where to tee in to existing lpg boiler

[huffdawg]

I finally got caught up for a bit with the hearth postings, and was able to do a bit of rough drawing with my CAD program - and created these rough drawings to show a couple of generic hookups... As I find time, I will keep working on doing other designs along the same idea - you may see these drawings fairly often...

The house load, wood boiler, and fossil boilers are identical in both drawings, the only thing that changed is the way they are connected.

I think I have the wood boiler set up right (in one of the many ways it can be done) but there is nothing special about that boiler configuration, any way of hooking up a boiler that has a supply and return coming out would work. You could also substitute the pressure side of an OWB or Garn HX - the same idea applies.

Similarly, the house load is very generic, I just slapped a DHW indirect tank and a few different styles of radiation together to give the general idea...

In the first drawing the two heat sources are in parallel, and are essentially independent of each other. Whichever one is chosen on a call for heat turns on it's pump and circulates through the house load - Again this is very generic - the pumps could also be constantly running temperature controlled, the basic idea stays the same. The flow check in each pump (which could be a discrete component instead) prevents flow through the unused circuit. (In theory it might also be possible to have both heat sources running at the same time, though this would be unusual)

The second drawing uses closely spaced tees to connect the wood boiler into the fossil boiler - house load loop. The pump for the fossil boiler (P3) will run on any call for heat (or again could be an always on pump) so it MUST be able to run without firing the fossil boiler. As I understand the theory of closely spaced tees, you could actually put them any where on the loop that is a main trunk, not just where I have them drawn. If the storage is hot P2 also runs to inject hot water into the loop through the close spaced tees. If the storage isn't hot, the boiler fires and everything works like the wood side wasn't there.

Gooserider

Merry xmas Gooserider. Thanx fo all your time in helping me.

I will be going to pick my new eko 40 up around the 4th. of Jan.
I will be installing it in a detached shop . I will run 1-1/4" pex tubing from there to my lp boiler (roughly a 60' run).
My goal right now is to get it online asap. As my lp boiler costs about $300 a month to heat my place and I have no heat in my shop. I was used to paying nothing till I built this place,always burnt wood.

The 2nd. option you drew looks almost plug and play without the storage. I would be able to use all the control and p/p's from my existing system.
As far as efficiency, I think I would lose barely any as my lp boiler is allready in heated space .

The 1st. option also looks good too. I think I would be able to tee in just above the air extractor without too much hassle. but im just not sure about the control part.

Cheers Huff

 

[Gooserider]

While I strongly recommend storage, it certainly makes sense to skip it if trying to get a system up quickly - but I would try to figure out how I was going to add it later, and include some provisions for it - even it it's just a couple extra tee fittings that are capped off for now...

As to the efficiency question - what sort of LP boiler do you have now? Is it a mod-con style high efficiency unit, (usually wall vented) or a traditional plain boiler? It makes a difference, as the mod-cons don't lose a lot of heat as they rely on a fan for combustion air flow, and have little or no airflow through the boiler if not actually burning... OTOH, you can lose a lot of heat with a traditional boiler, as it will set up a draft flow through the combustion chamber just like it was burning, and pull a lot of heat out of the burner HX...

I think the control part is relatively simple - especially on the parallel setup - essentially design whatever controls are needed to make the wood side deliver heat into the system - then add a double pole relay triggered by an aquastat on the wood side, that sends the house thermostat call for heat to the wood side if it's hot, and the LP side if it isn't...

The close space tee option would use the same approach, but is a little trickier as you have to control both the wood side and the circ for the LP side, while keeping the LP burner from firing...

Gooserider

 

[huffdawg]

While I strongly recommend storage, it certainly makes sense to skip it if trying to get a system up quickly - but I would try to figure out how I was going to add it later, and include some provisions for it - even it it's just a couple extra tee fittings that are capped off for now...

As to the efficiency question - what sort of LP boiler do you have now? Is it a mod-con style high efficiency unit, (usually wall vented) or a traditional plain boiler? It makes a difference, as the mod-cons don't lose a lot of heat as they rely on a fan for combustion air flow, and have little or no airflow through the boiler if not actually burning... OTOH, you can lose a lot of heat with a traditional boiler, as it will set up a draft flow through the combustion chamber just like it was burning, and pull a lot of heat out of the burner HX...

I think the control part is relatively simple - especially on the parallel setup - essentially design whatever controls are needed to make the wood side deliver heat into the system - then add a double pole relay triggered by an aquastat on the wood side, that sends the house thermostat call for heat to the wood side if it's hot, and the LP side if it isn't...

The close space tee option would use the same approach, but is a little trickier as you have to control both the wood side and the circ for the LP side, while keeping the LP burner from firing...

Gooserider

Yes I should be able to cut the 1-1/4 pex supply and return from outside the back wall of my shop and add a few tees.
The eko boiler will be inside my shop and I,ll put my storage outside directly behind the eko.

If I can tee in above the air extractor to left of the copper union and before the dhw p/p on the discharge side of the lp boiler without too much trouble, I will do the parallel setup.

Yes my lp boiler is a modulating condensing Buderus gb 142 .

I guess I should be able to put this relay and aquastat in the house beside my lp boiler on the supply from the eko?

Another thing that im not sure about is if I can run water with treatment in it through my lp boiler.

Cheers Huff

Cheers Huff

 

[Gooserider]

While I strongly recommend storage, it certainly makes sense to skip it if trying to get a system up quickly - but I would try to figure out how I was going to add it later, and include some provisions for it - even it it's just a couple extra tee fittings that are capped off for now...

As to the efficiency question - what sort of LP boiler do you have now? Is it a mod-con style high efficiency unit, (usually wall vented) or a traditional plain boiler? It makes a difference, as the mod-cons don't lose a lot of heat as they rely on a fan for combustion air flow, and have little or no airflow through the boiler if not actually burning... OTOH, you can lose a lot of heat with a traditional boiler, as it will set up a draft flow through the combustion chamber just like it was burning, and pull a lot of heat out of the burner HX...

I think the control part is relatively simple - especially on the parallel setup - essentially design whatever controls are needed to make the wood side deliver heat into the system - then add a double pole relay triggered by an aquastat on the wood side, that sends the house thermostat call for heat to the wood side if it's hot, and the LP side if it isn't...

The close space tee option would use the same approach, but is a little trickier as you have to control both the wood side and the circ for the LP side, while keeping the LP burner from firing...

Gooserider

Yes I should be able to cut the 1-1/4 pex supply and return from outside the back wall of my shop and add a few tees.
The eko boiler will be inside my shop and I,ll put my storage outside directly behind the eko.

Sounds reasonable, just note that outside storage needs REALLY good insulation...

If I can tee in above the air extractor to left of the copper union and before the dhw p/p on the discharge side of the lp boiler without too much trouble, I will do the parallel setup.

That would work, I think...

Yes my lp boiler is a modulating condensing Buderus gb 142 .

I guess I should be able to put this relay and aquastat in the house beside my lp boiler on the supply from the eko?

Not really - it needs to be on the storage tank, or the boiler if skipping storage - if you have it on the house end, if the lines cool down because you had the heat calls satisfied for a while, you might get a "false cold" where the aquastat on the house end signals that it's cold and fires the LP boiler even though the wood setup in the shop is still hot.... However if you drop a length of conduit in the trench with your PEX, and run a chunk or two of CAT5 Ethernet cable through it, that will be plenty to carry the signal...

Another thing that im not sure about is if I can run water with treatment in it through my lp boiler.

Cheers Huff

Unless you are doing some really strange treatment I'd be surprised if you couldn't... Check w/ Buderus to be sure, but most boilers allow antifreeze to be used, and the water treatment should be less of a problem than that...

Gooserider

 

[huffdawg]

It says in the lp boiler manual not to add treatment additives or glycol to the boiler water . It does not give reasons as to why .

anyone on here have any experience with buderus mod con gas boilers.

I guess if I cant use treatment in it ,I might have to incorporate a plate type heat exchanger into my EKO addition to the system

Huff

 

[Gooserider]

It says in the lp boiler manual not to add treatment additives or glycol to the boiler water . It does not give reasons as to why .

anyone on here have any experience with buderus mod con gas boilers.

I guess if I cant use treatment in it ,I might have to incorporate a plate type heat exchanger into my EKO addition to the system

Huff

Must say I'm surprised... Again, I would say talk to Buderus - or hopefully one of our experts will be able to better help... It may also depend on what kind of treatment you are talking about - I'm not an expert on boiler chemistry by any means, but it seemed like there were some really strange brews that some places wanted you to add, and they might be trying to discourage those - but I can't see what the issue would be if just doing something like adjusting the water pH, that didn't put a lot of strange stuff in the water...

Alternatively, why are you wanting to treat the water in the EKO side of the loop any way? I haven't heard anything that said an EKO "required" treatment, other than to adjust for proper pH and the like...

Gooserider

 

[huffdawg]

This is what I found in the eko manual ,it doesnt say I have to use any treatment. The boiler package I bought from cozy heat comes with some treatment so I assumed the boiler needed it.

Filling the Boiler and Heating System.
Plain water is the recommended fluid for filling the EKO boiler and system it is connected to. The
easiest way to fill the boiler and heating system is through a regulator connected to the home’s domestic
water supply. The regulator steps the pressure down to 12 psi, so that the boiler can be filled
at the appropriate pressure. This connection to the home water supply can be left open or closed
with a manual valve after the system is filled. The advantage to leaving it open is that any water lost
is immediately made up and the system stays full of water at all times, including occasions when the
pressure relief valve opens. The disadvantage to leaving the water connection open is that tap water
contains oxygen, which will corrode the boiler and other components over time if enough oxygen is
routinely let in, say by a leak.
If the use of glycol is desired for freeze protection, be sure to use non-toxic hydronic heating system
antifreeze, available from plumbing and heating supply outlets. Follow the directions carefully. The
use of automotive glycol is not recommended, in part because it is toxic and can present a serious
public health risk under some circumstances. For that reason, it is against code to use automotive
glycol in hydronic heating systems connected to a public water supply.

 

[in hot water]

That's and aluminum block boiler. There have been some failures of these and other aluminum block boilers related to the treatment or glycols used. If you use glycol it must be an AL type and I would highly recommend using a good name brand. Stay away from the low cost brands even if they claim to be aluminum "friendly. Rhomar builds an excellent cleaner, conditioner and glycol for aluminum and multi metal boilers. Rhomar is recommend in several of the boiler manufacturers installation manuals.

Be aware Al glycol, properly formulated is very expensive. Rhomar has 35 different components blended to build a fluid that works with all metals, especially aluminum.

If the GB will tie into storage or a large fluid volume system I'd be tempted to isolate the GB from the rest of the fluid, with a HX to lower the cost and amount of treatment you need. All boilers should be cleaned and flushed in my opinion, with a good hydronic product, but it is more critical in aluminum block boilers. Same with the water quality.

hr

 

[huffdawg]

So what would be the consequences of not using any treatment in the storage and eko boiler.

I dont think freezing the eko will ever be a problem.

Its the corosion end of it that worries me ,although I think we have good water here.

 

[Gooserider]

I don't know for sure, as I'm not familiar with the Al block heaters - but I know it is usually not a good idea to mix Al with other metals in a wet environment, as Al is very prone to dissimilar metals corrosion. I would definitely want to talk to an expert about the wisdom of combining an Al block boiler and a steel boiler (and likely some copper) in the same system, and how best to prevent any harm from coming of it...

Gooserider

 

[huffdawg]

I finally got caught up for a bit with the hearth postings, and was able to do a bit of rough drawing with my CAD program - and created these rough drawings to show a couple of generic hookups... As I find time, I will keep working on doing other designs along the same idea - you may see these drawings fairly often...

The house load, wood boiler, and fossil boilers are identical in both drawings, the only thing that changed is the way they are connected.

I think I have the wood boiler set up right (in one of the many ways it can be done) but there is nothing special about that boiler configuration, any way of hooking up a boiler that has a supply and return coming out would work. You could also substitute the pressure side of an OWB or Garn HX - the same idea applies.

Similarly, the house load is very generic, I just slapped a DHW indirect tank and a few different styles of radiation together to give the general idea...

In the first drawing the two heat sources are in parallel, and are essentially independent of each other. Whichever one is chosen on a call for heat turns on it's pump and circulates through the house load - Again this is very generic - the pumps could also be constantly running temperature controlled, the basic idea stays the same. The flow check in each pump (which could be a discrete component instead) prevents flow through the unused circuit. (In theory it might also be possible to have both heat sources running at the same time, though this would be unusual)

The second drawing uses closely spaced tees to connect the wood boiler into the fossil boiler - house load loop. The pump for the fossil boiler (P3) will run on any call for heat (or again could be an always on pump) so it MUST be able to run without firing the fossil boiler. As I understand the theory of closely spaced tees, you could actually put them any where on the loop that is a main trunk, not just where I have them drawn. If the storage is hot P2 also runs to inject hot water into the loop through the close spaced tees. If the storage isn't hot, the boiler fires and everything works like the wood side wasn't there.

Gooserider

Hi GR. Im just trying to make up a list for fittings for the connection of the heat transfer lines to the lpg boiler .
I will be doing it as per drawing # 1 . Is there anything else that needs to be plumbed in to the near lpg boiler connections im putting in.

Thanx huff

 

[Gooserider]

I finally got caught up for a bit with the hearth postings, and was able to do a bit of rough drawing with my CAD program - and created these rough drawings to show a couple of generic hookups... As I find time, I will keep working on doing other designs along the same idea - you may see these drawings fairly often...

The house load, wood boiler, and fossil boilers are identical in both drawings, the only thing that changed is the way they are connected.

I think I have the wood boiler set up right (in one of the many ways it can be done) but there is nothing special about that boiler configuration, any way of hooking up a boiler that has a supply and return coming out would work. You could also substitute the pressure side of an OWB or Garn HX - the same idea applies.

Similarly, the house load is very generic, I just slapped a DHW indirect tank and a few different styles of radiation together to give the general idea...

In the first drawing the two heat sources are in parallel, and are essentially independent of each other. Whichever one is chosen on a call for heat turns on it's pump and circulates through the house load - Again this is very generic - the pumps could also be constantly running temperature controlled, the basic idea stays the same. The flow check in each pump (which could be a discrete component instead) prevents flow through the unused circuit. (In theory it might also be possible to have both heat sources running at the same time, though this would be unusual)

The second drawing uses closely spaced tees to connect the wood boiler into the fossil boiler - house load loop. The pump for the fossil boiler (P3) will run on any call for heat (or again could be an always on pump) so it MUST be able to run without firing the fossil boiler. As I understand the theory of closely spaced tees, you could actually put them any where on the loop that is a main trunk, not just where I have them drawn. If the storage is hot P2 also runs to inject hot water into the loop through the close spaced tees. If the storage isn't hot, the boiler fires and everything works like the wood side wasn't there.

Gooserider

Hi GR. Im just trying to make up a list for fittings for the connection of the heat transfer lines to the lpg boiler .
I will be doing it as per drawing # 1 . Is there anything else that needs to be plumbed in to the near lpg boiler connections im putting in.

Thanx huff

Well obviously I drew a "generic" house, so you will need to pick the fittings and pipes that meet your exact setup. Probably the only really big thing that isn't in the drawing is an expansion tank - you probably already have one for the fossil boiler, but you will need to add an additional tank, or replace the one you have with a bigger one (MUCH bigger if running pressurized storage) to allow for the increased system volume - I think I have links in the tidbits sticky on resources to figure the appropriate size - the big thing you will need to know is how much more volume you will be adding, including both the boilers and storage, and the piping itself.

The other thing I left out is any of the "trim" plumbing - purge valves and various isolation valves to allow servicing pumps and such, plus things like crud filters and air separators... I feel like a system should have at least one or two crud filters in various places, and air separators or other equivalent items at the boiler outputs and any other high points in the plumbing lines.

Gooserider

 

[huffdawg]

I have an expansion tk on the existing system.
I also have one that came with the Eko along with a taco 007 circ.p/p,air seperator,danfoss mixing v/v and a honeywell aquastat.
As far as elbows , tee's , reducers and such I think I got it figured .I will add acouple of crud filters also
I will be adding storage after get the boiler up and running .
I guess a emergency heat dump will be good idea?

Thanx Huff.

 

[Gooserider]

I have an expansion tk on the existing system.
I also have one that came with the Eko along with a taco 007 circ.p/p,air seperator,danfoss mixing v/v and a honeywell aquastat.
As far as elbows , tee's , reducers and such I think I got it figured .I will add acouple of crud filters also
I will be adding storage after get the boiler up and running .
I guess a emergency heat dump will be good idea?

Thanx Huff.

You should still do the math to make sure that you have enough expansion volume to operate w/o popping the PRV... Yes, some kind of heat dump is a good idea - usually involves an open on rise aquastat, an Automag control valve, and whatever plumbing you make the zone from...

Gooserider