Size of Supply Pipes for Radiators

CapeCoaler · Post by **CapeCoaler** » Wed. Nov. 04, 2009 3:29 pm

Charge them a fair service call...
Then when they do have a real problem that takes a bit of time...
You will be guilt free for charging them appropriately...

Sting · Post by **Sting** » Wed. Nov. 04, 2009 3:45 pm

even back in the day -- a fair service call fee wasn't cheep --

Walk in -- twist a valve and hold our your hand for XX.xx

Sure -- sounds great when you write it -- ever try it?

but -- go in recognize the problem - go back out the truck -- drag in the big Pullman vac - clean under and about the gas train - leave a little blood on the job - twist the valve on the way out

----

happy customer

-- it looked like I did something

tjzmc · Post by **tjzmc** » Wed. Nov. 04, 2009 9:53 pm

steamup wrote:
tjzmc wrote: There is two inch iron pipe supply and returns in the basement that have 3/4 inch supply and returns branching off to each radiator. The problem is that when it calls for heat the circulator runs for about maybe a minute and it sucks all of that cold water into the boiler and then shuts off. The boiler has to run for awhile to heat the water up and then the proccess starts over again until it gets caught up. My plan is to split the system into two or possibly three zones.
Why split it up - to add zoning for comfort or to solve the "problem"?

What is the problem? - cold water into the boiler could be. If a steel boiler, thermal shock is not as big of a problem as cold return and condensation in the fire box. (increased corrosion). You want to maintain at least 140 deg. return water temp to a boiler unless you have a condensing type gas fire boiler.

It sounds like the system is a converted gravity system. Large supply mains with individual branches to radiators. I bet the mains and branches are precisely sloped. I have had no problem running forced circulation into gravity systems but one must understand that most old gravity systems have large mass and ample heating capacity.

I suspect that the thermostat calls for heat, the pump starts and the large mass of the gravity system overwhelms the boiler mass. The boiler then has to fire hard to catch up.

Look at your pump sizing. The gravity system will have very low head requirements. Use a small pump to supply the system. Low flow with high deta T. will move enough BTU's to keep you comfortable and smooth out the boiler operation.. Maybe look at primary secondary pumping for the boiler and gravity system.

By looking at the pipes they precisely sloped and it has a big circulator pump with 1 1/4 iron pipe on both sides. This weekend if everything goes as planned I am going to run 1 1/4 cooper from the pump to both returns on the boiler plus 1 1/4 copper balance pipe as they call it to the supply side of the boiler with valves in both so I can balance the flow. Right now it is only returning to one side and the balance pipe is 2" and stays very hot all of the time (no water going to supply)and no valves. Then I will let it go for the rest of the winter if this works I will probably not split the system into zones.
Thanks For all of the replies

CapeCoaler · Post by **CapeCoaler** » Wed. Nov. 04, 2009 11:34 pm

I have a one hour minimum charge for a service call...
If the people are nice and I just push a button to get the computer going again...
I fill the hour out updating the computer software...
They paid for the hour I work the whole hour...
And it usually ends up in repeat business or good referrals...
If they are people insisted that I come over or made it to be more of an emergency than it really was...
I just push the button and get paid...
Service work is hard, the overhead, the time wasted on travel...
One job at two hours is better than three separate jobs at an hour each...
I also give out free advice...
Did not want to go to P'town over the holiday weekend due to traffic...
The bill would have been over $400 in travel time alone...
The guy was nice on the phone but desperate to have the computer working...
Told him to try two things that may fix it or talk to someone in town...
The tip worked and the guy called back to thank me...
Be fair but firm because your time and knowledge is valuable...
Just not tangible...

I agree with sting
Slow the volume of water and things will be fine...

steamup · Post by **steamup** » Thu. Nov. 05, 2009 9:08 am

By looking at the pipes they precisely sloped and it has a big circulator pump with 1 1/4 iron pipe on both sides. This weekend if everything goes as planned I am going to run 1 1/4 cooper from the pump to both returns on the boiler plus 1 1/4 copper balance pipe as they call it to the supply side of the boiler with valves in both so I can balance the flow. Right now it is only returning to one side and the balance pipe is 2" and stays very hot all of the time (no water going to supply)and no valves. Then I will let it go for the rest of the winter if this works I will probably not split the system into zones.
Thanks For all of the replies[/quote]

Whoa, wait a minute. It is tough to understand what you are up to in your description. You may be doing work that is not really needed.

A simple sketch might help understand the issue. You may only need to add a valve on the discharge side of the pump to slow the water down.

Most hot water boilers don't need both returns piped.

Sting · Post by **Sting** » Thu. Nov. 05, 2009 9:59 am

steamup wrote:
Whoa, wait a minute. It is tough to understand what you are up to in your description. You may be doing work that is not really needed.

thank-you -- That's exactly the point I was inept at making!

tjzmc · Post by **tjzmc** » Thu. Nov. 05, 2009 6:09 pm

If you go to the EFM manufactures page and then " FAQ and specilized info about efm products #2". Then go to "Reasons for using both return line and the bypass line". I am going to do what is explained in that post. I was calling the bypass line a balance pipe oops. Right now I am only using the return on the aquastat side.

tjzmc · Post by **tjzmc** » Sat. Nov. 07, 2009 8:22 pm

I just got done adding a line to the other return, a smaller bypass line and valves on both the return and bypass yo adjust the balance. What a difference. It's working great and no leaks!

Sting · Post by **Sting** » Sat. Nov. 07, 2009 9:27 pm

That's good news!

steamup · Post by **steamup** » Mon. Nov. 09, 2009 12:28 pm

tjzmc wrote:If you go to the EFM manufactures page and then " FAQ and specilized info about efm products #2". Then go to "Reasons for using both return line and the bypass line". I am going to do what is explained in that post. I was calling the bypass line a balance pipe oops. Right now I am only using the return on the aquastat side.

I follow you now. Seems like you are on the right track. Good luck.

journeyman · Post by **journeyman** » Wed. Nov. 11, 2009 6:01 pm

your old cast piping has been in your house since the 1950's. you have only one zone. and you want to control the heat in your rooms? by all means replace the outdated iron piping. here are the numbers to remember.

1/2 coppper pipe 15,0000 btu's
3/4" copper pipe 40, 0000 BTU's
1" copper pipe 75,000 BTU's
11/4" copper pipe 160,000btu's

forget the garbage posted perviously, install 1"x3/4" tees with a balancing valve on the return, ball valves on the supply. install a new 007 pump with flanged ball valves, 3 zone valves and thermostats, enjoy the heat knowing you have a heating system thats not going to suprise you at 3am on the coldest night of the year with a leak in the old piping, im not trying to impress you with delta t numbers or a lot of technical jargon, just plain and simple if you try heating your system with 1/2" pipe remember my numbers all you can achive from 1/2" pipe is 15, 000 but's, the old plumber was a lot smarter that a lot of folks give him credit,

journeyman · Post by **journeyman** » Wed. Nov. 11, 2009 6:12 pm

a service call to help you with your problem? without me or my techs getting their hands dirty? come on, we help you with your problem and know I have a friend and possibly a customer for life, you tell your friend and the ball is rolling, thats what is called building business, and its the old fashion way of doing business, thats one of the reason's for my sucess treat people right and the business and money will take care of themselves.