Poorly-Performing Radiant Heat w/Hydrotherm HC-145

Inquisitor

Greetings to ALL! As this is my first post, I was uncertain of both which Title I should apply AND how much data I should provide herewith. Thus, I'll attempt to be concise and support my statements w/photos, when possible. Here we go . . .
We live in a 3-story single-family home. We employ forced hot water via radiant baseboard heating to heat the ENTIRE home. Our gas-fired Boiler is a Hydrotherm HC-145. I have attached a photo of the manufacturers I.D. plate. The approx. max head distance from fill valve above boiler to the highest radiator (2nd floor, w/NO heating installed on 3rd floor) is 14'. The primary issue we're having is that the heat, although the boiler IS heating the tank and the circulator is functioning properly, will not bring temp up to thermostatic settings. Now, I'm a DIYer, as it relates to EVERYTHING. For this reason, I will need to make mention of several variables.
First, approx. 2 yrs ago, circulator failed and was replaced by lic. plumber. While here(and in addition to burning my fingers w/his torch, while I was holding piping), he also replaced a T-valve (see photo). However, in doing so, bc he didn't have a replacement valve, he removed the old Exp. Tank isolator valve and straight-piped from the Tee to the Exp. Tank (see photo[s]).
I have done a physical insp. of the exp. tank. The top 1/4 feels warm, while the lower 3/4 feels cool. Content volume assessment was supported by the "tap test." My conclusion was/is that the exp. tank is functioning properly. I should note here that I DO possess AND EMPLOY humility. I'm willing to concede any incorrect assessments when given professional instruction and guidance! O.k., next is the filling of tye boiler.
I have read ALOT of material about head pressures relative to distance. AND, I'm a former licensed Grade 3 waste water treatment operator. Thus, I'm educated and versed in hydronics and hydraulics. I understand that my boiler pressure should NOT exceed 25psi. HOWEVER, when I allow the autofill valve/system to fill the boiler, the fill shut-off doesn't close the H2O supply until the guage reads 28psi. When the boiler fires and cycles fully, the PSI INCREASES TO 40psi, WHILE THE BOILER TEMP READS 190 DEG F.. At this point, of course, I'm VERY concerned. I have tried several times, though, bring the psi bk down to more standardized thresholds.
This morning, I reopened the fill valve and allowed the boiler to fill to the auto shut-off lvl. I verfified cessation of inflow by listening to fill line AND feeling it, w/circulator turned OFF. Once I verified (AGAIN) that the auto shut-off is functioning properly, I went up to the highest radiator in the system and bled air out until I got a sustained H2O stream of VERY hot H2O. I verified "full raidiator" status by feeling ALL baffles. ALL of them were so hot to the touch that one cannot hold one's hand on them. Thus, as described above, I have filled the boiler to auto shut-off capacity, allowed it to cycle fully, and bled the system FULLY from the topmost radiator in the system. Indeed, ALL baseboards are hot, as is the topmost radiator. Despite all of this, a problem seems to persist.
The boiler seems to be cycling on and off more frequently than usual. HOWEVER, we're NOT getting the heat that SHOULD be yielded by the boiler. In fact, the thermostat shows ambient temp at 59 deg F, while the programmed temp settings are between 66 and 68 deg F, depending on TOD. I then thought the thermo might be off.
As it is a cheap effort, I changed batteries in thermo TWICE. However, I see no change in either ambient temp or cycling of boiler. Thus, I don't know if it's the thermo either.
The situational summary is this:
The system is full of H2O. ALL O2 bas been purged from highest point. ALL baseboards and radiator are hot. However, rapid cycling of boiler, but it doesn't seem to be yielding the heat that is has, historically. As indicated by Aquastat, immediately after boiler cycles, it is reading 40psi, at a temp of 190 deg F. I have examined expansion tank, as noted above, and it appears to be functioning properly. Basically, I KNOW the readings i've provided ALL exceed ALL recommendations I've read AND discussed w/plumber. Could it simply be a bad thermostat? Again, it DOES call for heat, BUT, boiler is cycling more quickly and NOT yielding historic BTU output. Could it simply be that the record sustained low temps outside are simply overcoming the performance capacith of the boiler/system??? Essentially, I'm seeking any/all professional input/recommendations so that, FIRST AND FOREMOST, I DON'T BLOW UP OUR BOILER! I have included photos of the above referenced parts and units, for everyone's recerences. I hope they help!
If you've made it this far, thank you so very much for your time, consideration of the issues stated herein, and your patience!

neilc

let's see a picture of the circulator and where it is in relation to the boiler,
one distant big picture\ showing it all.

Zman

It sounds like you have several different problems with your system. The first is the high pressure. There is no reason for the system to run higher than 15psi. Do you trust the gauge? Your expansion tank would need to be larger to run at higher pressure. What is the rating on your relief valve? Is it is the standard 30psi residential type? If so why is it not opening? Again, do you trust your gauge? If not buy a hose threaded gauge and verify.
I don't think any of the above is causing your problem.

System pressure has nothing to do with circulator head design in a closed system , think Ferris wheel.

If the boiler is maintaining a high temp and the radiators are not heating, it sounds like a circulation issue. Just bleeding until you get hot water does not mean you are not airlocked, air can be trapped on the other side. Feel the supply and return pipes to the radiators. Is there a temp difference? This is a sign of flow.

Taking pictures from farther back would help us understand your system better.

Gordy

First off the feeder is not set properly, or needs cleaned replaced. It should shut off at the max system fill for yours 12-15 psi.

Second the pressure relief valve on the boiler should be 30 psi. If the system hit 40, and the pressure relief valve did not open it needs replaced.

Third if the system pressure climbed that much either the expansion tank has failed, is improperly charged, or is not the right size. Could be a combination of all three.

Gordy

Are you sure the circulator is working sounds like no flow which is why boiler cycles.

Inquisitor

Hiya, Neil. Thank you for your interest, consideration, and response! Please find requested images of circulator attached. Also, I don't know that it's relevant, but the circulator is so hot to the touch that one cannot hold hand on it!

neilc

one more picture showing from the circulator all the way up to the ceiling,
we want to see all the pipes and how they're arranged

Inquisitor

Wow! Thank you ALL for your willingness to help! I will reply as quickly as possible, relative to my daily schedules!
O.k., ZMAN, first to respond to you:
1. "There is no reason for the system to run higher than 15psi. Do you trust the gauge? Your expansion tank would need to be larger to run at higher pressure. What is the rating on your relief valve? Is it is the standard 30psi residential type? If so why is it not opening? Again, do you trust your gauge? If not buy a hose threaded gauge and verify."
I have observed the PRV more closely, and have photographed it. Please reference attached pic(s). Indeed, the PRV has fresh H2O standing inside the female threaded(discharge) port. Respective of ths psi rating, it appears that it is a 30psi PRV. Again, please reference close-up pics. Also, no, I actually DO NOT have a secondary standard media to verify that aquastat readings are accurate. Consequently, I CANNOT verify accuracy, at this time.

2. "System pressure has nothing to do with circulator head design in a closed system , think Ferris wheel."
Yes, I am aware of their dissociation. Again, I was a Grade 3 WWT, in an "older life."

3. "If the boiler is maintaining a high temp and the radiators are not heating, it sounds like a circulation issue. Just bleeding until you get hot water does not mean you are not airlocked, air can be trapped on the other side. Feel the supply and return pipes to the radiators. Is there a temp difference? This is a sign of flow.
BOTH the feed AND return pipes are ALL hot, on ALL baseboards, as well as the radiator. If I had a cavitation issue on the return side, wouldn't the return be cool, or cooler, to the touch?

Again, thank you, ZMAN, for your interest, consideration, and response! Per your request for additional images, please reference the attached photos herewith!

Inquisitor

GORDY, this post is in response to you.

1. After I allowed the system to fill fully this morning, I manually rotated it to close it. It was a new valve, installed two yrs ago, when circulator was replaced(as cited in my initial post).
2. "Second the pressure relief valve on the boiler should be 30 psi. If the system hit 40, and the pressure relief valve did not open it needs replaced."
As noted in my original post, the PRV DID open ONCE, back when we lost power, and there was no cool H2O return to the gas system, which continued to heat the tank. Thus, I believe the PRV is good. Furthermore, as indicated in my post to ZMAN, the PRV DOES have a little standing water in it.
☆☆☆QUESTION: Should I shut down boiler, wait a while, and manually elevate PRV relief arm??? I DO SEE green H2O deposition on/around PRV. Could it be stuck closed by said deposition? Again, presuming it IS stuck, should I manually lift actuator arm???

3. "Third if the system pressure climbed that much either the expansion tank has failed, is improperly charged, or is not the right size. Could be a combination of all three."
I am uncertain as to which size expansion tank SHOULD be used. Again, though, the top 1/4 of the tank is warm, while the lower 3/4 of the tank are cool. Predicated on these observations, it seems to be functioning properly. Here again, though, I have no standards by/with which I can verify proper operation. Please note that I have attached photos of the tag on the bottom of the expansion tank, surrounding the nipple underneath. I hope those provide additional info for your reference!

Gordy

Is the proper x tank charge 12-15 psi verified isolated from system?

Inquisitor

NEILC, this post is in response to your request for a 'big/overall picture" of the piping, inclusive of circulator. The photos are self-evident. Nonetheless, I will take additional photos, explain further, if necessary!
Again, thank you for your continued interest, patience, and consideration of my issue(s)!

Inquisitor

GORDY:
1. "Is the proper x tank charge 12-15 psi verified isolated from system?"
I cannot verify proper x-tank charge. Is there a way to verify with air pressure guage? Unfortunately, for me, this is my very first intimate exp. w/an x-tank!

Gordy

Yes tire pressure gauge under that red cap. The tank must be isolated from the system though. Kind of hard the way it's piped. That guy didn't think about ever having to change the tank, or check it.

Inquisitor

GORDY:
THANK YOU FOR THAT INTEL!!! LOL. I had no idea what was under the red nipple! Yes, I actually already planned to install an iso valve after the heating season. It's easy enough to do w/double female iso valve. Cast iron 1" threaded males as it is now. W/SUATAINED RECORD LOW temps here, I cannot shut down to install. Well, at least not today. 40s will be here in cpl days. May be able to iso then!
QUESTION: IF NOT AT 12PSI, can I charge it myself w/compressor fill chuck, AND/OR DISCHARGE w/guage, if necessary???

neilc

that safety valve should be piped to within 6 inches of the floor.
right now, if it is to release, you have a hot mess all over the boiler at best ,
at worst it sprays you and that's gonna burn.
that said, I wouldn't touch it while it's hot.
why did you say you filled the system?
were you lower than 12 psi ?
leaking?
get that pressure back down to 12~15.

NY_Rob

Inquisitor said:

QUESTION: IF NOT AT 12PSI, can I charge it myself w/compressor fill chuck, AND/OR DISCHARGE w/guage, if necessary???

That's perfectly acceptable, but only charge your compressor to 15-20psi because the Exp Tank is small, you don't want to rupture the bladder with a sudden inrush of high pressure air.

Re the PRV, go to your local big-box store or plumbing supply house and procure a spare 30psi PRV. Many times attempts to "fix" them just result in greater leakage than before the repair attempt.

Inquisitor

NEILC:
1. "that safety valve should be piped to within 6 inches of the floor. right now, if it is to release, you have a hot mess all over the boiler at best , at worst it sprays you and that's gonna burn."
WOW!!! Now that i recall the plumber's last visit, he replaced the PRV, BUT, as you so eloquently indicated, DID NOT plumb it to where it SHOULD have been! Well, I can plumb that myself, once the temps warm up!
2. "why did you say you filled the system? were you lower than 12 psi ? leaking? get that pressure back down to 12~15."
No, the system was at psi, BUT, we weren't getting the expected, historic BTU output. All i did was open the auto-fill valve and allow it to fill until auto shutoff. I then went to highest point in system and bled out all air. The auto shut-off is the EXCLUSIVE reason why the system was operating at 40 psi, after boiler cycling. Further, NO, there are no leaks in the system.
☆☆☆UPDATE: I have now drained boiler back down to 15 psi. Also, I can now hear the H2O circulating through the pipes. Thus, at least, circulation is now confirmed. Extended thermo. observation will evidence better operation(or not-lol).

NY_Rob

PS... had the same boiler as you have OP... but the HC-100 100MBTU input variety.

I believe mine was installed when the house was built in 1963... it ran till I replaced it with a mod-con in summer of 2016.
It only gave 53yrs of service ....

Yours is starting to look a little rough around the edges, maybe time to start saving for a planned replacement vs. unplanned emergency $$$ replacement.

While it was a good boiler for it's day, it has literally no safety features whatsoever... just something else to consider.

Inquisitor

NY_Rob said:

Inquisitor said:

QUESTION: IF NOT AT 12PSI, can I charge it myself w/compressor fill chuck, AND/OR DISCHARGE w/guage, if necessary???

That's perfectly acceptable, but only charge your compressor to 15-20psi because the Exp Tank is small, you don't want to rupture the bladder with a sudden inrush of high pressure air.

Re the PRV, go to your local big-box store or plumbing supply house and procure a spare 30psi PRV. Many times attempts to "fix" them just result in greater leakage than before the repair attempt.

Inquisitor

Inquisitor said:

NY_Rob said:

Inquisitor said:

QUESTION: IF NOT AT 12PSI, can I charge it myself w/compressor fill chuck, AND/OR DISCHARGE w/guage, if necessary???

That's perfectly acceptable, but only charge your compressor to 15-20psi because the Exp Tank is small, you don't want to rupture the bladder with a sudden inrush of high pressure air.

Re the PRV, go to your local big-box store or plumbing supply house and procure a spare 30psi PRV. Many times attempts to "fix" them just result in greater leakage than before the repair attempt.

NY_ROB:
Thank you SO VERY MUCH for your consideration, patience, and response! FANTASTIC INTEL re: re-pressurization of x-tank!!! I DID NOT know that!!!
Again, thank you for your interest, consideration, patience, and response! ALL are much appreciated!

Inquisitor

NY_Rob said:

PS... had the same boiler as you have OP... but the HC-100 100MBTU input variety.

I believe mine was installed when the house was built in 1963... it ran till I replaced it with a mod-con in summer of 2016.
It only gave 53yrs of service ....

Yours is starting to look a little rough around the edges, maybe time to start saving for a planned replacement vs. unplanned emergency $$$ replacement.

While it was a good boiler for it's day, it has literally no safety features whatsoever... just something else to consider.

Again, thank you for your response. Indeed, we DO need a new one. If the hole-punched stamp underneath the x-tank is any indication of age (OCT-1978 punched out of sticker), it doesn't have long to go . . . AT ALL!!! Fingers crossed to finish this season!!!

Gordy

PS if you discharge the Schroeder valve and get water coming out its toast. I'm sure it's sized right if it has been on that long.

NY_Rob

Inquisitor said:

...Indeed, we DO need a new one. If the hole-punched stamp underneath the x-tank is any indication of age (OCT-1978 punched out of sticker), it doesn't have long to go . . . AT ALL!!! Fingers crossed to finish this season!!!

The boiler itself is likely older then the Exp tank, it's probably 1960's vintage like mine was.

With the lack of safety features on that boiler, it paramount that you have working/frequently tested CO and smoke detectors near the boiler, and of course elsewhere in the house.

Inquisitor

Gordy said:

PS if you discharge the Schroeder valve and get water coming out its toast. I'm sure it's sized right if it has been on that long.

GORDY:
Thank you for your continued interest and input! I won't be able to confirm proper Schrader valve functionality until I can plumb in the iso valve. Spring, if we make it that long!!!

neilc

if you're hearing flow, it's likely air mixed in,
is that air vent next to the expansion tank open and working?
Also, looks like the circ is pumping into the boiler, and torwards the Ex tank, that would be wrong and makes air elimination tougher,
consider either moving the circ to pump away from the tank,
or, and I'm not sure about this, maybe someone better can confirm,
but turn that pump 180 where it is, pump away from the tank and boiler.
If that was goofed when the circ was replaced it might also explain your missing BTUs.

Inquisitor

neilc said:

if you're hearing flow, it's likely air mixed in,
is that air vent next to the expansion tank open and working?
Also, looks like the circ is pumping into the boiler, and torwards the Ex tank, that would be wrong and makes air elimination tougher,
consider either moving the circ to pump away from the tank,
or, and I'm not sure about this, maybe someone better can confirm,
but turn that pump 180 where it is, pump away from the tank and boiler.
If that was goofed when the circ was replaced it might also explain your missing BTUs.

Hi, Neil. I feel like an idiot for having to admit that I'm unclear as to what "air vent" you are referring. Are you referring to the brass valve w/a flat arm on the x-tank side of it, just below the yellow-handled feed valve? Honestly, I don't know what that arm does. I just see that it swivels horizontally outward. Should I rotate it open for potential air release???
Respective of the circ., it's been in the same position for the past 27 yrs. The BTU loss is new, commencing w/the stretch of sustained record low temps here, over the past weeks, or so.