” tall and Aqua Hot sells a five quart but it’s 13” tall.
It will mount in the same place but being five inches taller I would not be able to add fluid without a pump, syringe or something else to force fluid in.

Any thoughts or advice?

Sounds to me like one of your check valves sticking open allowing fluid to flow back into the tank when unit is off. When unit starts it pumps the fluid back into the lines dropping level in the tank. If you add fluid, when the unit shuts off fluid will leak back into tank causing it to overflow.

jmorse1 · 01-22-2022, 01:17 PM

I agree...sounds like the check valve for Zone 2 is stuck open. This check is located at the Zone 2 pump inside the Aquahot . Give the check valve a good rap with a screwdriver and see if that helps

HarleySG · 01-23-2022, 04:18 AM

Have you tried purging the air from the system via the air release valve on top of the AH?

Mwig · 01-23-2022, 05:49 AM

Thank you, I will check the check valves. I have bled air from unit also.

alank · 01-23-2022, 04:30 PM

Was just looking at an Aqua Hot manual today and on about page 110 are instruction about draining and refilling the Aqua Hot, including purging the air out of the system. You might have a look at those instructions.