New boiloer install questions


  #1  
Old 07-10-09, 04:41 PM
A
Member
Thread Starter
Join Date: Jul 2009
Location: Fairbanks
Posts: 24
Received 0 Votes on 0 Posts
Question New boiloer install questions

Going to install a new boiler system. Have a 35 year old WM with 3 zones (with zone valves).
Putting in new Burnham MPO with a super store indirect heater. Questions?

Is there an advantage to using zone valves or putting in circulators?

Should the system circulator be placed on the return or supply side? Which is better?

My boiler is in the garage and the boiler is at one end (where the oil line comes in) and the zone valves are on the other end. Would it be better to put the indirect heater on the side closer to the boiler or on the other side closer to the zone valves?

Do I need a separate circulator for the indirect heater? If so how is that wired up?

Thanks for any help!!!
 
  #2  
Old 07-10-09, 05:09 PM
F
Member
Join Date: Mar 2006
Location: Wet side of Washington state.
Posts: 18,495
Received 36 Votes on 28 Posts
Is there an advantage to using zone valves or putting in circulators?
Zone valves that use heat motors are more prone to failure than are circulators, in fact, all zone valves are more prone to failure than are circulators. On the other hand, zone valves ar usually less expensive than circulators and since most zone valves allow for the replacement of the actuator (motor) without draining the system it can be stated that maintenance and repair of zone valves is easier than circulators.

If you have a single circulator and it fails you have no heat at all in the house whereas if you have multiple circulators and one fails you will have heat in the other zones. Although it will add to the cost, I recommend isolation valves on any circulator to enable changing of the circulator without having to drain the system.

Should the system circulator be placed on the return or supply side? Which is better?
The system circulator should ALWAYS be piped so that it "pumping away" from the "point of no pressure change" which is usually the expansion tank. For most multi-zone systems this means piping the circulator on the boiler outlet.


My boiler is in the garage and the boiler is at one end (where the oil line comes in) and the zone valves are on the other end. Would it be better to put the indirect heater on the side closer to the boiler or on the other side closer to the zone valves?
The indirect water heater should normally be piped directly from the boiler out and return rather than as part of the space heating loop.


Do I need a separate circulator for the indirect heater? If so how is that wired up?
A separate circulator is best for the indirect water heater. Wiring is most easily accomplished by using a zone control system that has provisions for an indirect heater.


Thanks for any help!!!
You're welcome. If you have more questions just ask.
 
  #3  
Old 07-11-09, 03:58 AM
X
Member
Join Date: Nov 2005
Location: USA
Posts: 2,458
Received 0 Votes on 0 Posts
Here's the directions. Follow all of them.

http://burnham.com/PDF/IO/MPO.pdf

I suggest Figure 18A for water piping.
 
  #4  
Old 07-14-09, 06:24 PM
A
Member
Thread Starter
Join Date: Jul 2009
Location: Fairbanks
Posts: 24
Received 0 Votes on 0 Posts
I'm looking at the taco circulators with integrated flow checks. Are these considered a good bet or would it be more dependable to go with separate flow checks?
 
  #5  
Old 07-15-09, 05:03 AM
X
Member
Join Date: Nov 2005
Location: USA
Posts: 2,458
Received 0 Votes on 0 Posts
I have two Taco 007IFCs. Work fine. Now that the new ECM circulators (very electrically efficient, not cheap...) are out, however, I kinda wish that I'd gone with separate checks.
 
  #6  
Old 07-15-09, 09:33 AM
rbeck's Avatar
Member
Join Date: Jul 2007
Posts: 2,501
Received 9 Votes on 7 Posts
Why do you wish you would have gone with separate flow check's?
 
  #7  
Old 07-15-09, 05:59 PM
X
Member
Join Date: Nov 2005
Location: USA
Posts: 2,458
Received 0 Votes on 0 Posts
Because I would have bought a couple Wilo ECO's and just stuck them in there. Simple. No need to change any piping, control, relays, etc. etc. Payback on a simple swap would be 4 yr. (Electricity is 23 cents/kWh here). Adding new external flowchecks (e.g., B&G checktrol or Taco Swet-chek) lengthens it quite a bit. Plus everything fits quite nicely as is.
 
  #8  
Old 07-16-09, 11:43 AM
A
Member
Thread Starter
Join Date: Jul 2009
Location: Fairbanks
Posts: 24
Received 0 Votes on 0 Posts
circulator sizing?

So I am now leaning towards the Taco Circ with FC instead of going with zone valves.
My zones are as follows

1 has a length of about 20 feet
2 has about 80 feet
3 has about 100 feet
and 4 is the indirect water heater (Superstor Ultra) 45 gallon which states a flow rate of 10 and pressure drop of 7.9.

What would be the best sizes of circs for these (Taco 007)?

Also, what is "head range" refer to?

Thanks
 

Last edited by Alaskanstar; 07-16-09 at 01:47 PM.
  #9  
Old 07-16-09, 05:20 PM
X
Member
Join Date: Nov 2005
Location: USA
Posts: 2,458
Received 0 Votes on 0 Posts
Oh if it were only that easy....

The real way to figure the proper circulator size is here:

http://www.taco-hvac.com/uploads/Fil...irculators.pdf

Doesn't take too long.

The shortcut is to just use a 007 for each zone and live with some overpumping of short zones. Some of the smaller sizes can be hard to find. The 007 is ubiquitous.

Ordinarily I would say for a 3-zone system to go with zone valves and a single ECM variable speed circulator, OR zone valves and something like a 007 plus a pressure differential bypass valve. But in Fairbanks (where ASHRAE says the outdoor design temperature is -47F), having a bunch of circs pumping water is probably a good thing. One goes down you can still run the others or even move one to another zone. Of course, if you go single circ then you could also just keep a spare or two on the shelf....

For whatever circs you choose, use some nice isolation flanges, such as these: http://www.taco-hvac.com/uploads/Fil...ry/101-101.pdf

For the indirect, you could do a Taco 00R 3-speed on medium,
http://www.taco-hvac.com/uploads/FileLibrary/100-51.pdf

or a 007.
 
  #10  
Old 07-20-09, 05:34 PM
A
Member
Thread Starter
Join Date: Jul 2009
Location: Fairbanks
Posts: 24
Received 0 Votes on 0 Posts
If I follow figure 18B (on the Burnahm MPO installation manual), where in the system would be best to install the differential bypass valve?
 
  #11  
Old 07-20-09, 06:20 PM
X
Member
Join Date: Nov 2005
Location: USA
Posts: 2,458
Received 0 Votes on 0 Posts
You would place it at the end of the supply manifold (after the last zone valve) and tie it into the return manifold. If your manifolds are close to each other, this is a simple, short piping run.

Can't think of a good diagram that shows a PDBV piped to a standard boiler, but here's a diagram for essentially the same application (adjacent supply/return manifolds with zone valves) for a different boiler:

http://www.htproducts.com/literature/lp-185.pdf

Figure 2B on page 23.
 
  #12  
Old 07-20-09, 06:35 PM
A
Member
Thread Starter
Join Date: Jul 2009
Location: Fairbanks
Posts: 24
Received 0 Votes on 0 Posts
OK, that looks simple since my manifolds are close by each other. Thanks. So now I am thinking I am going to go ahead and do the zone valves with a 007 system circulator. I think I will buy another just to have on hand. Don't want to be like last year and hit -60 and have mine go out at 2 AM.
Thanks!

Also, on a side note. I keep seeing these vented on the manual through a chimney. I don't have a chimney on my current boiler, just the pipe going straight up through the ceiling. Any problems with this?
 
  #13  
Old 07-20-09, 07:37 PM
X
Member
Join Date: Nov 2005
Location: USA
Posts: 2,458
Received 0 Votes on 0 Posts
Not familiar with what the various codes would require for venting, clearance to combustibles, piping schedule, etc., so can't help there. Hopefully someone else will chime in.
 
  #14  
Old 07-20-09, 08:23 PM
B
Member
Join Date: Jun 2009
Location: Fairbanks Alaska
Posts: 92
Received 0 Votes on 0 Posts
zone circs

I NEVER use a circulator on every zone. It uses a lot more power. Also, I usually have more than 3 zones so the extra cost adds up. I just don't see an advantage of a bunch of circs, especially if you already have a boiler set up with zones. I would not even consider the extra work and expense. We have thousands of boilers here in Fairbanks with one circ, including huge houses, including 3 stories and have never had a lack of circ with the standard circ pump that comes with the boiler. The MPO is very popular here btw.
I don't put a separate pump on the domestic tank either, simply another zone valve wired with all the rest. Easy.

I usually put about 6 zones in a house. If you have a boiler, why not enjoy the savings of lots of zones.
How often do you see a failed main circulator? Very rare. My house, the circ is 25 yrs old! It is on the 1st System 2000 in the state.

Also very dependable, are the Honeywell zone valves that spring closed. It is a simple low voltage circuit from t-stat, to zv to 24v transformer to open the zone. The red end zone pair bundle and goes to the boiler TT.
 
  #15  
Old 07-20-09, 08:25 PM
B
Member
Join Date: Jun 2009
Location: Fairbanks Alaska
Posts: 92
Received 0 Votes on 0 Posts
Neighbors

We are neighbors. I can stop by and give you a hand if you like. Kevin
 
  #16  
Old 07-21-09, 05:34 AM
rbeck's Avatar
Member
Join Date: Jul 2007
Posts: 2,501
Received 9 Votes on 7 Posts
A bunch of zones????? Micro zoning is never a good thing. You are worried about the use of power from small circulators and then micro-zone so the boiler short cycles and decreases the efficiency. It may be wasting more fuel that way then a bunch of wet rotor circulators would be wasting electric. Everything has limits. If you want to be Green, Keep zoning to a minimum, use zone valves, properly size the boiler, proper near boiler piping, DPBV, and combustion test to complete the job.
 
  #17  
Old 07-21-09, 06:26 AM
A
Member
Thread Starter
Join Date: Jul 2009
Location: Fairbanks
Posts: 24
Received 0 Votes on 0 Posts
Thanks Bilbo

What you are saying is what I thought at first but then as I got further into this install and started reading other ideas I wasn't sure what was best or not.
I am going to be doing this install when I get back home in early Sept. Thanks for the offer, I may take you up on it.
 
  #18  
Old 07-21-09, 12:16 PM
A
Member
Thread Starter
Join Date: Jul 2009
Location: Fairbanks
Posts: 24
Received 0 Votes on 0 Posts
I am wondering now, what would be the easiest thermostats to install?
I would like to have a programmable model but I know I replaced one about a year ago and had a heck of a time trying to wire it to the existing 2-wire system. Somehow I got it hooked up and it works but I was wondering if there may be a certain model that would be better for a 2-wire system?
Thanks.
 
  #19  
Old 07-22-09, 04:12 AM
B
Member
Join Date: Jun 2009
Location: Fairbanks Alaska
Posts: 92
Received 0 Votes on 0 Posts
Alaskanstar- I am in the book: KevinCorr. I am putting in an MPO next week.

Rbeck- I disagree. I have read research that indicates that not heating areas of the house that you are not using saves energy.
Studies show that you can save up to 18% that way.
When I first sold System 2000 the system manager was set up for 4 zones. They use spring shut, power on Honeywell ZV. They quickly changed it to 5 zones standard, and made a diagram for combining two managers for 10 zones. I don't work with it now, but I think they have made that into one optional big manager.
You can call or email them if you want some evidence.
 
  #20  
Old 07-23-09, 12:59 PM
P
Member
Join Date: Jul 2009
Location: NY
Posts: 1
Received 0 Votes on 0 Posts
Post Hot Water Gas Fired Boiler

Hi Alaskastar and Bilbo,

I enjoyed reading your emails. I have a new question. I like to run it by you because you seem to be very knowlegeable on boilers and controls.

Last week, I replaced a 45 year old HydroTherm hot water gas fired boiler with a new HydroTherm HW 100-8, 175K BTU/hr unit (single circulator). The 4 tstats and 4 Honeywell zv's are existing. The new boiler comes with a control center. The control center has a 24V step down transformer. We completed all the piping, gas line and flue duct. We jumped across the tstat terminals in the control center to test, the boiler fired up nicely. Now we are ready to hook up the electrical.

The control center in the new boiler has a 24V AC stepdown transformer. I believe this new 24V AC source can power up all the thermostats and zone valves in the system. The thermostat wiring shown in the diagram is for only one tstat only. There is no example diagram on tie-ins with zv's. My old control had one 24V transformer and one Honeywell RA832A controller (two separate pieces). The Honeywell 832A activates the circulator and opens the gas valve. What will be the easiest way to re-wire the tstats and zv's for this new boiler?

Thanks,

plin1
 
  #21  
Old 07-23-09, 05:57 PM
rbeck's Avatar
Member
Join Date: Jul 2007
Posts: 2,501
Received 9 Votes on 7 Posts
If the boiler has a certain output and has many smaller zones the AFUE efficiency will absolutely be affected. If a zone of 1/5th the total input the boiler will short cycle. The boiler needs to run 5-7 minutes to hit peak efficiency. If short cycling does not affect efficiency and fuel consumption why do we properly size boilers, install modulating boilers and use buffer tanks?
There are more than one manufacturer that will disagree with the theory of saving fuel by not heating areas. The interior walls are not insulated. For example, heat a dinning room to 70f. The bedroom on the other side of the dinning room wall is 65f. The wall in the dinning room will cool quicker causing the room to cool down quicker and the thermostat will call quicker. Some homeowners today go to extremes and will try to set the setback thermostat in the bedroom area down as low as 10f. Not the bedroom is 60f and the dinning room is 70f. The cool down is even more than before.
Siggy proved mathematically that cast iron has about the best thermal transfer of any product which also is different than one company states.
 
  #22  
Old 07-24-09, 03:41 AM
B
Member
Join Date: Jun 2009
Location: Fairbanks Alaska
Posts: 92
Received 0 Votes on 0 Posts
I am not a wiring or electric or electronic expert, just a pipefitter, plumber who has been forced to learn enough to install boilers.
All that I would say about wiring Honeywll zone valves is that if you have honeywell spring closed zone valves, that the 24 volt circuit loop from the transformer to the zv motor yellow and orange to the the thermostat and back to the transformer is a simple circle that does not go to the boiler. The zv end switch has two red wires which you jump to the next zone valve and send one pair to the boiler TT.
 
  #23  
Old 07-24-09, 03:53 AM
B
Member
Join Date: Jun 2009
Location: Fairbanks Alaska
Posts: 92
Received 0 Votes on 0 Posts
rbeck- "...Siggy proved mathematically that cast iron has about the best thermal transfer of any product which also is different than one company states..."

Some boilers are made of steel instead of cast iron NOT for thermal transfer but for durability and flexibility for a low mass boiler that can come from room temp to 160 or 180 in 1.5 to 2 min and cool back down not leaving energy in the boiler.
The idea is to make a boiler work like a hot air furnace which would not be heavy cast iron.

So theory schmeary, lets look at real world contests:
Against the old type cast boilers that sat hot all the time (still sold for some unknown reason) the cold start steel boiler used 40% less in identical tract homes. I went there in the late 1980s and visited the installer too.
Now that the cast boilers have adopted the modulating temps (ala Buderus etc) the steel cold start boiler only won by 40 gal in a similar recent test here. That was only two houses so it is not definitive yet. Close enough to call a tie. I would say that the type of system to choose would depend on the size and design of the house.
 
  #24  
Old 08-03-09, 04:45 PM
A
Member
Thread Starter
Join Date: Jul 2009
Location: Fairbanks
Posts: 24
Received 0 Votes on 0 Posts
So, I am refining this install.
So far I am now going with the following

Burnham MPO 115 with Supply side Taco 007
Honeywell zone valves
Taco 3 zone control with priority
Super Stor Ultra 45 gallon indirect

Question is, will the MPO 115 be able to supply the 45 gallon indirect?
Specs are as follows

MPO 115 BTU 115,000

Super Stor Indirect (45 gallon) Says it needs a BTU of 141,000 ( for 180 degrees) or 161,000 ( for 200 degrees)

The only superstor tank that says it needs the BTU that is the same range as the MPO 115 output is the 30 gallon tank. Does that mean, that is the largest tank I can put with this boiler??

Maybe I am interpreting all this wrong?

I have a family of 4 with 2.5 baths in the house. We do have one soaking tub in one bath. Would a 30 gallon indirect be enough? I don't think there would be a problem since recovery time is short.
 

Last edited by Alaskanstar; 08-03-09 at 05:08 PM.
  #25  
Old 08-03-09, 04:56 PM
X
Member
Join Date: Nov 2005
Location: USA
Posts: 2,458
Received 0 Votes on 0 Posts
Yes it will. Those are the ideal specs. With priority, you will devote the full output of the boiler to making hot water for 10-15 minutes. Recovery should be fine.

FWIW, I fire a 96,000 boiler into one of the world's worst indirects, and it does fine.
 
  #26  
Old 08-05-09, 11:18 PM
B
Member
Join Date: Jun 2009
Location: Fairbanks Alaska
Posts: 92
Received 0 Votes on 0 Posts
I agree. I have done it without the hw priority and it works fine in a duplex with 2 apartments. I thought maybe we would come back and add the domestic hw priority control but they just cranked the temp up a little and had no problem.
 
  #27  
Old 08-13-09, 12:46 PM
A
Member
Thread Starter
Join Date: Jul 2009
Location: Fairbanks
Posts: 24
Received 0 Votes on 0 Posts
This may be a really dumb question but I figure I had better ask anyway, in case there is something I am missing.

As I stated earlier in this thread, my boiler is about 14 feet from where the zone valves are located. This is due to the fuel line inlet in the garage.
Is there any issue with having the zone valve for the indirect water heater branch off the main supply line closer to the boiler? So the zone would be about 4 feet down the supply with the other zone valves being about 14 feet away.
To me it doesn't seem to matter but I thought I would check.
Thanks!
 
  #28  
Old 08-13-09, 03:04 PM
T
Member
Join Date: Jul 2009
Location: Toronto
Posts: 1,174
Received 0 Votes on 0 Posts
Originally Posted by Alaskanstar View Post
This may be a really dumb question but I figure I had better ask anyway, in case there is something I am missing.

As I stated earlier in this thread, my boiler is about 14 feet from where the zone valves are located. This is due to the fuel line inlet in the garage.
Is there any issue with having the zone valve for the indirect water heater branch off the main supply line closer to the boiler? So the zone would be about 4 feet down the supply with the other zone valves being about 14 feet away.
To me it doesn't seem to matter but I thought I would check.
Thanks!
Other than stopping migration and conduction, it does not mater where the zone valve is.
There can be some weird side effects of having a zone valve in a bad spot in relation to the circulator, but it will do its job anywhere in the branch line, it will offer the same restrictions to flow anywhere.
 
  #29  
Old 08-13-09, 03:12 PM
Who's Avatar
Who
Who is offline
Member
Join Date: Jan 2006
Location: San Jose
Posts: 2,175
Received 1 Vote on 1 Post
Alaskanstar, I'll echo the need to carefully examine your zoning requirements. The whole concept of more zones in a house being more economical only exists when the home is poorly designed and/or constructed. Otherwise, the zones that aren't heating get heated by those that do and all you are doing is decreasing the load each heat call and increasing your cycling. Increased cycling decreases efficiencies.

The ideal for me is everything in one zone and in those spaces where you want to fine tune the heat, install TRVs. With an ECM pump and TRVs you'll have low pumping/circulation costs and incredible comfort.

I would use a separate and properly sized pump for your DHW.
 
  #30  
Old 08-13-09, 10:10 PM
B
Member
Join Date: Jun 2009
Location: Fairbanks Alaska
Posts: 92
Received 0 Votes on 0 Posts
One zone

One zone is good for a one room house.
 
  #31  
Old 08-13-09, 10:16 PM
B
Member
Join Date: Jun 2009
Location: Fairbanks Alaska
Posts: 92
Received 0 Votes on 0 Posts
Coincidentally, I will be finishing and starting up a new MPO tomorrow, Aug 14 on Farmers Loop. 6 zones, 3 radiant floor and 3 baseboard areas upstairs.
 
  #32  
Old 08-13-09, 11:52 PM
Who's Avatar
Who
Who is offline
Member
Join Date: Jan 2006
Location: San Jose
Posts: 2,175
Received 1 Vote on 1 Post
Bilbo, could you show us some pictures of the 6 zone system? Did you do a heatloss calculation for the house? How many BTUs are the smaller zones? What size is the MPO?
 
  #33  
Old 08-15-09, 01:26 AM
B
Member
Join Date: Jun 2009
Location: Fairbanks Alaska
Posts: 92
Received 0 Votes on 0 Posts
Mpo 115

The MPO 115 is 98/85 MBH.

It is convenient now here for heat loss because the state of Alaska has a program for cash rebates up to $10,000 and loans up to $40,000 if you get an energy audit by a state certified rater who files a report on what you should do to improve your house. As you follow the guidelines recommended you get points toward the rebate. They do the whole blower door and thorough house exam.

As for pics, since I only replaced the boiler and not the existing zones and domestic hot water there is not much to show to separate my work from the old stuff.
It is typical of the houses in this climate.
Zones:
1- Living, dining
2 and 3 bedrooms
4- office
5- rec room
6- garage
 
  #34  
Old 08-31-09, 01:32 PM
A
Member
Thread Starter
Join Date: Jul 2009
Location: Fairbanks
Posts: 24
Received 0 Votes on 0 Posts
This message is really focused for those on the board in Alaska.
I am wondering about state code on some boiler items and what is or is not required.

Low water cut-off?
Height of boiler off of floor?
Boiler bypass line?
System limit?

Thanks for any assistance.
 
  #35  
Old 09-02-09, 08:14 PM
B
Member
Join Date: Jun 2009
Location: Fairbanks Alaska
Posts: 92
Received 0 Votes on 0 Posts
State

The low water cut off is not required on residential here but it can't hurt.

In a garage or basement the burner needs to be 18 inches from the floor. You can get a stand at Fergeson which is a steel plate with 2" pipe for legs.
I most often just use concrete blocks, stacked 2 high with a 2" paver on top. That gives you 18" to the bottom of the boiler.

The bypass is not code but manufacturers instructions.
I just installed an MPO. The instructions say you must install a boiler bypass of the full size with a balancing valve.
I am now doing a Buderus which prefers a controlled mixing valve on the boiler bypass.
If you are in Fairbanks you can call me at 888-8322. I am working near S. Cushman
 
  #36  
Old 09-04-09, 04:03 AM
rbeck's Avatar
Member
Join Date: Jul 2007
Posts: 2,501
Received 9 Votes on 7 Posts
Just for clarification the MPO only requires a boiler bypass since you have radiant zones. If this would be baseboard or zoned radiator system boiler bypass is not required.
The valve in the bypass is not a balancing valve it is a shut off valve. Since a boiler bypass sends cool return into hot supply you need to reduce the flow through the boiler and leave the bypass valve wide open. And yes keep the bypass pipe same size as the supply and return piping.
 
 

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