HOT WATER ZONES OFF STEAM BOILER

Mike_NYH

I have a W/M 988 steam boiler with (4) 8 gallon coils to provide domestic hot water for 37 families.  Off this boiler there is (3) 3/4" zones with Taco 007 iron body circulator pumps.  Alot of banging is occuring in the hot water zones mainly because steam is gettin into those lines.

What can i do to resolve this issue?

I had an idea to install flow control valves but i actually wanted to make more of a job out of it because the customer im dealing with is willing to do anything with us.  Can i install an everhot or equivalent tankless hot water coil and take a steam line off the boiler with a recirc line etc. to get some kind of system where the banging will be eleminated. 



Any help is greatly appreciated, thank you.

DanHolohan

This will help.

http://www.heatinghelp.com/article/17/Hot-Water/76/Condensate-Hot-Water-Heating

Mike_NYH

ALL GOOD STUFF BUT.....

Thanks.

If i piped these (3) hot water zones off 1 of the existing 4 coils can i just use 1?  Also would i have any problems with my domestic hot water.

I have (4) 8 GPM coils

I have 37 families in the building

Now the formula i use which is a rule of dumb i was tought is:  3 gallons for the first family and then 1 gallon for every family after that.  So for 37 families i need enough coils to provide 39 gallons.  On the job like i mentioned already is (4) 8 gallon coils which is a total of 32.  Now even though that seems a little undersized there has never been any complaints in the building so i wanted to make sure if i used 1 of the coils in the boiler as my heat exchanger instead of an everhot would i have any problems?

DanHolohan

It's a game of subtraction, Mike.

You can only use the steam boiler's pick-up factor. This will help explain:



http://www.heatinghelp.com/article/11/Hot-Tech-Tips/201/Hot-water-zone-off-a-steam-boiler

clammy

seperate boiler

How about  a seperate hot water boiler  for the hot water zones and a indirect off of the new hot water boiler ,your custermer may end up using alot  less fuel with this set up by not having to maintain the steam boiler to satisfy the limit control for domistic hot water 24 /7/365,this is just an idea which i have done in the past for some very old and large homes(10 to 15,000 sq.ft) You would be very suprised how much fuel is used to produce hot water in that type of set up  and how those hot water zones effect  steam production and also how effiecent is a steam boiler in production of either domestic and heating hot water not very well  . Also take a look at turbomax indirects they are very well made and have some very exceptally outputs and can be custom designed to meet any domestic water loads  and from what i have heard have a very good lifespan at least 20 years if properly installed . On one last note have you looked at tankless hot water  heaters like noritz they are real mizers on fuel and an be daisey chained to meet any load i like most was very spectical at first and after installing one i was a little amazed at exactly how much they could delivery and after installing a recirc pump tied into the boiler recirc wires with a aquastat to shut the pump off one the line was hot  there was really no cold water sandwich when the pump was installed .But i do feel that take a very small zone off a steam boiler is no big deal but when your taking and running a couple off zones of it it starts wasting alot of fuel unless your  the fuel supplier then that's good  peace and good luck clammy