Radiant Heat not Heating

Tom_133

One more pic.

Smitty



I can't see the return pipe behind the black box

Rich_49

Winter

approaching . I would say that there are some of the brightest minds in the industry right here .  I would be willing to look at the room by room and give calcs , possibly some others would do the same . You , my friend should take advantage of the assistance offered here . If you are willing to tear down and redo the information will be invaluable to you .  Some of the rooms that are done may not meet the criteria to be on the same zone ( btu sq ft req , use pattern , similar finish floor) that some of us know about . Be sure to include your design day criteria . Do the upstairs too and basement , there may be a solution to your problem . Type of windows and doors also .

CMadatMe

That Will Work For My Experiment

In your original post you have the 1st floor as 1,000 sqft - I see 4 loops in total in the picture. Are there 2 loops for the 1st floor and 2 for the second? What was the heat loss for just the first floor and what are the finish floor surfaces? 3/4" Oak?

CMadatMe

Smitty Experiment

Ok. You said your 1st floor was 1,000 sqft and your total heat loss is 37,000 for the entire house. I used 16,000 btu/hr for a 1st floor loss and treated the entire 1,000 sqft as one open room. See attached! This is with 8" on center. Those flimsy plates might get you 10 degrees less water temp but I have double in the floor then what you have for tubing!!



In the end you don't have enough train track on your rail.. See experiment 2. This is where you should be not where you are..

Gordy

What it's showing

Is 5 loops of 3/4" for suspended tube, and 8 loops for 3/8" joist track plates.

This is only for one floor. You have 4 loops for 3 floors.



If you have no problem correcting the error, all is not a disaster on the main floor. Just add loops to get your 8" on center with plates the extruded omega type. You will lower your average water temp. Have more even heat across the floor.



This involves some repiping in the mechanical room to allow for the extra loops.



The basement is not a loss as you said that heated well.

smittyal06

Best

There is actually 2 loops per floor. 2 basement, 2 main, and 2 upper. It would be best to take out the 3/4" and run it all 3/8" correct? Is this also better then going 1/2"? What type of plates should I use? I still question this however. If I get the main floor run correctly and that is heating well, is this going to help at all with the upper level? That is why I posed the question of possible going forced air or radiant baseboards to help heat the upper floor from the main floor. I do not wish to rip out the ceiling on the main floor to fix the upper level if there is other options?

smittyal06

Heat loss numbers per room

Main floor heat loss: 23,801

bathroom: 1915

laundry: 1157

bedroom: 2416

kitchen: 3201

dining: 5007

living: 10103



2nd floor: 14052

bedroom: 5402

loft: 3282

office: 2334

bath: 3044



With adding loops to the main floor and it sounds like I should be creating different zones, is a zone just a loop? Also, the main floor has only 1 thermostat. Is that an issue with adding more loops or zones?

The main floor kitchen, dining, and living are basically one large room. There are no walls between these areas. It is just one large open area with lots of windows.

Gordy

Information

Okay so that means you have



2-350' loops in the basement

2-350' loops on main floor.

2- 280' loops on second floor.



Add leader lengths from manifold and back to those lengths.



This is provided they used 16" spacing through out.



You are only looking at a little over 4' of head in your loops at 1.5 gpm. If that's what the flow rate is. What size are the circs?

Gordy

Zoning

A zone can be what ever you want to make it.



Each floor could be a zone, or certain rooms.



In your case I would treat each floor as a zone.





If you can add enough base board, or panel rads on the second floor so they can run on the same water temps as the radiant it's an option.





Still need to know a few things Smitty

Circ size



Floor coverings



Btu output of heat exchanger



Back up boiler output.



Water temps you were running.

Gordy

I see

One pair of loops that is reduced down to 1/2" supply. Your trying to feed two 3/4" loops with 1/2" pipe. 1/2" will carry 15000 btus.

smittyal06

How

would I be able to run a baseboard on the second floor though  without having access to the piping?



The main floor is mostly hardwood. The bathroom and laundry are tile.

The second floor is mostly wood laminate. The bathroom is tile.

The boiler water temp was 170 degrees.

By circ size do you mean the pumps? They are Grundfos UPS15-58FC 1/25HP

Tom_133

Piping

Am I the only one here that thinks the header piping is extremely poor? I can't figure out why they piped it the way they did. I only see the zone pumps and nothing else pushing it through the plate exchanger (on the pressure side)and the electric heater. If that's the case the zone pump is pumping through long tube lengths and through the plate exchanger and because I can't see otherwise its also pumping through the electric boiler, seems like a serious lack of flow. Perhaps I'm not seeing it right or there a primary pump in the electric boiler.

Zman

Bingo!!

Tom,

You are correct.

It is great that we now have a heat loss calc we can now verify that the emitters are too small.

I am glad no one tripped over the 800 pound gorilla in the boiler room. It would be absolutely impossible for the system as piped to deliver the water correctly to the (theoretically) undersized emitters. The delta T is too high, indicating a flow problem. It may be that some additional emitters are needed. If this was new construction we would have added some. Why not fix the obvious stuff first.

Carl

CMadatMe

Not a Flow Problem

There are not enough train cars attached to the train engine to carry the btu/hr required to drive through the R-Value of the floor and over come the heat loss!!!!! The btu/hr is being sucked up, used and abused! Plain and simple.

Zman

System

Look at the picture on the post labeled "system" and please explain how it could possibly be working?

I don't disagree that emitters could use improvement. I think the first problem is obvious piping errors should be addressed before tearing apart the house .

High delta t indicates too much emitter for the flow or too little flow for the emitter.

Carl

 

smittyal06

Emitters

What are the emitters that you speak of?

Gordy

Boiler piping

And manifolds yes I agree its all lack luster. But at the same time you need to know if the emitters are going to work.....right?



1/2" pipe feeding 2 3/4 loops is a red flag also. Unless those loops need less than 7500 btus each.

smittyal06

Pump

Here is another photo. There is a pump sending the fluid through the electric boiler and the transfer plate. The electric boiler is turned off all season as we use the outdoor wood boiler.

Tom_133

Smitty

I realize the electric boiler is off when the wood boiler is on but the circ still pumps through it all the time. The boiler and the plate exchanger combined means a lot of restriction. But if you valved off the plate exchanger and still didn't get the heat I would say you have other problems. I don't like the non closely spaced tees separating the individual zones, the pump on the return after all the zones in respect to where the expansion tank is.

Gordy

Boiler head loss

That electro boiler has pretty low losses. Smitty can you verify size of boiler? Model #



Also heat exchanger size (output) brand so we can calculate some head losses in the mechanical room.



Also pump sizes/ brand.



3/4" copper can carry 42000 btus. So you are right there for your heat loss.





If the passengers (Btus) are all ready to board the train (boiler loop), and there are not enough seats, and track (radiant loop) to get them to their destination we have to redisgn.

Rich_49

I concur Gordy

Smitty if you owned the railroad and all the passengers that had to be at work at 8:30 took all the seats and got off at the first 3 stops out of a possible 12 stops you would add more seats for the people that had to be to work at 9:00 at the other 9 stops .

smittyal06

Sizes

The electric boiler is a Electro-Boiler Model EB-MS-15.

The heat exchanger is a SWEP B10THX20 / 1P-SC-S

The 3 pumps feeding the floors of the house are Grundfos UPS 15-58FC and the Blue pump placed to the left of the electric boiler is a Grundfos UP 15-42F.



I agree that more tubing needs to be added in order to provide better heat for the main level. My question still remains this. If I do this, will this leave more heat in the system for the upstairs? I know run on 16" centers the upstairs is not run properly either, however, I am not as willing to tear out the ceiling of the main level. So, would the remaining heat in the system be enough to heat the upstairs given the heat loss calculations and knowing there are only two loops upstairs run the same as the main level?

Gordy

Smitty

Your circs should be fine for the head they are pushing.



When you were using the electro boiler what temps were you running?



That's a three stage boiler. 51000 btu output.



Definitely repipe the supply/return manifolds with manufactured ones with flow meters. In doing this think about how many more loops you will run, and get the proper size manifold accordingly.

SWEI

Room by Room Heat Loss

will answer that question.

Gordy

If

You did your heat loss calculations correctly. Then yes your boiler will produce the required btus to heat the home. You just need to have an efficient amount of emitter to transfer those btus where they need to go, and that's to each room.



It does you no good to produce 51000 btus with only enough emitter to move 27000 btus. Gotta get them out of the mechanical room



Think of a conveyer belt. With btus on it going to various parts of your home.

smittyal06

Skematics

I know this is a very rough sketch. I have drawn the layout of new pex. I came up with 7 runs on the main level.

Bedroom: 250'

Living1: 250'

Living2: 260'

Bath: 290'

Dining: 280'

Kitchen/Laundry: 250'

Kitchen2: 275'



If you wouldn't mind taking a look at what I have.

Is going with 1/2' pex the proper material to go with?

Gordy

New layout

Smitty I assume you are leaving the 3/4 in place. These 3/4" loops will have to be repositioned to allow another run in each joist bay.



Will you be using extruded omega style plates, on the new loops?



Do the loop lengths you gave include leaders to the supply/return manifolds?



1/2" pex will be fine. At .7 gpm flow rate your head will be about 5.2'. At .6 gpm it would be 3.8 ' of head.



You still have to address what water temps you are using to calculate the proper flow rates.

smittyal06

Info.

I was going to take down the 3/4 inch and start fresh so all of the loops would be 1/2". Would you recommend using the 3/4" still?

I was not sure what plates to use. If that is what you recommend, that is what I will go with.

The loop lengths do include leader to and from the manifold.

I am not sure what you mean by head?

The water temps I used in the past were 175 degrees. Would you recommend staying with this or could they be lowered?

Gordy

Smitty

Honestly I would start from scratch. You can  find decent manifolds for 3/4" pex with flow control valves, but decent extruded plates for 3/4" pex not.. This is why you have the plates they have.



Its nice having flow control valves to dial in the flow rates you will know exactly what you are getting. Verses a pump curve, and unknown loop lengths you can get close.



In the end as I said if you leave the 3/4" pex. The runs would have to be moved in each joist bay to allow for the extra 1/2" loop your installing to get 8" on center. So basically your taking everything down except where it loops through the joist, and moving it one way or the other.



Using extruded plates will help lower water temps, and or increase output. Careful 180* is usually the limit for pex. The omega style plates grip the tubing better. (more contact area), and they are thicker (better heat transfer).



Head is the resistance the circulator has to overcome to create flow. The smaller the Dia. of the tube creates more head, and the higher the flow rate creates more head, and the longer the loop length creates more head. Think like water its lazy, and dumb. You have to tell it where to go, and how to get there. The easier the path is for it to follow the less energy it takes to get it there.

So keeping head loss reasonable helps you select a circulator as small, and energy efficient as reasonable to do the job. You have three 15-58's now YOu should be fine if your loop lengths are as you stated.

smittyal06

Cost and Quality

I know there are probably different qualities of pex pipe. The supplier I am working with will sell a 300ft roll for $172. However, Menards has a 300ft roll for $100. Is there going to be a major difference in going with the more expencsive stuff? Is Menards stuff junk and should not be used? Also the heat transfer plates. The picture I provided would these be good, or do you want one that wraps completely around the pipe? Does it matter if they are steel or alluminum? I have also got different opinions on plate placement. Should the transfer plates be butted up next to each other or a space between them? If a space, how much? Thanks.

Zman

Pex

You want to go with Pex-a with an O2 barrier or pex al pex

I am suspicious of  stamped steel plates. Do you have test data on them?

The last guy did this job cheap without a proper design. Do your homework so you do not follow him.

Carl

smittyal06

Agree

I would agree and that is why I am asking all of you. The Experts!

Zman

Plates

I realize that you are doing your research. I hope that did not come across wrong.

There a many companies selling products based on fictitious claims. I would not buy those plates without some back up data.

I realize that I am in the minority on this. I am still wondering if you have measured the delta t in your existing condition. Do you know the make and model of those mixing valves?

I agree with all who are think you may not have enough emitters. Your high delta t tells me there is also a flow issue.

Carl

Tom_133

Zman is correct

I really think the emitters are incorrect but the piping in the room is as bad if not worse.



Smitty, where are you located?

Gordy

steel plates

Smitty those are garbage compared to extruded aluminum plates.



Remember conduction is king with radiant heat. Extruded plates encompass 200 degrees of the tube for the plates total length. Now look at the steel ones. They encompass the tube 90 degrees intermitently for the plates length. Also aluminum is more conductive than steel.



Conduction from the tube to the plate, and from the plate to the subloor gets the btus where they need to be. at lower water temps.

Rich_49

Space between

emission plates . Yes you should have a space between them . An inch is usually good . They will expand as anything that gets hot does , they should have room to do so without affecting adjacent plates or putting undue stress on tubing .

smittyal06

Plates

You did not come across wrong at all. And I was serious when I mentioned I am asking the experts. I truly am taking everything you all provide to make this work.  I have removed all of the old piping and am ready to install new. That is why I am making sure now I am getting the correct piping and transfer plates.

Are these the type of plates you would use? They are Omega Aluminum. 18"x5" Not sure on gauge. If not, does someone have a good source for good plates that I should purchase. And maybe a picture so I know exactly.

smittyal06

Emitters

By emmiters are you talking transfer plates? I am located in Northern WI.

Zman

Plates

Here is what I like.

http://www.uponor-usa.com/~/media/Files/Product%20Documents/JoistTrak%20Cutsheet.aspx



Carl

smittyal06

Better

So these are better then the plates I pictured which completely surrond the tubing? Again, I am not questioning, just asking so I do it right. Does brand of tubing matter much as long as it has an oxygen barrier and is grade-a? I mean there are some that run $130 for a 300 ft roll or like the Wisbro Hepex from the same company that makes the Joist Trak runs $179 for a 300 ft roll. Is it worth going with the more expensice stuff?

Thanks for that site!