I am struggling with Hot Surface Igniters that don't last long. My understanding is, with this paticular appliance, if the igniter isn't pulling 3.3-3.6A, then the gas valve won't open. Our present igniter, the third one, didn't light the broiler today and sure enough, I got 2.9A with an amp clamp.

My question…. Are there different quality options with these things? Put another way, should I avoid generic units made in <insert country with low labor costs> and buy from <these guys>?

Granted, heating a chunk of silicon carbide to red hot over and over probably isn't a great design but I'm stuck with it. Anyone wrestled with these? Thanks in advance, C.

Would serve an above garage appt, a laundry tub, and a lav. Sometimes the space will be used regularly (renter); other times it will see light use (plan to feed one main-house bath lav off of it).

After lengthy consideration, I've ruled out all styles of recirculating pumps, and CW fed tankless HW heaters would require 50A or more of service.

The volume of the 1" PEX that will feeding DHW to the space is about 2.1 Gal. Will also have low pressure at the garage.

I'm exploring the idea of a 6-8 gallon electric tank HW heater (3/4" fittings) at the site of the garage dist manifold, fed by the indirect. Anyone seen or tried this before?

That number has puzzled me for years. Water boils at 212 degrees under normal atmospheric conditions. So how can condensation be happening at flue gas temps closer to 300?

So I asked Google AI. And to my surprise, I learned something. This is a summary of what Google AI said:

"Water Dew Point vs. Acid Dew Point:

The water vapor dew point for heating oil flue gas is typically 115-125 F, while the small amount of sulfuric acid in the flue gas typically has a much higher dew point, typically from 248 to 300 F, which means corrosive liquid can form long before water vapor appears."

I had not heard that explanation before, and finally it all made sense. So it's the high acid dew point that we're trying to avoid.

The AI answer included a link to a useful paper about dew-point corrosion in boilers, which I'll include below.

https://www.nationalboard.org/PrintPage.aspx?ID=196&pageID=164

Thanks

Jeff perry

Here is where I need help:

1. My risers & return drops are approximately 9 feet. Will it suffice to use one venturi tee on the return side of each rooms circuit?
   1. Do I need a cast venturi tee? Some are rough castings everywhere except the pipe sweat surface. (I expected at least the reduced opening would also be machined for predictable performance). Perhaps I'm too particular!
   2. I'm tempted to use 3/4 x 3/4 x1/2 Tee w/ a NIBCO venturi insert. Anyone have experience opinions about this option? If I go this option I'll be scribing the standard tee to indicate the insert & it's direction.
   3. I have pipe chases where the supply and return for adjacent circuits are co-located. I put the return venturi tee 16 inches prior to the pipe chase and the next room's supply tee (3/4 x 3/4 x1/2, no venturi) 16 inches after the pipe chase. -Is this much separation necessary (advisable)? Alternatively, is it better to place the venturi at the pipe chase and the supply some distance downstream? What is the recommended separation distance?
2. I'm working up circuit distances in pipe equivalents…
   1. These distances will inform decisions about whether more than one venturi is required in a circuit, right?
   2. The circuit distances are from the boiler supply manifold to the boiler's return manifold, correct? (not just the 1/2" branch and the radiator length)

Would really appreciate some experienced guidance. Thanks in advance for weighing in!

Context:

I'm in the midst of adding the 2nd floor zone to the heating system in my childhood home here in New England. There were 3 bedrooms, a half bath and seven of us on that floor(and more down below). In the winter the interior of the double pane windows would ice up as there was either a Tilly kerosene heater, or a shoe box sized electric heater to supplement convection up the stairwell to "moderate" the temperature. -We all survived.

I've found my Dad's plans for a proper heating system (boiler size, radiator placement (cast iron Base-Ray), riser & down flow locations as well as piping (3/4" copper -main loop, 1/2" copper branches) etc.

I also found some of the difficulties he ran into which certainly contributed to the system never being completed. (He mounted some of the Base-Ray radiators, installed underfloor piping, dropped some risers to the basement, then stopped.)

His design called for a 12 ft. run of radiator in each of the bedrooms. Two of the rooms are 11' x 12'. Hence no room for valves or fittings to pipe those radiators.

Now 60 years later I'm finishing up. Fortunately he purchased all the radiators for the system. Unfortunately 16 ft. of uninstalled sections of radiator were left outdoors and had to be scrapped. Also unfortunately, but predictably, the Base-Ray castings have changed so old & new won't mate to each other. But, you can plumb old & new end units together (just not intermediate units).

To solve the space issue, I plan on placing a 24" panel on the adjacent exterior wall and using Burnham's 10.25" 90 degree compression piping to connect the remaining 10 ft.

It seems to work (in my head and on paper). But, I don't know what I don't know. A somewhat precarious position. If you can reassure me that I'm walking parallel to a cliff and not toward it, I'd be most grateful !!

Jack Spade

I have a hydronic heating system with a 100k BTU natural gas boiler (Utica model MGB100HID). This boiler is approximately 25 years old, and the silicone which seals the draft hood to the heat exchanger had begun to crack / peel. Before the start of this heating season I decided to replace the worn out silicone with high-temp red RTV (Red Devil P/N 08090I; rated to 600F)

I've run the boiler a total of ~5 hours since installing the high-temp RTV, and each time I run the system it emits a smell which smells like burning plastic. (Note - this is just a smell that fills my basement; there is no smoke). At first I thought this might be a normal "burn-in" period for the new RTV, however, after multiple hours of running the system with no signs of improvement i've grown worried that this smell is never going to go away…

I don't believe that i'm overheating the RTV in this application - I attached a thermocouple to the external side of the vent hood and am measuring a max of ~325F when the burner is firing. Additionally, the Utica installation manual appears to spec a silicone sealant (GE IS808) for this location which is only rated to 400F.

For now, i've been cracking my basement windows and using an outward facing fan in one of the windows to keep the smell from building up. This seems to prevent the smell from making its way upstairs.

I guess what I'm trying to figure out is whether new high-temp RTV is expected to smell like burning plastic when heated? And if so, how long should I expect this burn-in period to last?

Any input is appreciated.

Thank you!!

This fitting is on my heating system. Thoughts….leaking? I have boiler service scheduled for thursday.

Thank you, Flo.

I also like to add blow-downs to all my wye strainers. What's the best way to do this? Just thread a short nipple and add a valve with a plug? I really want to know what brand and style valve is suggested.

Lastly I noticed this setup appears to be missing a relief valve in the last picture? Unless there is a reason for that I could be unaware of?

Thanks for any input! I am just a custodian who has only figured out these terms and info from being in this building and reading up on how these systems work. I realize steam can be very efficient when maintained. From reading through old posts here it sounds like there is plenty of buildings like mine that have never done any preventative maintenance and only acknowledge things when they break.

Any kind of bent pipe or elbow fittings I can use to bridge this gap? OR take / cut off the shutoff valve and extend it up an inch or so? OR should I just look at getting a new (to me/used) radiator with a matching height (or shorter, to shim up) ?

We're looking to buy an old house in Brooklyn and it has this ancient thing in the basement - a Richardson 1282? We've been told it's a gas and hot water system.

Though it seems to work, our assumption is that it would be best to replace it before we move in because the cladding probably has asbestos.

Do readers agree? and is it really 80+ years old? That seems wild!

System Configuration:

 Heat Source: Navien combi boiler configured with primary/secondary piping.

 Circulators: Dual Grundfos UPS15-58FC wet-rotor pumps (multi-speed).

 Distribution: Uponor radiant manifolds with built-in flow meters.

 Controls: Tekmar 519 thermostats managing zone calls.

The Symptom:

The system exhibits a bizarre hydraulic "run-out-on-the-curve" behavior on the secondary loop. When the manifold balancing/ball valves are fully open, the Grundfos circulator appears to stall or lose its grip entirely—flow drops to near zero across the manifold flow meters, regardless of whether the pump is set to Speed 1, 2, or 3.

However, if I partially throttle a downstream ball valve to artificially introduce head pressure, the pump instantly catches, flow stabilizes on the meters, and the system circulates properly.

What's Been Tried:

My plumber has already swapped in three brand-new pumps trying to solve this, and the exact same behavior happens on all of them. Changing pump speeds (1, 2, 3) has zero effect on the stall behavior when the valves are wide open; the pump acts identical across all speeds.

Here is a photo of the mechanical board layout:

(Attach the photo here)

Has anyone run into a similar scenario where a Grundfos circulator on a low-resistance loop requires added downstream head resistance just to maintain its vector flow? Any insights on whether this points to an air-binding quirk, a primary-secondary hydraulic decoupling issue, or differential pressure across the circuit would be greatly appreciated.

SYSTEM

• Noritz NRCB199DV, manufactured Oct 2018. Space heating only - the DHW
  ports are capped, domestic hot water comes from a separate gas tank.
• Rating plate: heating capacity 120,000 Btu/h.
• Supply setpoint 160-165F.
• Four zones on an Argo panel - zone valves, one circulator, plus the
  boiler's own internal pump.
  1. Basement baseboard
  2. 1st floor baseboard
  3. Owner's suite baseboard
  4. 2nd floor apartment, forced hot air through a 12x15 water-to-air
     coil in an attic furnace
• Boiler is in the basement. The attic coil is above the 2nd floor -
  call it three levels of rise.
• Mix of old iron/galvanized and copper. Municipal water.
• No record of the heating side ever being flushed, cleaned or treated.
  No real maintenance for many years.

THE FAULT
Intermittent shutdowns on Error 54 (low heating water pressure) and
Error 57 (auto feeder open more than 600 seconds). Power cycling resets
the timer and it runs fine for a while, then does it again.

WHAT WAS FOUND AND DONE LAST YEAR
A plumber replaced the expansion tank and the boiler's internal
auto-feeder inlet valve. Two things from that job that I only recently
understood:

1. The old feeder valve's internal black rubber filter screen had
   completely collapsed, squeezed down and turned INSIDE OUT.
2. The invoice reads, word for word:
   "Replace expansion tank that's for domestic water with proper
   hydronic expansion tank #30. And proper pressure gauge. Pressure was
   low so turned up fill valve/prv to 15 psi. Boiler running at 20.
   That is correct to pressure."

So a DOMESTIC water expansion tank had been sitting on my hydronic loop,
along with a domestic 0-160 psi gauge (photo 4). Both were replaced with
an Amtrol #30 and a new gauge. Nothing on the invoice about setting the
tank pre-charge. The relief valve was not touched.

Less than a year later the E57 timeouts are back.

The expansion tank sits on the floor in the corner, several feet below
the boiler (photo 1, bottom centre). The new one went into the same
spot, just larger.

NO VISIBLE LEAK
Nothing wet, no puddles, no staining on the floor. The only thing I can
see is rust-brown streaking running down the side of the OLD tank in
photo 3.

PHOTOS

1. Near-boiler piping. Argo panel on the left, old expansion tank on the
   floor at bottom centre.
   2. Same wall with the boiler's front cover off - taken by the plumber
   during that visit.
   3. The OLD expansion tank, the domestic one. Note the rust staining
   running down the shell.
   4. The OLD pressure gauge. Everpure, 0-160 psi.
   5. Zone valve manifold, on the wall opposite the boiler.
   6. Rating plate.
   7. Other side of the room - separate gas DHW tank, Argo panel, the
   circulator, and the old expansion tank on the floor at right.
   1-Near-boiler piping. Argo panel on the left, old expansion tank on the%0A floor at bottom centre.jpg
   

QUESTIONS

1. What makes a feeder screen collapse and turn inside out? I assume
   flow went backwards through it. What drives that?
2. If a domestic tank (40-ish psi pre-charge) was on a loop running
   15-20 psi, am I right that the diaphragm never moved and I effectively
   had NO expansion capacity for years? And would that have had the
   relief valve lifting and reseating every cycle - dumping water, the
   feeder making it up, over and over? If so, is the relief valve seat
   likely wrecked by now and weeping on its own, even with a correct tank
   fitted? It was never replaced.
3. Is 15 psi cold fill enough with the attic coil three floors above the
   boiler? My arithmetic says that leaves the coil at roughly 2 psi,
   which sounds like air vents up there ingesting air rather than
   purging it.
4. The tank is on the floor several feet below the boiler, and there's
   both an internal boiler pump and a separate circulator (photo 7). How
   do I confirm the tank is on the right side of the pump? If it's
   wrong, could the pump be pulling the top of the system toward zero
   every time it runs?
5. Could years with no flushing in an iron system silt up the boiler's
   pressure sensor and give me a false E54 rather than an actual leak?
6. A contractor has proposed capping the internal auto-feeder entirely
   and fitting a standard external fill valve with backflow preventer on
   the loop, to get past the 600-second timeout. Reasonable, or is that
   just hiding a leak I haven't found?

Tell me what to photograph and measure Wednesday and I'll get it.

Thanks.

In January 2012, I noticed that I was adding a ton of makeup water. The block was cracked. I got a new one under warranty.

In December 2013, we switched to natural gas and got a new Weil-McLain boiler and an HTP indirect water heater. The contractor also fixed a lot of issues with the previous install (https://forum.heatinghelp.com/discussion/147386/whats-wrong-with-these-pictures).

In October 2025, the coil in the water heater sprung a leak and flooded the boiler and nearby piping (https://forum.heatinghelp.com/discussion/202257/dirty-hot-water-boiler-overfilled-related). Replaced under warranty.

Just a few days ago, the annual boiler maintenance revealed a cracked block again. Warranty expired three years ago.

What's going on? Is my town's water supply mixed with battery acid or something? What's the expected lifespan of a steam block?

Once the new boiler goes in, what should I do differently? Periodic testing and treatment of the boiler water? Whole-house water treatment?

My existing radiators have 343 sq. ft. of EDR. I consulted the old manuals directly, so I'm pretty confident in that number.

At one point, we considered adding radiators back to one or two rooms that previously had them. I think we'd probably have slightly more even heat distribution if we added them back, but it's been fine without them. (I have no idea when or why they were removed.) Referencing the indentations on the floor where I assume the feet used to be, I estimated an additional 80 sq ft of EDR in total for the missing radiators. The odds that we ever add them back is pretty low, but not zero.

We have a 60-gallon indirect water heater and two teenagers.

Most of the piping in the basement is wrapped with 1" insulation, but the elbows and other connections are not insulated. There are also some pipes in a crawlspace that are not insulated, partly because of access issues and partly because there are water lines in there that I think deserve a little heat.

I know I could insulate better. I did what's there myself, which is why the more complicated stuff isn't wrapped. I actually got a quote earlier this year to finish the job, but the cost seemed very high for the expected payoff. I might have the contractor insulate the new near boiler piping and tackle the rest of the gaps myself.

The Peerless 63-03 is rated for 308 net sq. ft. of steam , 63-04L for 383, and 63-x-04 for 388. US Boiler's STMX125 is 321, IN5PVNI is 363, and STMX150 is 388. Weil-McLain's EG-40 is 321 and EG-45 is 388. There are probably other options too. Of course, I'll have to work with what's available and what the contractor likes to work with.

I'm between sizes, and that's just taking into consideration my radiators. Factor in the indirect water heater that isn't going anywhere, the missing insulation that could be fixed, and the missing radiators that may or may not reappear, and I'm not sure what I should do about sizing.

Suggestions?

I have two, so I just have to wonder if it’s the actual thermostats but these existed before my new system and the variance just didn’t seem to exist before. I’ll be downstairs and it’ll show 71 but my probe shows 74-75.

I went with a 2 stage Rheem, and it seems to be working but it’s worse than my old system and not sure if it’s just because of the thermostats but they worked ok on my last system.

Should I invest in nest sensors to supplement? Or switch over to Ecobee? I am also concerned that they are wired differently, one has the red wire in Rh and the other has Rc.

Any suggestions?

I can open a series of openings to get the string through. But then how to repair these holes?

I skimmed some where between 25-30 gallons. At the end the water coming out was a shade of yellow. I filled two glasses, one with tap water the other with the water from the boiler. I am a first time skimmer. Would we call this sufficiently skimmed? See photo below.

Thank you.

I'm hoping to get some expert opinions a remodel situation. I'm doing a complete demo and rebuild of one of our bedrooms. It has Base ray cast iron baseboards along one of the walls (I'm in a Philadelphia row home - baseboards are along a brick party wall). While I'm remodeling the room, I have the cast iron baseboard pulled out. The Hydronic system is a simple series loop( 2 pipe direct return or parallel), so while this baseboard is out, I have the sytem drained and turned off. Thing is, weather is starting to get cold, and this remodel is probably going to take me another 2 months (+2 more months for wishful thinking). I need the baseboard to stay off cause I will need to frame, drywall, install flooring, etc, but I will probably need to refill and turn the system back on soon. I'm trying to plan out a modification so that I can get the system back on, with the baseboard off. 

Is this an appropriate use case for the monoflow tees to bypass the radiators? It's a 3/4" copper main. Was thinking of converting to 3/4" oxygen barrier Pex for any replaced/new sections, using expansion fittings. I tend to see 3/4" x 3/4" x 1/2" monoflow tees, so was planning on using that sizing. I understand that there's pressure drop to consider in this situation, and the pex inner diameter is slightly smaller than copper. Not sure if this conversion warrants a recalculation of the components, or if it "should be fine". As of now, the system works just fine. 

This is a 2nd floor bedroom, and it seems like the simplest way to get to the piping is to cut open the living room ceiling from below. Open to other ideas! Here's some crude drawings of the space, and what I'm thinking. Long term, I'd like to remodel other bedrooms, and likely want to install a similar bypass on those radiators as well.

I wonder if a standalone electric water would be a valid option? I know it would be less efficient, but if oil prices stay as they are now, I was thinking during the warm weather season I could just turn the furnace off? I asked about that a while back before this happened and heard due to the efficiency of the Buderus system that may not be the best option.

I realize the during cold weather the indirect system would be more efficient when the furnace is running. Maybe the best choice overall would be the indirect system. The furnace is 24 years old. I don’t have the knowledge about these systems and respect those that do and appreciate any ideas.

I just stumbled upon this website today while trying to learn more about my current heating system. I have a Hercules boiler- I believe it was converted from coal, to oil, and then gas. The house I live in was built sometime between 1890-1910, and I was wondering if anyone knows how old this model is?

I'd also like to know how efficient or inefficient they are. My brother and an HVAC guy who serviced it in the past both think I should keep it going until it fails. I figured it might be worth reaching out to see who else might have one, or who has worked on one, and gather more information about this Hercules in general and what their thoughts are on keeping it running versus modernizing??

I have steam heat with old-fashioned radiators.

Thank you

So much is wrong, it makes me cry.

Besides the pumps pushing into the bottom of the boiler, through undersized "return manifold/header" steel pipe. The fresh water supply snaking from right side ceiling, behind the boiler around the left side through a pressure reducing feed valve, snaking across the boiler top front to the right side back and shockingly down into the the return manifold. The boiler supply piping coming off the face of the boiler where the pressure gauge should be. The pressure gauge is in the pressure relief valve port (relief valve is installed into the upper back side of the boiler). The top right port should likely be THE supply, but has a float air vent. The existing supply piping is undersized, going left to two zones and to the upper right into the only air-scoop. 😱 Which is rotated & slanted down. The bladder tank is inverted & angled. The outlet of the air-scoop is 1/2" pipe into a flow check the changes back to 3/4" pipe for the basement zone. There is a zone return pipe 4 inches in front of the damper (service guy doing a vac & tune not happy). One of the flow checks is letting ghost flow upstairs; causes some short cycling of the burner and making that zone hot.

I just want to straighten out the supply piping and air scoop. This might be replaced with a gas fired boiler within 2 years. Reluctantly leaving the pumps to push into the bottom return. I think that the fresh water should NOT go into the return. I could leave the 1/2" pipe as a passive bypass from the boiler hot supply. Then re-route the fresh water into a tee for the air-scoop bottom port with the bladder tank. Which should be 18" horizontal pipe from the elbow off the vertical 18" high supply pipe, from the top right port. All three zones' supply piping should be from after the air-scoop.

What do you think of my plan? Did I miss anything (besides pumping away)?

w to add a air to water heat pump to my radiant floor heating system running on a propane boiler. Buffer tank that was sent is 2 port. Anyone has any advise in how to pipe it all up? Here is design I got do far.

My main circulating line is 3/4" copper, so I just branched off of it using 2 standard 3/4 x 3/4 x 1/2" tees (not monoflow) spacing them roughly the same width of the radiators and then sending the 1/2" lines out of the wall 2" apart to go into the Isolator/By-pass H-valve on the bottom of the rad.

They seemed to work fine and heat up nicely after I fiddled with the flow screw in the bypass valve (If I remember right I think i may have nearly had to shut it off completely, like barely a 1/2 turn open) …

So did I just get lucky and created enough pressure drop by spacing the standard tees or do I still need to use monoflows on the tee returning back into the main 3/4" line? (I thought the bypass took the place of the monoflow??!!) I see the diagrams for a standard single run line system but I'd like to replace several of the finned baseboards. and it seems to make perfect sense to branch off of the main 3/4" to run through each rad and let the bulk of the hot water keep flowing on the the other rads down the line…

The 3 I installed work soooooo much better than the old finned baseboard that I want to replace all of them (well some of them and I'm going to delete others.) About 14 total radiators on 2 floors in 3 different zones. Anyone that can help me I'd greatly appreciate it. I've been scouring the internet for more info on my particular system with no luck. I can provide any and all information you may need to help me! - thanks, brad

Other misc info: Boiler is in the basement and has 3 circulation pumps pulling the 3 zones into the boiler (cold side) It runs at 15 psi max and about 160ºF.

Pex Universe Radaitor:
https://pexuniverse.com/20-x-24-hydronic-panel-radiator-model-22

Isolator/Diverter H-Valve:
https://pexuniverse.com/beacon-morris-radiator-isolation-valve-angle

Any idea where i could find burners for this boiler. Was in a foreclosure and the previous owner took a few of them.

What are the drawbacks of placing the Large Pipes somewhere other than directly onto the buffer tank ports ?

I would prefer to mount my Large Pipes vertically and closer to the wall. This would reduce stress on the buffer tank ports as well as leave the piping a bit more open to future changes of buffer tank. Planning on using 1.5" tees for the Large Pipe.

I need a refresher.

All things being dandy, boiler makes steam, steam fills the piping system (hopefully without too much loss due to cold pipes). As the steam reaches each radiator through the top valve at one end and fills the radiator, the air escapes through the bottom valve and heads down the dry returns back to the boiler and continues its escape through the large return vents back at the boiler.

There is no visible devise at any radiator to prevent the steam from following the air through all the dry return pipes and out the return main vents back down to the boiler.

This is a 1920's system with virtually no changes other than the boiler and the deletion of radiators. One that was on the ceiling in one of the rooms in the basement and one on the second floor landing.

My question is how did the steam stay in the radiators back when in 1925?

I've been reading The Wall and learning from Dan Holohan's work as I prepare to replace the steam boiler in my three-story home near Berwyn, PA (Main Line area, west of Philadelphia). House is from the early 1900s. I'm hoping this community can point me toward a contractor who truly understands steam.

My System:
Two-pipe steam
Original cast iron radiators throughout
Calculated EDR approximately 860 sq ft

What I Need:
Boiler installation — Looking to install a Peerless 64-07

System troubleshooting — I have some banging in the pipework that I'd like diagnosed and corrected. Likely pipe pitch issues. I want someone who can evaluate the system properly and fix the root cause.

What I'm Looking For in a Contractor:
I'm not chasing the cheapest price — I'm looking for the right person.

Deep steam expertise — Someone who really knows steam and can troubleshoot an old system, not just swap equipment

Experience with old homes — Early 1900s construction has its quirks

A long-term service relationship — I want the contractor who installs it to maintain it for years to come

Fair pricing — I'm prepared to pay for expertise

Does anyone have a recommendation for a steam contractor serving the Berwyn / western Philadelphia suburbs area?

I've done my homework and I'm ready to be a good customer to the right contractor. Just need help finalizing a selection.
Thank you,
Matt
Berwyn, PA

Issue - Preventing short cycling, even though there are programs available on this boiler such as ramp delay, after reading many similar scenarios the general consensus from all the great contributors on this forum is the use of a buffer tank, just rehabbed my boiler room and now have space for one.

1,100 sq' ranch over a finished walkout, 4 different types of heat emitters, fan coil, heats entire main floor, fin tube base board, (heats half of basement, family room, laundry room and a mud room entrance, a 30"x30" Runtal panel (used as a point of use towel warmer) and radiant under 3/4" engineered hardwood over Warmboard, this is in the most recently finished second half of the basement, a small gym 12'x'22'. The radiant, 250' of Pex-Al-Pex has the lowest estimated figure of 7.5k btu/hr. This boiler has a 10-1 turndown (15.5K), sizing with a run time of 20 minutes comes up with a tank size of 16 gals, 10 minute run time yeilds 8 gallons. SupplyHouse offers two Zilmet Buffer tanks, one at 14 gals and another at 7 gals.

Questions:

1 - With the goal of eliminating short cycling, which tank (7 or 14 gals) do you think would be a better fit with relation to the varied emitter array? I'll be utilizing all three available loop temperature inputs highest at 155f and lowest at 110f

2 - 2 or 4 pipe configurations? Idronics #17 gives a great overview of the two scenarios especially with respect to liquid flow rate and path through the tank. Would the two pipe config be a better fit with the three different types of heat emitters? I don't think a delay in heated supply is a concern in such a small dwelling. The fan coil gets the most use during the heating season, fan coil target temp will be at 155f, I'm thinking the 4 pipe might give a lower return temp?

Some points: 1. Domestic hot water will be from a Lochinvar Squire SIT-040 pumped direct, not through buffer. 2. 3 variable speed circs will be used on the system loops (radiant and towel warmer will share a circ utilizing two separate zone valves. 3. Total estimated capacity of all zones and equipment including boiler and indirect is approximately 17.2 gals, the buffers at 7 and 14 would bring it to 22.72 and 29.72 respectively.

Install will follow the Lochinvar manual; the manual doesn't address buffers directly but does list closely spaced tees or a low loss header, the manual depicts placement of the system return temp sensor just before the low loss header, I'm assuming this sensor obviously would now be installed in the center thermowell of the buffer tank, and the boiler firing rate and primary pump speed will react to the rising and falling thermocline?

The boiler includes a Grundfos UPMS primary loop pump, this will be wired to and controlled by the boilers 0-10v output.

Sorry in advance if a little long winded.😒

thanks for any tips

Coincidentally and unrelated, the last couple posts I’ve submitted, the first one did not stick so I repeat the process and the second time it sticks

Am I impatient and it's will eventually open ? I had it running for probably 20 minutes ..

The instruction manual doesn't exactly detail what's the boiler in the picture..

Or more probably I did it wrong. Going to take a gas if it's something to do with the circulator location.. any help would be awesome thank you guys

hanks in advance guys

Here are a few pics

I have already had to fire up my boiler because temps have already been dipping into the low 40s in my area of Michigan and I’m not one of those people that fight turning my heating on lol. I like comfort and hate a chilly house.

In total, I have 11 CI radiators and 1 fin tube baseboard (2200 sq ft two-story colonial, built 1909). My system is 100% gravity, connected to my 1937 Ideal Boiler No. 7, I even have a Honeywell Heat generator connected to my system and attic expansion tank. (You can look through my old posts to see more on my well preserved system).

One thing that has always made me curious is why my small front vestibule radiator has two valves on it? This radiator, along with my dining room radiator, both branch off of the same supply and return lines in the basement.

Another weird one for everyone, four of my CI rads on the first floor have no valves at all. They are just always “on” piped into the system. Have any of you seen a radiator system setup like that with no valves on some of the radiators? And no, there are no valves in the basement to these radiators. Just your standard supply and returns lines to and from the boiler .

I am having zero issues with my system and everything works beautifully. This is merely just my curiosity and wanting to ask pros who have worked on 1000s of residential systems over the years.

Thank you!

Dining room rad, no valve.

One of my under the window Living room rads, no valve.

Kitchen Rad, no valve.

The Green Beast running the operation.

We recently completed a high-end renovation in Madison, Wisconsin, that included a radiant floor heating system powered by an IBC boiler. We’re experiencing a persistent problem: the alcove area consistently remains 10°F colder than the adjacent kitchen during the winter, despite both spaces being part of the same zone and having identical tile flooring.

However, the two areas differ in how the radiant heat is delivered:

• The alcove utilizes piping embedded directly into the concrete.
• The kitchen uses an aluminum heat transfer layer above the slab.

The builder claims that this temperature variation is “within acceptable range” and not a defect, citing the absence of an explicit performance standard in our contract.

We’re seeking input from HVAC professionals, radiant design experts, and others with experience:

Is a 10°F ambient temperature difference in a radiant slab system between adjacent spaces common or acceptable?

Some additional details:

• We engaged an independent HVAC firm that suspects a design flaw, but they’re reluctant to confirm without access to the system drawings, which the original installer refuses to release.
• Floor sensors are present, but their exact locations are unknown due to the limited documentation available.
• On our first night in the house (in December), the interior was uncomfortably cold and required backup heating. The next day, the installer switched the Aube TH114-AF-024T thermostats to “floor-sensing only” mode, disabling ambient sensing. This did not resolve the problem, and they have not returned since.
• To keep the kitchen comfortable during winter, we’ve had to set the floor thermostat to around 78°F. Despite this, the adjacent alcove remains 8–10°F cooler daily.

We are trying to determine whether this persistent differential reflects a design flaw, particularly given that the alcove and kitchen are thermally distinct and yet share the same zone and thermostat.

Have others encountered this issue in slab-based radiant systems?

Once defrosted the suction pressure never goes above 100 psi, and with 410a that is low enough for it to freeze. The txv was replaced, and the results were the same. The issue appears to be air flow, as the super heat and subcooling at the outdoor unit are good.

The air filter is clean and there are no obstructions in the duct work. I increased the airflow setting in the lennox wall thermostat/ controller to 1400 cfm from 1050, in an attempt to move more air. The LCD readout on the furnace says that it is moving 1400 cfm of air, but listening to the noise level of the furnace it sounds like the blower is moving at half speed. I put an ecm motor tester on the motor and with the tester the ESP reading was the same. .44

I have yet to find any documentation from Lennox where with an actual live esp reading can be compared to a chart, so the readout can be confirmed that is the actual amount of air the furnace is moving. Could it be possible that the fan motor is not turning fast enough even though the board appears to be sending the proper signal for the motor to ramp up to it's highest speed? Like I previously mentioned the external static is the same where the motor is hooked to the furnace's circuit board, or an ECM tester. Thanks to all

However, Colorado passed a low NOx law for gas heating units and I am wondering if there are any boilers out there that meet this requirement. I was looking at the US Boiler SteamMax, but this doesn't have a low NOx burner. Is it possible to retrofit a low NOx burner?

I would really like to keep my steam system. It is quiet and reliable. I don't want to spend $50K to put in a short lived (10-15 yrs), high maintenance, condensing HW boiler system.

Client also wants to have an option of the boiler modeled with a circular flue in addition to the standard square breaching - was this ever an option?

Here's the issue: I purchased a 50 gal. State HPWH, with a generous point of purchase rebate from Efficiency Maine and intended to use that exclusively for DHW. Low and behold, when reviewing the install instructions I discovered that the heat pump mode will not operate if water temperature in the tank is below 59 F. I knew about the HP cut out if the ambient air temperature is below 45 F (not a problem, it's in the basement next to the boiler) but I was unaware of the 59 F cut out for the tank water! In either case, if the temp is lower than the low default, the unit switches to the electric heating mode, which is not a step up in efficiency. We have a drilled well and the water temperature fluctuates from a high of ~52 in summer to a low around 45 F in winter, 7 - 14 degrees below the cut out year round. This is a problem since I purchase the HP to reduce our oil consumption (particular in the summer) and as part of an effort to improve energy efficiency. Though I am uncertain of how long the unit will have to operate only using the electric elements to raise the temp enough for the HP to kick in, time and experience will tell, I've decided to attempt an install that will allow use of either the boiler coil or the HP. The design I am proposing will allow me to isolate, drain and vent the boiler coil when using the HP and vise versa, if it turns out to be necessary to continue using the coil during the coldest months. I would appreciate any comments you might have on the functionality and safety of the proposed design and I will do my best to answer any questions.

I have attached three photos that hopefully describe the design in sufficient enough detail for reviewers to understand how the installation will work. I'll let them do the rest of the talking.

Thanks for any help,

Rusty

I'm learning a ton about the radiant heating system in my home through this site, and tackling my first project that requires me to touch the system. I'm currently remodeling a bedroom, and need to pull out the base-ray cast iron baseboard radiators so I can redo the walls, floors, etc. I was able to drain all of the water from the boiler drain valve. Now I'm trying to remove the unions at the baseboard inlet/outlet. The piping is very close to the wall (unsion is about 1/2" away from the wall). My pipe wrench has no space to turn at all. I was about to run out to the store to see what my options are, but I figured I'd ask here. Is there a special wrench that you all use in these situations? Or maybe another approach that I'm not aware of to remove this baseboard? Images below for context. Please feel free to correct my language if I'm using the wrong terms. Thank you for an awesome, very helpful site 🙏