Boiler and water heater connected together?

Old 07-31-18, 05:37 PM
Thread Starter
Join Date: Feb 2005
Location: Northern New Jersey
Posts: 458
Received 0 Votes on 0 Posts
Boiler and water heater connected together?

Getting familiar with the systems in my son's new house, I discovered that the boiler's water intake is a branch off the HOT line on the water heater. I have never seen this before and was wondering

(a) WHY?


It makes no sense to me.

Thanks in advance for the responses / education.

Old 07-31-18, 10:17 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Posts: 69,461
Received 2,802 Votes on 2,537 Posts
It had to go to the HOT water out side.
How could you possibly connect to the cold water side with all those couplers there.
At least they took the shortest route possible.

Good questions. Not a proper connection in my mind. If the water heater gets shut off for any reason..... the boiler water is off to. Not sure if hot water is good for the pressure regulator either.
Old 08-01-18, 01:48 AM
steve_gro's Avatar
Join Date: Jan 2004
Location: San Francisco
Posts: 1,092
Received 1 Vote on 1 Post
I haven't done that much work on boilers, but I have done some. The boiler shouldn't be taking make up water very often, and feeding it with hot may reduce any thermal shock.

I think it's OK -- seems preferable to feeding a hot boiler with cold water.

Thread Tools
Search this Thread
Ask a Question
Question Title:
Your question will be posted in: