Several boiler installation problem

stuckinthedirt

I need to install a new hot water boiler on my home.  I currently have a 5 section burhnam V7 with a crack in it (burhnam will only give me $ for a new boiler if I install an EXACT replacement).   Boiler is about 13 years old, house is 50 years old.   My total baseboard radiation is about 120k BTU/hr (most of this is one zone for the living space, with a little for a second zone for the basement).  I am currently very comfortable in my home, and even on the coldest nights (0 F) the boiler seems to only run about half the time.    Most boiler installers around here do not do heat load calculations - they either want to install an identically size replacement boiler (about 190k BTU/hr) or they size on radiation.  I ran a heat loss calc using the Slantfin program which gave me a load of about 100k BTU/hr.



Couple questions: 

1. If I install a ~100k BTU/hr boiler for my home am I at risk of cold spots since I have radiation for 120k BTU/hr?

2. Do I risk problems with cold water return shocking my boiler in this case as well?  I see that the Buderus has a built in cold return bypass.  How about other brand (I also have quotes on a NY boiler, Weil McLain, and Burhnam)?

3. My current circulator setup pumps INTO the boiler on the return.  It seems to work fine.  Is it really necessary to add the expense to repipe for pumping AWAY if my current setup works?



Thanks for the input.

CMadatMe

Stuck

I think you are misinformed. Burnham will give you  reabte in the form a check after the replacement installation. You must use a V8H or MPO and I would suggest the MPO. Take a look at the MPO147 or MPO115. How did you come up with the btu ouput of the radiation.? Did you base it on 1gom flow rate? If so your telling me you have about 215' of board in the house. Which is a good thing in the aspect you may be able to run some lower water temps. You don't have to worry about shocking the MPO it has an injector in it.

stuckinthedirt

baseboard

Wizard,



I have 161 feet of copper fin baseboard in my living space, plus another 31 feet in my semi-finished basement.  I was using the value of 600 BTU per foot.



On the Burhnam would the rebate apply only if installing one of the two oil boilers you mentioned, or could it apply if I switched to a gas boiler too?

CMadatMe

You'd Have to Speak

with them concerning that. I believe as long as it is a burnham product they will give you the rebate. Your just getting the remainder of the warranty in dollars. It's the smart thing to do. You end up with a current system and a full warranty

heatboy

The amount of baseboard......

.... doesn't mean anything when it comes to sizing a boiler for your home.  It does come into play as to water temperature you can run through it. 

CMadatMe

I agree with Heatboy

I pick up that you did a heat loss. I was curious as to the foot of board as a comparision to the heat loss. Since you did a loss break that loss out to zones and rooms. Take the flow rates that you need for each zone, the footage of board in each room per zone and utilizing the the baseboard charts for the brand of board installed find yourself the water temp you need to get the output you need at design temp. I would strongly encourage you to look at using a zone control with outdoor reset capability to further save you some fuel dollars.

stuckinthedirt

OK, thanks

I only have two zones - the living area, and the basement - so I can't do much with zone controls.  I am however interested in an outdoor reset.



I did the heat loss calcs myself using the Slantfin program because I couldn't find a contractor in my area to do them.  I live in a "smallish" town - most either want to put in the same size boiler, or want to size based on baseboard.  I used the coldest temperature I have seen in 15 years as my design temperature.



As for my circulators, they are on the return.  I have read much on the wall about pumping away.  My current system, however seems to be running fine.  The circulators are quiet, no indication that I am getting cavitation, and I don't ever get air when I bleed the vents on the baseboards.  Based on what I have read, I understand the advantages of pumping away, but since my current system seems to run fine, is it worth the added expense of repiping the circulators on my new boiler?



Thanks,

Ed

bob eck

burnham boiler

if you are looking at going to gas boiler look at high efficiency 95% AFUE burnham alpine boiler with a burnham alliance indirect water heater. Alpine boiler comes with a outside reset control.

vents sidewall with pvc pipe no chimney needed.

this boiler qualifies for federal tax credit of 30% up to $1500.00 some states and local gas utilities are also offering tax credits and rebates. check it out in your area.

how old is your oil tank will it need to be replaced soon?

have a contractor add copper baseboard so you can run low water temp in all your zones. the lower water temp you run the lower your energy costs will be.

I live in a old 1/2 double home near Allentown Pa. went from a 33+ year old weil meclain oil boiler to a triangle tube 95% AFUE prestige excellence boiler with a built in stainless steel indirect water and I have cast iron radiators and this winter I spend about $1200.00 for nat gas and I would have spent about $2000.00 for oil with my old boiler and I know I could have lowered my oil bill with a new MPO boiler and Alliance IDWH but I also would have needed to replace old oil tank and also put a 45' stainless steel liner in the old chimney plus no federal tax credits on oil unless you go to Buderus high efficiency oil boiler.

What part of the country do you live in you can check with Burnham for qualified contractors in you area that can install their MPO oil boiler or Alpine high efficiency gas boilers.

stuckinthedirt

50 yr old oil tanks

I still have the original 50 yr old oil tanks (2 - 275 gal tanks).  They are in my basement.  The outsides look good, but I can't tell you about the inside.  I have not inspected.

I seem to hear various opinions about the hi-efficiency mod/con boilers vs. the standard 80-85% boilers.  The concern that some raise is that the mod/con parts are much more expensive, and so the maintenance can erase much of the savings in fuel.

I live in the Shenandoah Valley in Virginia.  I know of several Burhnam installers here.

As for length of baseboard - if I have equivalent of 120MMBTU/hr of baseboard (@ 180 F) but a max load of ~100MMBTU/hr I should be able to run a significantly lower boiler temp most of the time - correct?

Steamhead

Definitely Pump Away

and add a good air separator. When you take out the old boiler you will have to drain the system, and when you refill the fresh water will have a lot of air in it that you will need to get rid of. Pumping Away makes this easy. We don't install our boilers any other way.



Regarding the Alpine and other mod-con boilers, these cannot use a standard chimney. Unless you can use the existing chimney for a chase, you will have to vent this type of boiler thru the sidewall. The pipes must exit the house at least a foot above the highest recorded snow accumulation for your area, otherwise they can clog with snow, and the boiler will shut down (if the safeties are working properly) or operate unsafely (if they're not). Also, the pipes must be far enough from doors and windows- check your local Codes- and must not be longer than the manufacturer's specified developed length.



If you can't meet these requirements, don't get a mod-con.

stuckinthedirt

SNOW!

Wow, thanks for the info on the snow!  Definitely a big snow year here.  We got the most snow of the last 15 years this year (and we missed a couple big ones that hit DC/MD).  I'll have to ask about venting a mod/con out my chimney where my current oil fired boiler vents.

bob eck

boilers

burnham alpine come with a 5 year parts and labor warranty.

if you go with triangle tube prestige boiler you can get up to 10 years parts and labor warranty. great deal

stuckinthedirt

warranty

Bob,

You must be looking at a different warranty than I can download from their websites.  The warrany I can find explicitly EXCLUDES labor of any kind, even in the first  year.

Please send me a link to the warranty you are looking at.

Thanks.

bob eck

warranty

go to burnham.com look under products then click on alpine boiler than click on down load literature 4 pages states on that piece of literature 5 year parts and labor warranty comes with the boiler

triangle tube 5 or 10 year parts and labor warranty bust be bought by the installing heating contractor and sold to you the home owner.

AMH112181

go gas

I would go gas or replace the oil tanks as well.  If they are that old they are on borrowed time IMO.