WISE EYES NEEDED -- PUZZLER: What's Wrong With This Picture ? HYDRONIC Baseboard

REMIXME

Hello ! New to forum, but reading lots! Just a homeowner, but not physically able to do my own piping, so rely on the kindness of strangers for heat. I like to understand systems, so I've been reading and learning lots from you..some wonderful amazing kind souls here, bless you, and very much appreciate the tone and respectful approach the forum takes. This forum is the perfect blend of theory and practice, which makes it uniquely fabulous and helpful!

Before I sell my car to pay for a whole new system, maybe there is a basic re-pipe correction to be made ?

I thank you kindly in advance for all ideas and thoughts.

~~ homeowner, DEL NEWBIE (Mini-Therm near N. PA)

Here's some tech details, but assume some newbie errors, of course:

Issues: Laars Teledyne boiler WHINE, and LOW HEAT @ Baseboard ~115 even with 180 degree supply and pressure drops over 2 weeks so makeup water added often, possible LOW FLOW, possible SHORT CYCLING and likely not using NG efficiently. Train (KETTLING?) noise if bypass valve is not 100% open, (I have read the good Whining Laars threads),

System Details:

2-story House Square footage 2000 (8 ft ceilings with one great room 22 ft ceiling lots of windows), House 1970s insulated but leaky, poor foundation joist insulation, Altitude 1300
Heat Loss calculator said for whole house (Slant Fin) 80,000 btu
Heat Load: hmmm, one calculator said 70,000k but, only 27,000 btu if all baseboards are calling, (Original installer did not install ANY check valves or backflow preventers.)
System has no flow meters, no balancing valves, just the psi meter on the boiler itself.
Boiler manifolds are copper 1 inch with reducers to 1/2" outputs to PEX-PAP 1/2" (Kitec XPA)
Spirotube Fin Baseboard with all 1/2" pex inside baseboards
SpiroVent , Expansion Tank, Pressure Reducing Valve, thermocoupler, pump (each replaced once), Laars JVS-75 Mini-Therm NG Boiler (Net IBR 55,000btu)
Indirect Hot Water tank: Vaughn (replaced after 3 years due to leaking--we think installer dropped it)
Question: which circulating pump is best for this system (am looking at the Grundfos 15-58), as I suspect issue, & is 1 pump enough?
(Was ready to add circulators to every zone until I watch Siggy's video from the conference about one circulator systems)

My brain exploded when I tried to figure out head pressure.

STEVEusaPA

That’s a disaster. Does it actually work?
That one circulator isn’t going to do it.
If you’re adding water you have a leak-either in the piping and/or the boiler.
Without at least balancing valves, you’ll never get proper flow for one circulator.
The indirect may need its own circulator and hopefully it’s not piped in 1/2” pex.
Your heat loss seems way off.

REMIXME

Ummmm, kinda works.... to about 20 degrees outside, and we have a woodstove so always rely on it. Have found tiny drips on connectors and repaired, but I see two tiny drips on two others. Recent local HVAC guy did not see any leak inside the boiler. The indirect hot water heater IS indeed 1/2" pex, but the hot out into house is copper and the relief is copper. I do get hot water pretty okay from indirect. I will re-look at my heat loss numbers. Disaster, eh ? That's a place to start....is your gut reaction to rip it all out and start over, over tweek and upgrade a few things ?

Steamhead

I had to look up Spirotube baseboard- never seen it before. It's also known as Speedheat. Here's the rating chart:

https://www.spirotherm.com/sites/default/files/Speedheat-4A_0.pdf

Does yours have 3/4" or 1/2" elements?

REMIXME

Fortunately, the elements are 3/4". Unfortunately, everything attached to the ends of the tubes are reducers to 1/2" pex and often have harsh 90 degree connectors to do so.

Steamhead

How do the elements' capacities match the rooms' heat losses?

REMIXME

The Speedheat elements chart shows 752 btu per element at 180 degrees or 587 at 160 degrees but at 120 is only 288 and down from there. I am re-doing my heat loss calcs but I believe all of the baseboard is adequate except for the large vaulted ceiling room where the woodstove is and I am thinking about that issue too. The rest seem appropriate amounts of quality baseboard elements.

Rich_49

Is the shared return 1/2" also ? Why did you replace a 007 with a 0010 ? Very different performance . Did the system always have an air issue or did it appear after work was done or after the circ replacement ?

REMIXME

Yes, the shared return is 1/2" also. The 007 was replaced with the 0010 at a HVAC service visit when they were asked to do a full system troubleshooting to determine why the system was whining loudly, and failing to heat the house, and the tech went to a possible pump problem, after looking for a flow restriction of some sort, or a component failure. He never suggested any kind of re-piping.

Why they put the 0010 in is unclear. The system has had air in it a couple of times, and was purged. It only "gurgled" in the baseboard one time, and was purged, the connector leak fixed, and gurgle has not returned. The spirovent air scoop seems to be working right. Was checked at service call.

EBEBRATT-Ed

@Steamhead

I have used the Spirotube to replace old convectors etc. I don't know if they make enclosures for it If I remember right it will fit in a Sterling Senior enclosure. Has pretty high output and if fairly rugged stuff. I think I used 1" element on a problem job. Worked great

SuperTech

Looking at that boiler is painful. I hope that wasn't a professional installation.  It looks like they didn't care. Those zone valves....🤢. 

At the minimum I would get rid of the PEX to the indirect tank and pipe it with 1" copper and give the indirect its own circulator instead of the zone valve.  

Robert O'Brien

Revisit the heat loss. No way is a 2000 sq/ft home 80,000 BTU/Hr

REMIXME

HEAT LOSS (tried a couple calculators) about 60,000 btu

Thanks everyone for the responses and input. I am so glad to hear that the baseboard Speedheat fins can stay in the system and should work, if we can get it piped right.

Here's another drawing of the system.


WHAT TO CHANGE ?? Here are some of my guesses:

1. WILL definitely change hot water pipes from pex to copper !!
2. Will definitely hunt down leaks.
3. Will definitely add a few more baseboard.
4. WILL definitely ADD CIRCULATORS (but please advise where to locate them in the system diagram and how many, guesstimate....would you feel okay with just one more located at the boiler return, or does this mess need a circ on every zone?) I am thinking of replacing the Taco 0010 with the Grunfos 15-58 and adding another at the output of the return manifold just before it enters the boiler.

5. Add balancing valves (.... are they needed at EACH feed near the output from the manifold?) Can you recommend a reliable balancing valve with flow meter ?

6. WILL definitely do any other RE-PIPE .... but WHAT ? For example:

A) Guess the two zones that T into a single return should be apart and given each their own return on the manifold, and there should be no T's at the manifold

Should the manifold should be replaced with a new manifold with 3/4" outputs on the manifold ?

C) I am guessing that the Kickspace heater should be removed from the start of the MAIN run, and better located at the end of the return on a loop.

D) Should the 1/2" Pex be ripped out and replaced by 3/4" Pex ?

E) Bigger BTU Boiler ? My calculations point to a 99,000K-103,000K NG Boiler such as Weil-McLain or Slant/Fin but seems pointless until piping worked out

F) After installing circulators, guessing it probably will allow the Bypass Valve to be closed to about 25% (MAYBE ???) or install an automatically differential bypass valve ??

Apologies for too many questions and any that sound wrongly thought through. The original installers were indeed a company in business a long time, and the two companies that tried to help were also real longtime folks, but mostly oriented toward emergency "no heat" calls instead of system design, so I am trying to work with what I've got and improve it as is needed, but before I call the 4th company in to work their magic, I really need to understand what you guys, the true design minds think about best approach.

Again, thanks so much for any ideas and comments.

hot_rod

I think you need a complete do-over. If water has been continuously added the boiler is more than likely scaled, which may be the cause of the whine.

It will be tough for that boiler to deals with micro zoning like that and it will short cycle.

If you do stay with that boiler, I would add some buffer which will also give you hydraulic separation, allowing the boiler to have its own circulator.

Get a better load calc, see how the emitters match the room by room load.

You might spend $$ on upgrading the structure insulation and infiltration and relook at the load calc. A blower door test is a good suggestion for a leaky home. It will identify those leaks for you to seal. Infiltration can be a huge and $$ energy thief.

www.dsireusa.org shows some programs that might be available to help $$ with building and system upgrades, or possibly an energy audit, maybe paying for the blower door test at least.

REMIXME

Good Advice, for sure. I suspected as much. Thanks.

Can you explain more specifically what you meant by "If you do stay with that boiler, I would add some buffer which will also give you hydraulic separation, allowing the boiler to have its own circulator."

Also, any suggestions for good hydronic engineer to help near northern PA/NY border. Last guy was from Central NY. My search came up only with "knucklehead."

REMIXME

I had thought that the closely spaced T's were "hydraulic separation"...not sure what you meant by "buffer"

REMIXME

Am reading this https://heatinghelp.com/blog/get-out-and-learn/
and looking more into the hydraulic separators. Thanks...

woobagooba

$65 well spent.

https://www.amazon.com/Modern-Hydronic-Heating-Residential-Commercial-ebook-dp-B00B7M4Q8W/dp/B00B7M4Q8W/ref=mt_other?_encoding=UTF8&me=&qid=

REMIXME

Ordered, on its' way. Thanks for the nudge.😏

mattmia2

This is good as well:
https://www.caleffi.com/usa/en-us/technical-magazine

The issue with the water heater hx feed is not that it is pex, but that you can't get enough flow through 1/2" to get the full recovery rate of the tank/boiler combo. Probably should be 1". might be able to use 3/4" if you do the math carefully.

Brewbeer

The coffee with caleffi series was also good. You could choose topics.

REMIXME

Excellent help !! So much to learn now that I know 'just enuff 2B dangerous'

Followup question re piping from Hot Water tank to the manifold: If the 1/2" pex is replaced with larger pipe (let's say 1" copper), is that actually going to make a real FLOW difference in the boiler to help with my LOW FLOW problem since the hot water tank's pipes are reduced down to 1/2" right onto the manifold ? Seems to me that it would just be throttled anyway at that point so effect of increased FLOW "not so much".

REMIXME

Picture of the throttle point from Hot Water Tank

mattmia2

Oh, so your manifolds are 1" but it is a manufactured manifold with 1/2" take offs. You could tee in before the manifold with another separate pump before both manifolds and connect the DHW that way. You would need a flow check to prevent ghost flow when the other is not calling. Probably would want to set the DHW up as priority in the zone controller. Could also keep the zone valves and zone controller and control the circulators off of the end switches in the zone valves. It actually doesn't look as bad as I initially thought. Your issues probably are microzoning and not the right size circulator along with balance issues.

Did it ever work well? Are the zone valves each on separate thermostats?

REMIXME

Great ideas! I dont have a zone controller . No, it has never worked "well" but okay down to 20 degrees outdoors until recently when low flow to the boiler with the whining got worse. Yes, each zone valve has own thermostadt.
I had thought to add 2nd circ to the end of the returns pipe just after the manifold pumping towards the boiler. Had not realized DHW needed its own but had also thought to move its pex to the first position on feed manifold.

REMIXME

re Micro Zoning, will have to read up on that problem as I dont really understand what to change in that regard. The zones were together larger but split apart when system was not heating well.

REMIXME

Also, on the system drawing it seems the arrow direction is drawn wrong, that blue line whuch is DHW so arrow shoul be opposite flow going FROM dhw TO return manifold.