Help!? Design my install (heat dump, pumps, storage)

[sghickey]

Hello, I am new to the boiler adventure and my new glenwood 7050 arrives today. I have been reading and researching for weeks and I believe I have my head wrapped around the install for the most part. There are a couple of questions I would love some feedback on. and if some of you are willing, some ongoing feedback as I work my way through this setup. I want to attack this install myself as much as I can, so that I am very familiar with my own how to and such. I appreciate in advance any and all feedback. I will begin posting pics as I dig in..

My set up...
Glenwood 7050 in garage, vented through roof via pre-existing chimney.
half inch 6 way manifold to service 5 zones ( 1 inch inlet to manifold, .5 inch legs)
5x taco 007 pumps ran inline post manifold to each zone
zone 1 - water to air exchange for forced air unit
zone 2 - Domestic hot water
zone 3 - panel style radiator in basement to creat a basement zone seperate from the forced air
zone 4 and 5 - panel style radiator in kids rooms on 3rd floor to supplement
note: currently no pump pre manifold although I have a taco 1 / 6th horse pump, but I am hoping to reserve this for the guest house run in the spring.

In case it matters,
The Glenwood 7050 will heat 6000 sq ft but for now we are working with just the main house at +/- 4000 sq ft
( the guest house and shop will be projects for next year)
The loops for zone 1,2, and 3 will be apprx 20-30' total loop distance
zone 4 and 5 will be 30 - 40' total loop ( zone 1-3 is in basement nearly directly below the boiler placement, and zone 4 and 5 are upstairs above the garage/ boiler placement) 3 stories including basement, boiler and garage on middle/main level

Plannning on a whole home generator once this install is complete as well as solar back up next year, so...... a "power out " heat dump/ circ/ heat my home whenever plan is covered I believe.

My questions.

Pumps:
Because my loops are minimal length, my thought was to only have pumps on the legs of the manifold pulling heat for each zone as needed. in other words, no pump on main supply line. Is this a reasonable thought?

Heat dump: Based on the above thought, What would be the best way to create a heat dump without adding another pump on main supply line if that is even possible

Heat dump: Can someone explain the plumbing flow on the heat dump? is it a pass through or bypass with a diverter or.......

Storage: why storage?

Zone 4 and 5: Kids bedrooms share a wall and are basically directly above the garage/ boiler placement. Should I run one line to the closet inbetween and then have a 2 way manifold with thermostats to open/close valves on the legs ( one pumps pushing both) or run each seperately from the main manifold and each have their own pump and thermostat etc...

Im sure I will have more questions and many trips to lowe's/ home depot but im looking forward to this process. Also, I intend to do nearly all of this install with pex as opposed to copper initially. this way I can make adjustments or fix my trial and error items without too much headache. After everything is done and Im ready to set my install in stone ( or copper ) I will take on the task of replacing the pex with copper a few legs at a time.

 

[sghickey]

more questions?
Would it be better to put in baseboard style radiant heaters for basement and kids rooms, or the panel style. If it is simply preference based on aesthetics then Ill let the wife pick em out.

also, can I use a panel style radiator in my garage as the heat dump? will that disperse enough heat? plus it would heat up the garage some.
thanks

 

[GENECOP]

What will you be burning...the 7050 is a multi fuel unit...

 

[GENECOP]

Also Thoroughly read the sticky subject at the top of the forum, there is a lot of detail plumbing flow, and the best simplest designs... Search STORAGE, there are literally hundreds of posts that discuss it and it's benefits, welcome aboard...

 

[sghickey]

Burning wood only.
I will and have been reading everything I can get my hands on . Thanks. First things first. I have to get it off the pallet.

 

[huffdawg]

more questions?
Would it be better to put in baseboard style radiant heaters for basement and kids rooms, or the panel style. If it is simply preference based on aesthetics then Ill let the wife pick em out.

also, can I use a panel style radiator in my garage as the heat dump? will that disperse enough heat? plus it would heat up the garage some.
thanks

Its more than just aesthetics ,panel rads you can utilize lower temp water and yes you can use them for a heat dump. Just has to be sized properly

 

[huffdawg]

Best thing you could do is post a working sketch or drawing of your design intentions . Lots of good help on here . The guys will offer lots of constuctive criticism. Gotta luv install pics.

 

[sghickey]

i am trying to figure out taco hss software to get a good working model. I will try to put up something soon, it just might not be incredibly detailed yet.
I plan to be pushing close to 180 degrees due to the use of my forced air heat exchanger, so the water in the radiator ( baseboard or panel ) will be a higher temp either way I think. Im hoping to zone every little thing i can, and although this might be overkill as opposed to running the radiators in series, it gives me the ability to isolate every zone down the road for adjustments or repairs etc. ( if one pump goes out, then only one room is cold etc...)
diagram coming soon

 

[maple1]

I would go big on the forced air exchanger, design for cooler water if possible. Some will put in the biggest that can physically fit. That will alleviate the need to maintain 180 all the time - a big factor if storage is being considered.

 

[sghickey]

ok this is a somewhat crude schematic of my initial plans. this represents the boiler and water flow but doesn't show each and every zone. however, Im not as concerned for now about each appliance, more focused on the boiler and pump set up initially. I know its all connected but if i could get some feedback on this first. I will then focus on installing each zone with thermostats etc. after ( see attachment )

 

[sghickey]

I would go big on the forced air exchanger, design for cooler water if possible. Some will put in the biggest that can physically fit. That will alleviate the need to maintain 180 all the time - a big factor if storage is being considered.

Well, storage is a possibility but definately a next fall project if I do. I will inquire as to the benefit vs. additional cost etc. when I get this install mostly behind me
water temp: I Plan to fidget with the water temp a bit as you are not the first to recomend something other than 180 for various reasons and of course Ive seen plenty statements about 180 for air handlers vs. radiators and domestic hot water
I have the largest exchange that will physically fit in the air handler. and Have an hvac pro coming to install that portion for the sake of inexperience with sharp objects. ( seriously though im hiring that out )

 

[sghickey]

Best thing you could do is post a working sketch or drawing of your design intentions . Lots of good help on here . The guys will offer lots of constuctive criticism. Gotta luv install pics.

here it is so far

 

[sghickey]

Ok everybody...

- is my schematic viewable?
based on the schematic, please notice that there is no circ pump on the boiler out' untill the zone lines split from the main out/supply. In my head I think this would work because my distances are so moderate on the zone loops. ( everything i need to heat is on the same side of the house either directly upstairs or directly downstairs. thoughts?
- also I believe I need a zone controller so I'm looking at a taco 6 zone ( see below for amazon i.d. )
my parts are starting to arrive from various supply houses etc
- I plan to use a heating element in the garage ( where the boiler is ) on the main return as a heat dump. either a panel style radiator with a zone valve that sends the return water through the panel if the water gets too hot or a hydronic heater with a fan that is automatically in the loop but the fan kicks on when the temp gets hot. ( either of these would also provide heat in the garage but the hydronic heater with fan could be made to turn on manually if I want to heat the garage etc....) thoughts?

50,000 BTU Hanging Unit Heater - Single Speed Fan w/Thermostat and Air Vent




TACO 6 ZONE VALVE CONTROL WITH HOT WATER HEATING SYSTEM CIRCULATOR PUMP RELAY AND TRANSFORMER



White Horizontal Designer Radiator Heater

 

[maple1]

Couple thoughts:

-Heat dump should be able to handle a power outage situation (that is likely the most common occurance that would need heat dumped). I.e., work without a pump, by convection. So the emitter should be directly above the boiler (directly tied to the top of the boiler, not on a return line), with a direct return path back to the bottom of the boiler, and use a normally open zone valve at the boiler exit to regulate flow. Then on a power outage, the zone valve will open, and flow will convect around the loop. The zone valve should also be tied to an aquastat that would break on temp rise, then it would work for either a power outage, or a power on overfire situation. And the end switch in the zone valve should also be wired to start a circ pump when the valve opens. Mine is adapted to use my upstairs radiator zones for the emitter part, but how or if you can adapt to one of your existing zones depends on your layout. Some just hang a few lengths of fin tube right above their boiler - a big old cast iron rad on the next floor above the boiler could also be used as a dump zone and also a normal heating zone, if plumbed right.

-Might be a matter of preference, but I would not use a pump for each zone. I would use a zone valve for each zone, and one circ pump - a variable speed ECM pump, such as a Grundfos Alpha set to run in constant pressure mode. That is a super sweet pump and really shines when used in a varying load situation like you have here. And will reduce your power consumption considerably.

-Do you have return temp protection planned? Wood boilers suffer if return temps are consistently below 140 or so.

 

[sghickey]

Couple thoughts:

-Heat dump should be able to handle a power outage situation (that is likely the most common occurance that would need heat dumped). I.e., work without a pump, by convection. So the emitter should be directly above the boiler (directly tied to the top of the boiler, not on a return line), with a direct return path back to the bottom of the boiler, and use a normally open zone valve at the boiler exit to regulate flow. Then on a power outage, the zone valve will open, and flow will convect around the loop. The zone valve should also be tied to an aquastat that would break on temp rise, then it would work for either a power outage, or a power on overfire situation. And the end switch in the zone valve should also be wired to start a circ pump when the valve opens. Mine is adapted to use my upstairs radiator zones for the emitter part, but how or if you can adapt to one of your existing zones depends on your layout. Some just hang a few lengths of fin tube right above their boiler - a big old cast iron rad on the next floor above the boiler could also be used as a dump zone and also a normal heating zone, if plumbed right.

-Might be a matter of preference, but I would not use a pump for each zone. I would use a zone valve for each zone, and one circ pump - a variable speed ECM pump, such as a Grundfos Alpha set to run in constant pressure mode. That is a super sweet pump and really shines when used in a varying load situation like you have here. And will reduce your power consumption considerably.

-Do you have return temp protection planned? Wood boilers suffer if return temps are consistently below 140 or so.

ok, i have plans to put panel radiators upstairs in the bonus room/ boys play room. I suppose that could be the convection heat dump?
I also thought I would back up power with generator right away, then eventually run this system off solar. so heat dump due to power outage will only be a concern for this first season.

I assume return protection is a concern if there is potential heat loss below 140? I hadn't thought about it mostly because my loops are very short in comparison to some set ups i have seen and i don't think my temps will bottom out like that, but if I could easily be wrong. wht is the best way to offset the return temp?

I had toiled over the one pump with zone valves vs one pump per zone thing for a while and it seems electricity usage would be less with 5 intermittent tiny pumps going only during heat call, vs one big pump running all the time. but i was simply speculating so please enlighten me here, I can switch plans at this point and return the small pumps if need be. Also it seemed there might be some benefit to having multiple pumps because if 1 of the pumps goes out, then only one zone gets cold, with one big pump... if it goes out, the whole system is useless untill i replace the pump..
thanks for responding to my thread im trying to wrap up some of my major questions so I can get started with my layout etc..

 

[maple1]

The Alpha 15-55 isn't a 'big' pump. Actually don't think it's much 'bigger' than the 007 - while using less electricity. And it varies speed depending on how much flow is being asked of it. Have you done any head loss/flow calcs on your zones?

You might be able to use the rads upstairs for dumping, but it depends on layout. The hot water wants to have a straight up path from the boiler to the emitters. And you don't want any obstructions in between or in the loop, like other zone valves or check valves. Back up power with a generator is good - if you are absolutely certain it will work exactly as it will be needed when your back is turned. The power going out when there is a fire in the firebox & nobody home can make for a hairy situation in short order - I would not depend solely on a generator, redundancy is key here. I have a NO zone valve setup to dump upstairs, plus water can convect to storage, plus a big UPS I can plug my boiler circ into if I'm going out, plus a generator I can dig out & plug into.

 

[sghickey]

The Alpha 15-55 isn't a 'big' pump. Actually don't think it's much 'bigger' than the 007 - while using less electricity. And it varies speed depending on how much flow is being asked of it. Have you done any head loss/flow calcs on your zones?

You might be able to use the rads upstairs for dumping, but it depends on layout. The hot water wants to have a straight up path from the boiler to the emitters. And you don't want any obstructions in between or in the loop, like other zone valves or check valves. Back up power with a generator is good - if you are absolutely certain it will work exactly as it will be needed when your back is turned. The power going out when there is a fire in the firebox & nobody home can make for a hairy situation in short order - I would not depend solely on a generator, redundancy is key here. I have a NO zone valve setup to dump upstairs, plus water can convect to storage, plus a big UPS I can plug my boiler circ into if I'm going out, plus a generator I can dig out & plug into.

so the alpha pump you speak of is 1/16th horse, the ones i have are 1/25th horse per zone. i also have a taco 1/6 horse pump that obadiahs recomended as the circ pump for my boiler. However, I was thinking I would save the bigger taco for the guest house run or the shop run when I get around to digging that trench.

another question for you all.... I have seen bits of talk about special solution in the loop instead of regular water. do I care about this?
thanks

 

[Bob Rohr]

All the pumps should be sized to the load you are connecting to them. Most common hydronic pumps have multiple speeds to help dial them in.

I agree one 40W ECM pump may be enough to pump all those zones. With those 5 you have close to 400W, as shown! Really no need to use that much power to pump hydronics these days.

Return temperature is always a good idea, most solid fuel boiler piping schematics show that detail.

If you want to back up a bit more, ideally every room should have a heat load calculation performed.

Then the heat emitter type and size gets selected to cover that load requirement.

Then the piping and pumping gets determined by the load and emitter selection.

You are kind of jumping in mid stream without that important data?

Panel radiators are my favorite also. They can operate at lower temperatures, are easily zoned with TRVs requiring no power, and the emit heat by convection and radiation, nice to be around

I'd size the heat emitters for the lowest possible temperature. 160F supply, maybe even 150 could work as long as you have enough best emitter and protect the boiler from extended cold run periods. The fan coil should have a spec sheet showing BTU/hr output at various supply temperatures and flow rates, same for fin tube baseboard.

 

[sghickey]

All the pumps should be sized to the load you are connecting to them.

Bob,
Thank you so much for chiming in. I truly have never done anything like this before so all input is appreciated. If I may ask for clarification on a few points....?

1. I believe i understand you statement concerning Heat loan calculations, then sizing the pumps to that data. is there a good guide to walk me through running those numbers or a known formula? the basement might be tricky because I have plans to have the forced air heating the basement but since the existing ductwork isn't zoned the thermostat cuts the heat off now when the main floor is 72 but the basement may only be 62 and therefore in new system i will zone the basement with a panel radiator to get me the rest of the way to 70 ish degrees in the basement

2.you mentioned zoning with " TRV's" can you tell me what this stands for or give a link or ? I assume its a zone valve but not positive

3. you said "
I'd size the heat emitters for the lowest possible temperature. 160F supply, maybe even 150 could work ( I was under the impression i need to hit my air handler exchange closer to 180 degrees, wont my forced air fan run longer to heat my home ( main floor) if the water temp is lower? ) as long as you have enough best emitter and protect the boiler from extended cold run periods. The fan coil should have a spec sheet showing BTU/hr output at various supply temperatures and flow rates, same for fin tube baseboard. Can I not just put bigger than i think Ill need in the radiator application? so long as my boiler will cover the btu's. ( it will push 200,000 btu's ) wouldn't my zone valve just shut sooner if the bigger radiator puts out heat with 180 degree water etc.. [/QUOTE]

 

[maple1]

I'd size the heat emitters for the lowest possible temperature. 160F supply, maybe even 150 could work ( I was under the impression i need to hit my air handler exchange closer to 180 degrees, wont my forced air fan run longer to heat my home ( main floor) if the water temp is lower? )

That's where the sizing comes in. Bigger exchanger = more BTUs, all else being equal. Oversized HX would make up for the lower water temp.

as long as you have enough best emitter and protect the boiler from extended cold run periods. The fan coil should have a spec sheet showing BTU/hr output at various supply temperatures and flow rates, same for fin tube baseboard. Can I not just put bigger than i think Ill need in the radiator application? so long as my boiler will cover the btu's. ( it will push 200,000 btu's ) wouldn't my zone valve just shut sooner if the bigger radiator puts out heat with 180 degree water etc..

You just answered the air handler thing right above.

Another aspect of a variable speed constant pressure ECM pump such as the Alpha - they can be throttled down to slow flow, as needed. Unlike an ordinary circ, which will just try to keep pumping water at the same speed/amount no matter how much it is restricted or how much head it sees, an Alpha will vary it's speed to match the pressure it is sensing. With my 4 zones - if one zone opens, it pumps 2gpm. Another zone opens, it speeds up to 4gpm. (Rough approximation). All by itself. You don't even have to wire it to a control, you can just plug it into an outlet & it can sense a zone valve opening & ramp itself up. I think - that's what I read but haven't tried it. Mine is wired to zone valve end switches the same as the 3 speed 15-58 it replaced.

So, if you really wanted to go bullish & simplify the thinking & calculations - you could MAYBE just put in a whole bunch of radiation or emitters (enough so that you know you've got more than enough), then vary the flow through the zones to balance out the heat output by throttling with ball valves & let the Alpha settle to the flow you need. That might lead though to ends of long zones not getting enough heat while the first parts of the zones are too warm. Not so much an issue with short zones.

TRVs sound great - never heard about them until it was way too late for me to use them. Google them up. Sort of a thermostatically controlled zone valve - works to maintain a more constant but lower temp flow, best used with low temp emitters like panel rads or cast iron rads. Some on here have systems that pump all the time, but the TRV regulates the temp of the water thru, or more like how much goes through. Very constant comfortable heat.

 

[stee6043]

One other consideration on the pump topic is the fact that having 5x taco 007's operating at the same time would create a lot of pumping force. I can't imagine the kinds of weird flow's you might get if all of your zones activated at the same on super-short loops. You could find that you'll pull water through that boiler with such velocity that you don't get the heat transfer you need to actually heat the water effectively. 3-speed Grundfos pumps were one of the best enhancements I ever made to my system. And they almost always ran on low.

One non-pump related thought - generally you can't legally install/operate a wood fired appliance in a garage. If you're planning to have this install permitted and inspected, this will likely be a non-starter. If you're going without the permits you'll want to take special care to ensure you separate fuel sources properly, especially since you're kids rooms are above the garage. If you penetrate the ceiling to access those rooms make sure you use proper fire barrier when doing so. You'll want to go over the top on safety if you're going to install a non-code compliant system. If you ever have a problem and, heaven forbid, a neighbor kid is having a sleep over - your umbrella policy may not be enough to cover the loss.

I'd personally consider installing a sprinkler head or two in the area of the boiler if I were going to do this. I'd also make sure you have a smoke hood of some sort installed above the boiler. I can tell you from experience smoke can find it's way between floors even where there are not vents. Your kids rooms may well smell perpetually of smoke during heating season if you don't come up with a powered vent of some sort for loading times.

 

[sghickey]

"That's where the sizing comes in. Bigger exchanger = more BTUs, all else being equal. Oversized HX would make up for the lower water temp."
So I get that part but on my forced air, there is a limit to size. I will buy oversized panel radiators and play with water temp/ consult a hvac freind of mine for some btu calculations etc.

3-speed Grundfos pumps were one of the best enhancements I ever made to my system. And they almost always ran on low.
so do you think one pump will do the trick? for 5 zones including domestic hot water? I have seen some systems with a return pump etc..???

One non-pump related thought - generally you can't legally install/operate a wood fired appliance in a garage. If you're planning to have this install permitted and inspected, this will likely be a non-starter. If you're going without the permits you'll want to take special care to ensure you separate fuel sources properly, especially since you're kids rooms are above the garage. If you penetrate the ceiling to access those rooms make sure you use proper fire barrier when doing so. You'll want to go over the top on safety if you're going to install a non-code compliant system. If you ever have a problem and, heaven forbid, a neighbor kid is having a sleep over - your umbrella policy may not be enough to cover the loss.
1. Obadiahs told me I will need to enclose the boiler with a framed and drywalled room/ closet to meet code for the simple fact of keeping combustibles away from the radiant heat of the boiler itself. ( in the plans )
2. My house ( we moved here in sept this year) apparently had a wood stove in the dining room which shares a wall with the garage. although the wood stove is not there anymore ( previous owner removed) the chimney is still in tact and It looks like i will need about 6 feet of double wall to connect. seems like an easy part of the process . p.s. home and chimney is only 7 years old. included pic ....
3. in fact, where I live there is no permit necessary. I don't plan to skimp in the safety department and in fact this thought process has made me think of putting in a heat detector and probably some additional smoke detectors in areas with potential danger connected to my home security system. and a sprinkler head is not a bad idea either.
I really appreciate you bringing that up, because burning my house down wasn't in the forefront of my mind when I started this process. safety first.

So Im going to send back the 5 pumps and order 1 or 2 of the alphas based on the variable speed features and your recommendations. I also have a friend who is a video hobbyist and we are going to make a series of start to finish videos walking through this whole process from start to finish. I have seen videos online but they are either not comprehensive or they are professionals speaking in professional terms. I want to create a guide from start to finish for the inexperience but handy do it yourself fella....
I wouldn't have any issue crediting you guys if you like, " This info came from John Doe in Michigan" etc. I would just need a first name and general location and boiler type if you like too... Keep the info coming and please keep an eye on this thread as I will post pics, links to vids and plenty more questions to come...

 

[sghickey]

quick question.: which one do I want....

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[stee6043]

"That's where the sizing comes in. Bigger exchanger = more BTUs, all else being equal. Oversized HX would make up for the lower water temp."
So I get that part but on my forced air, there is a limit to size. I will buy oversized panel radiators and play with water temp/ consult a hvac freind of mine for some btu calculations etc.

3-speed Grundfos pumps were one of the best enhancements I ever made to my system. And they almost always ran on low.
so do you think one pump will do the trick? for 5 zones including domestic hot water? I have seen some systems with a return pump etc..???

One non-pump related thought - generally you can't legally install/operate a wood fired appliance in a garage. If you're planning to have this install permitted and inspected, this will likely be a non-starter. If you're going without the permits you'll want to take special care to ensure you separate fuel sources properly, especially since you're kids rooms are above the garage. If you penetrate the ceiling to access those rooms make sure you use proper fire barrier when doing so. You'll want to go over the top on safety if you're going to install a non-code compliant system. If you ever have a problem and, heaven forbid, a neighbor kid is having a sleep over - your umbrella policy may not be enough to cover the loss.
1. Obadiahs told me I will need to enclose the boiler with a framed and drywalled room/ closet to meet code for the simple fact of keeping combustibles away from the radiant heat of the boiler itself. ( in the plans )
2. My house ( we moved here in sept this year) apparently had a wood stove in the dining room which shares a wall with the garage. although the wood stove is not there anymore ( previous owner removed) the chimney is still in tact and It looks like i will need about 6 feet of double wall to connect. seems like an easy part of the process . p.s. home and chimney is only 7 years old. included pic ....
3. in fact, where I live there is no permit necessary. I don't plan to skimp in the safety department and in fact this thought process has made me think of putting in a heat detector and probably some additional smoke detectors in areas with potential danger connected to my home security system. and a sprinkler head is not a bad idea either.
I really appreciate you bringing that up, because burning my house down wasn't in the forefront of my mind when I started this process. safety first.

It sounds like your dealer was mostly on the right track but he left out an important piece. The closet you build would need to have an exterior door and cannot be accessed from within the garage (if I recall correctly). It's a bit more involved than building a closet. Some folks here have done it, for sure. But if I were faced with that much construction I'd probably choose to build an "extension" on the outside of the garage rather than eat up garage floor space. Cost would be almost the same?

On the pumps I do think one would be enough based on how short your loops are but you really need to consult their documentation to confirm your loop length and elevation change fit within the allowable head on a given pump model. I went with the cheaper (non-Alpha) three speed pumps and was very pleased. You're looking at the higher end rigs above, which is cool too.

 

[sghickey]

"It sounds like your dealer was mostly on the right track but he left out an important piece. The closet you build would need to have an exterior door and cannot be accessed from within the garage (if I recall correctly)." any thoughts as to why it makes a difference....? I have a very deep garage 26 foot i think, but my house is sided with stone... probably not gonna cut into the stone..

Also, does it make a big difference if I get the one with the cord to plug direct into an outlet or one with the terminal box.?
will it performance or feature?