converting to pumping away/ cost effective?

STEAM DOCTOR

Just a little intro. I have no training in hydronics. The extent of my hydronic education is from reading Dan's books. I was by a customer recently and while pocking around his basement I noticed that his hot water boiler has no air eliminator, a circulator on the return and an interesting compression tank set up. There are two pipes coming from the top of the boiler. One pipe is the main. The second pipe has the compression tank and water feed connected to it. If I understand this correctly this is the equivalent of placing the point of no pressure change in middle of the boiler. My question is if it is cost effective for the customer to move the circulator to supply, move the tank to the supply main between the boiler and circulator and to add an air eliminator. I am also interested in knowing which air eliminator  the knowledgeable wallies would recommend. The boiler is a40k unit with one zone on a small addition to the house. The customer complains of cold and of always hearing water running. I have thoroughly read pumping away. GREAT BOOK!  Thanks a ton.

Mike Kusiak_2

What boiler and what type of tank?

Is the compression tank a plain steel tank or a bladder tank? Some boilers such as the Burnham series 2 have a built in air separator in the heat exchanger casting, which is connected to a tapping in the top of your boiler. If a plain steel tank is piped into this top port it will serve to return air to the tank and prevent waterlogging. Of course, the air elimination will work much better if pumping away from the boiler, but even with the pump on the return the built in air separator is pretty effective.

STEAM DOCTOR

dont remember

Thanks for the reply. I don't remember which boiler. The tank is a diaphragm type.

Ironman

This Setup...

Won't work with a bladder tank since there is now no means of air removal. Someone probably replaced an old bladder-less tank without realizing they'd defeated the air elimination system.

You must use an air separator with a bladder tank.



If you've read Dan's books, you've gotten alot of hydronics education.

STEAM DOCTOR

adding air eliminator

is adding the air eliminator adequate or should i also move the circulator and tank?

Mike Kusiak_2

Air vent

You can first try attaching an automatic air vent to the top of the riser from the boiler where the tank is connected. The air that is now collected at the top of the boiler will now be vented.



Do you really have an air problem or is it something else. What type of noise is the costumer hearing. Is it velocity noise or gurgling from trapped air?

STEAM DOCTOR

running water

The customer describes the noise as a running water noise.