Add-on radiant zone mistake for $250,000 addition

Mark Woll_2

Owners are adding a large 1 story addition (maybe 50 x 25') and installed a single zone of radiant floor heat. Here's how the contractor piped it to the existing boilers/standard cast iron radiator system: Do you see any problems?

The radiant zone isn't heating well.

In the diagram below, the small square box is a Sparco mixing valve.

(My impression is that the installer failed to properly install a primary/secondary loop with the red pipes. He needed to pipe a loop in the "red" system end and two Tee's not more than 12" apart to connect to the "green" system. Ideally, the Red B&G would be relocated to pump away, also.)

KCA_2

Looks OK


The overall piping looks OK.. What is th esmall circle? A temp gauge?

Not heating? what do you mean? Not well enough? Not at all? How many loops of what size tubing and at what loop lenghts?

Start there and we'll see
:-) Ken

Mark Hunt

First


The boiler should be piped P/S, your drawing does not show that it is.

I'm assuming that there is a seperate T-stat for the rad zone?

I see what looks like 3 circulators, two of which are connected (circ on the rad zone and one on the return red circuit) If that is the case, then the B&G 100 is fighting with the radiant zone pump.

Is the radiant independantly controlled?

Mark H

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Mark Woll_2

The circles are all pumps...

There is a separate three dollar thermostat for the radiant zone controlling the Green radiant zone pump. The operating parameters of the red zone (the existing B&G 100) have not yet been determined, though it appears to run simultaneously with the green pump. The last circle ("black" pump) is a 2" B&G circulator which is not really in issue at this time as it circulates the rest of the house which heats nicely.

The radiant zone fails to heat the floor sufficiently.

Mark Woll_2

We do not know the tubing lengths yet...

The diameter of the lines and length are not in my notes yet, but I will get it in another visit.

There is some heating, but it appears to be inadequate.

I have not performed any flow analysis or calculations yet because I see such a glaring error in the p/s piping where the red meets the green.

Dale

Too long lengths

If it turns out the problem is really too long lengths you may need to use the hot rod trick of a 4 way valve timed feeding from different directions.

Mark Woll_2

pictures of the boiler room, what a mess

Here's the boiler room, but not the radiant panel pumping station which is located in a different room, and which I didn't get a picture.

Einsiedler_2

mix valve

the mix valve s/b on the supply side feeding infloor.. no??

to me it appears this mix valve is incorrectly placed.

EIN

Tim Doran

Problems/Questions

First off, the pipng has a bit to be desired as Mark Hunt pointed out. The two pumps are in series on the RFH. Primary secondary, a bypass, or elimination of the RFH pump nearest the boiler return are all options.
What is the design flow and delta T? How long are the loops and how many are there? how many btu/sqft are you trying to deliver? What is the RFH pump? What is the three way valve and what is it's Cv rating? What are all of the pipe sizes?


Tim D.

Mike T., Swampeast MO

From the Way You Describe, the B&G is Driving the Radiant

Such is not a good application for a circulator that likes high flow and low head. Radiant applications generally call for the opposite, with low flow at high head.

Ted_9

This calls for a radiant professional stat!


PATRIOT HEATING & COOLING, INC.

Ted_9

Here's a great question. Why wouldn't someone install a properly designed and installed system for a 250,000.00 addition????

PATRIOT HEATING & COOLING, INC.

lchmb

looks

It look's like alot of work need's to be done on that system. I agree with the other post's that you need a p/s layout. I would also say looking at the pic's that you need to do some repiping on the boiler but that's just because it look's like a confusing mess....

Mark Woll_2

Yes, how could they spend such money and not do the heat?

Yes, as it turns out the owner is a neighbor. I was brought in at the job's beginning for some general discussions, then never consulted again until it got cold out. My emphasis was to design a completely new system and rip out virtually everything in the photo above. This fell on deaf ears. The heating was not a concern in the slightest at the time. They were far more worried about countertop granite colors, kitchen cabinet hinges, and skylights.

I was told by the owner and the general contractor not to bother designing anything, to go on home, they'd take care of everything. They had their own radiant expert, an alleged 35 year veteran.

joel_21

thoughts

Piping is a problem but well everything here is. Why doesn't it have a weather responsive controll?? what's the floor covering? Is it staple up? If so does it have plates? How much insulation bellow? those are all huge factors. I agree piping isn't Rosy but make sure you cover all the base's and fix them all. If you repipe and it still doesn't work the owners will probably try and stick you with it at that point. So I've always found it safer to recomend and fix it all or walk away. If not you can inherit a nightmare. Don't ask me how I know.....

Ted_9

They had their own

> radiant expert, an alleged 35 year veteran.




Famous last words.

PATRIOT HEATING & COOLING, INC.

Mark Hunt

As I said


If that piping diagram is acurate, the B&G is fighting the rad pump when both are running.

Why would the water want to go through the mixing device when it could just shoot straight back to the boiler?

Look at your drawing and "see" the flow issues.

I have a little pump (007 no doubt) trying to pull against a B&G 100. The 100 has relatively 0 pressure drop compared to the 007 which has to pull through the mixing device AND the small radiant tubing. Which way would you go if you were water?

Mark H

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Jeff W_3

i concur

The piping is definately not perfect but would work. There are many more factors to consider. Installation method, staple up, slab, with or without plates?
B.t.u. per ft. requirement? water temp? Properly sized pump, loop lenghts.
The boiler piping is obviously a disaster but the way it's piped will work. I don't think the problem is anywhere near the boiler.

m dewolfe

lots of chilly nights

1250 sf and one loop of radiant? Can I sell you a salamander heater?

Mark Woll_2

Yes one zone, I recommended three way back when...

Here are some details:
Original house: Philadelphia formal colonial, all stone 3 floor, 8.5 foot ceilings, 1920 construction date, quite expensive, probably 3500 sf,
--original gravity water, typical radiators, converted sometime later to pumped circulation.
--boiler arrangement (now get this!) original unknown, now it has 2 parallel HydroPulse @100K btu units the supply sides of which are permanently piped (in series I guess) to the RETURN side of a huge ELECTRIC (Gentlman Janitor Brand) Boiler. This electric boiler, the owner tells me, runs only if there's a problem in the HydroPulses or if it's too cold.
--circulators, one large 2 inch B&G on the main line, pumping toward the expansion tank, naturally, with two recent 3/4 takeoffs to #100 B&G's, one for a room above the garage, and one which was for the old now torn-down addition, resurrected to be used with new radiant zone.
--control system, it has an antique HeatTimer (Hah!) control to reset the HydroPulses to outside temp, and a ton of other garbage. There's an aquastat in the picture, maybe it cycles the HydroPulses, maybe not I haven't sat down to figure it out yet.

The addition is typical wood framed, 2x6, extensively glazed vaulted ceiling den, kitchen, laundryroom and mudroom. Radiant tubes embedded in a gypsum pour (I suppose with wood nailers) to allow the finished hardwood flooring to be secured. No carpet. Wirsbo pex tubing I don't know what diameter.

Mark Woll_2

Tell me about it!

Mark Woll_2

More photos of the boilerroom for those masochists out there!

No. 5 has nice detail.

Weezbo

i can see the reluctance to move the electric boiler....

how ever, that entire space could look so much cleaner... as to your questions,really a simple by-bass in the station for the radiant would help the entire deal how much ? anyones guess. the lay out of the loops, thier lengths,thier size, the floor covering , insulation ,windows doors.......on and on all those things have a certain sway on the heating of the area...are there any temp gauges in the supply and or return from the loop? without jumping to convulsions has the new radiant system been Purged of air? is there a spirovent anywhere in the system ? are there zones off the other (field side) of the mixer? does it have enough room to connect an injection system at the station?,ifso,you could still use the recirc pumps in a different location however for my money it would be bye bye B&G Hello taco pump block:)

Mark Woll_2

I'll be out there tomorrow to see it again

> how ever, that entire space could look so much

> cleaner... as to your questions,really a simple

> by-bass in the station for the radiant would help

> the entire deal how much ? anyones guess. the lay

> out of the loops, thier lengths,thier size, the

> floor covering , insulation ,windows

> doors.......on and on all those things have a

> certain sway on the heating of the area...are

> there any temp gauges in the supply and or return

> from the loop? without jumping to convulsions has

> the new radiant system been Purged of air? is

> there a spirovent anywhere in the system ? are

> there zones off the other (field side) of the

> mixer? does it have enough room to connect an

> injection system at the station?,ifso,you could

> still use the recirc pumps in a different

> location however for my money it would be bye bye

> B&G Hello taco pump block:)



The floor coverings is hardwood, insulation is r16 new construction, loop lengths unknown, air in loops? who is to say

Mark Woll_2

A bypass to properly set up p/s is logical

I'll be going there tomorrow to follow up on odds and ends. No airscoops. stay tuned!

Mitch_4

If I were you

I would stick by my original quote. Rip er out and do it right. I cannot see anything but what you originally said, and that includes ripping put the new radiant...and make em pay.

They ignored you most likely for the cheapest price, and now they want it fixed right...so they call you, cuz you know these systems. But obviously that knowledge was not required or worth the price.

My stance would be " Can't fix..rip it out and redo ...LIKE I SAID AT THE START!"

1200sf addition and 1 loop????? HEllo?

You may be good (2 "o"s not 1)

or

"Get your "35 year vetran "EXPERT(?). Not my system, not my problem"

laugh and walk.

Bet the new counter top bill exceeds what they paid for the heatin system. I hate cheap people like that.

I have had friends get others cuz my materials cost more than quotes they received.. then they want me to fix..I say no. get your guy, that's why you paid him. For a working system..

Sorry for the rant. This cr*p really gets the draft going in my vent stack.

Mitch