Hot water baseboard heating

baseboardheathelp

hot water baseboard heat

I would love an emailed analysis to give to them. I do not have floor plans or prints, but I could take measurements if that helps.  this is a 2 story 3 bed 2 bath house.  I do not know the insulation R values in the exterior walls and ceilings to any space without heat above.  was this something they should have told me, or is there a way for me to find out?  what should I be making sure they get tomorrow morning in the heat loss calculation?  I can post the results of that tomorrow, but it didn't sound like they knew what one even was.  we used a large company based right outside of Boston.  we heard they were good with steam...but they are definitly not good with baseboard

Steamfitter66

your getting a lot of good advice but...

at this point before they go any further and make a bad situation worse you need a competent consultant on site to properly assess the system. We cant responsibly do a heat loss calc from here. Also you will need a documented assessment of your system.

It really is not complicated most guys here can do it in there sleep.

Basic rulees of a proper boiler replacement are

1 Heat loss calculation

2 System design

3 Equipment selection

4 Proposal

5 Contract

6 Install



If you dont start with a load calc you can't accurately design and spec equipment.

Ironman

Correct head loss and pump size

The following is taken right from HTP's manual for the SuperStore, page 13, table seven. The table gives the head loss for the indirect, piping and fittings as described under G below. It does not include a flow check which would add another 2-4 ft of head. I added 3 ft. for it bringing the total head loss to 14.7 ft of head. I only copied the part of the table that matched your situation: 7 gpm, 11.77 ft. of head. The 7 gpm matches the output of you boiler at a 20* delta T which is the standard delta T.



I then ran it through Taco's pump sizing app. After adding the extra 3ft of head for the flow check for a total of 14.77 ft. of head, it calculated that a 009 was the correct size circ. See the attachment for the automatic calculation. Please note also that both the 007 & the 010 are not capable of any significant flow at this head; it's a no flow situation for both! If the flow check were removed from the equation, then a 008 would be the correct circ.



These are HTP and Taco's numbers.



G. PRESSURE DROP SIZING FOR CIRCULATOR

The boiler circulator flow rate must meet the requirements found in Figure 1 or the published ratings cannot be achieved. The flow chart below represents the pipe run, water heater, and heat exchanger ONLY and does not include any flow checks, zone valves, or friction loss through the boiler. That resistance must be added to the value found in the chart below.

PRESSURE DROP FOR PIPE LENGTH OF 1” COPPER, SIX 90o ELBOWS, AND ONE TEE.



7 GPM

11.77 ft.

PLUMMER

Forgetting some pipe in the calc?

The contractors equipment mix had me puzzled from the start as well. I like what Rich is trying to note from page 65 of the manual. I do think its is as easy as Rich posted. Truly when you have no clue these are the classic symptoms. "When in doubt go bigger", " the last boiler plate rating was that big". There were 007's in there before and they pump 30 GPM on this here chart."

baseboardheathelp

hot water baseboard heat

so someone came by to take measurements of the rooms, ceilings and look at insulation in our attic and basement this morning.  he is then sending the numbers to a 3rd party to have a heat loss calculation done.  I guess they do not crunch the numbers themselves, so we have to wait a few days for the result.  it is cold out today...10 degrees, and the heat is slow, about 30 or more minutes to go up a degree.

SWEI

HTP's numbers

Are unnecessarily confusing and do not tell the whole story.



The boiler circulator flow rate must meet the requirements found in Figure 1 or the published ratings cannot be achieved.



Figure 1 recommends a flow of 10 GPM for the SSU-45 and -60, which carries 141k or 171k BTU/hr of 180ºF boiler water.  Translation: 10 GPM will carry at least 171k, so they are assuming a minimum of 34.2ºF ∆T.  However, it will also carry 141k, so the indirect should also perform with a 28.2ºF ∆T.



The "chart below" (aka Table 7) shows 11.1 feet of head for that 10 GPM flow with 30' of 1" pipe.  It then shows 11.77 feet of head at 7 GPM, which I believe applies to the SSU-20 and -30 from Figure 1.  It can't apply to the SSU-45 and -60 if they have lower resistance at 10 GPM.

Rich_49

Grasping at Straws

Maybe we can help choose which ones to grab .  Here are a couple ideas , all of which I believe will work . Please post any thoughts .

From easiest to more involved .

1.    Change existing DHW circ.(007) to 0011 (boiler-13.4' @ 20 Delta , tank-9.1' @ 20Delta , 144' x 1" pipe) , change existing space heating circ to 0013 VDT . Disable ODR , set boiler high limit to 190* , set aquastat on Tank to 160* w/ 10*diff. , set Taco mixer at 115-120* . Pipe Tank with supply into top port . Leave wiring as is

2 .  Eliminate DHW circ altogether . Add Taco ZVC 403 and a third zone valve for DHW (1") , wire aquastat to zone 3 , set aquastat to 160* with a 10* diff., set Taco domestic mixing valve to 115-120* , make this zone Priority . Pipe tank with supply into top port .

 Install 0013 VDT to handle domestic and space heating . Disable ODR , if in fact it is in operation now , does not seem that reset is an option for this one due to poor performance at present , set boiler high limit to 190* . Change wiring accordingly .The system will operate at a respectable 85%+ and all will be good .

 3.   Cut and cap DHW loop from present location , move to inside of boiler loop  and pipe and pump as per page 64 and 65 notes and illustrations ,  keeping DHW loop as short as possible of course . Set boiler high limit at 190* , enable ODR , change space heating pump to 0013 VDT , possibly 008 VDT if piping for heating circuits allows ,  set tank temp at 160* and mixer at 115-120* . Pipe supply into top port of tank .

    Please check me on these options folks so we can offer her something to hand these fine gentlemen so they may make her whole .

RobG

unbelievable!

An HVAC company cannot do a heat loss on their own! Did you get a copy of their findings on room size, insulation, etc.? If you can post that info here we can verify (approximately) the heat loss. Just to keep them honest.

Please let us know.

Rob

Weezbo

That is beautiful, baseboard heat...

here is why ,

they are taking measurements .

..........................................................

and you are taking observations



..............................................................

so when we walk into a ten by ten room,

with 10 feet of base board,

and a boiler and a circ ,

and see some gauges,

and have a watch ,

and have a means of determining the room temp from a known temp at the same point within a room,

and knowing the transfer rate of a pump in gpm,

and knowing the heating emitter output ,

and knowing the out door temp,





we can begin to know where to look for the variables ....



one of the first is we can determine direction of flow.



or if there is flow or if the appliance is producing heat .

Rich_49

Weezbo

think I should add some gauges in the remedies so these gents can see how a system reacts and how temps , flows and pressures change within a system ?

Maybe a well planned trip to Cranston for Barba's Advanced soup to variable speed nuts course would be a great help to these guys .

baseboardheathelp

hot water baseboard heat

we did ask if we could have a copy of the results/measurements, and he said he could not give us it and would have to ask his manager first, and that we could get a copy of the heat loss results when they come in in a few days.  once I get those results from that 3rd party they send it to, I will post it.  I know it's very cold out here today, but the heat is struggling to heat the house. 

baseboardheathelp

hot water baseboard heating

the last 2 days, when we have turned on the faucet water, it has come out with a slight brown tint for a few seconds before getting clear.  this just happened now in the Kitchen on warm water, and yesterday on cool water.  is this related at all to the heating instalation, or a completely new and separate issue?  the timing is a bit odd, so I thought I would ask

Rich_49

Probably unrelated

to this install .  If it was only on the hot water side it would be suspect but since both hot and cold have shown the same condition it is probably something other .

Weezbo

Absolutely .

if you come into a boiler room that was not doing this, and not doing that, where are you going to start.?



.............



i am warming a strap on gauge on my by pass and am considering mailing one to the lady as a Christmas gift from the North Pole , with a deed to a square inch of land for her as a something to remember the year when santa sent her a gift...



..



Knotgrumpy , suggested an infra red heat gun like the ones we enjoy . would be an easy and inexpensive means for her to verify some things a week ago ...

or more.

at 20$ your price at a big box store , it seems quicker and easier ....however , with mailing it to her the next episode would be one where we could ask her to put the gauge on the supply pipe or return when.....



and get the real idea of flow /Temp and what direction under specific conditions .



.... that would speed up trouble shooting exponentially.

i just solved three separate issues over the telephone involving radiant heating boilers and admin questions this last three hrs...



and the last call offered to let me buy him lunch for helping him ...lol i have some Great friends : )))



they always say things that are totally non-sequiter which seems to suit my sense of humor ....



... any service man can determine the flow , or the pump's functioning the mixing and boiler's out going and incoming temps and make quick conjectures as to what next to look for as he goes down a check list . : zone valve operations , sensor operations ,control operations, transformer operations ,all that good stuff.



........



*~//: )

i offered to lend him my pex thaw tool he declined as he made one after the last time i went out to help him work on some Dr's home ... however ,

he called back ,....during my having just replying to you..



right now , he is coming to get my purge pump/ transfer pump with the dirt cal from Caleffi lashed up to it ...



....

Rich_49

Weezbo

I see that you are awake and just posted . Please have a look at the 3 possible solutions , I believe any one of them will work , and let us know what you think about them

Weezbo

let me in there a moment...

hand me that pipe cutter , lol..



the temp gauge on the by pass reads 60 C or 140 F ...



'think this is working properly....'



the reason i am trying to get a glimmer on this temp reading info is so i can determine what is doing what ... i like to do that first because then the least invasive procedure can be obtained .. if we take to designing her system when we have seen perhaps only one of the problems and without having a clue other than a connective couple zones of base board seems too habby to end up redesigning the entirety piece by piece ..



two zones 114 / 2 = 57 ' when divided in half ...



so , now ... before we even touch the header and spin in two 6 foot lengths of 1 1/4 direct to the water maker ,with the cleanest straightest lowest friction machine formed offsets and bends , to female reducing adaptors .... lol



knee knockers close coupled like that to the primary i would say insure max efficiency with DPO off a parallel primary .... and digital read outs for DT ,



...thing is what good does that do the installers if we know that and they might not?

and when we make the heat plant function as zippy as that for hot water production,



are there any other considerations ...?



so , if we ask the question we basically already Know the answer ...



Mark suggested a couple other minor technicalities Earlier on as well that i thought were more than reasonable and subtle /observation suggestions ...

my little pinner dawg wants some munchies Brb...

Weezbo

i can see you have looked thru ,..

some options and considered many thinggs on the fly and have done some phone tag , pencil pushing , button pushing and numbers crunching and some leg work to run some things down as well....



please dont take me wrong on this buh there are still some more things to be considering ,

one is this , i have 4 rooms all the same with all some how absolutely = heat loss in every way , now , i have ONE zone on that entire floor ...



so i start someplace , the North E. corner of the North wall.and wrap the entire outer perimeter of all outside walls with equal amounts of baseboard .



the first two rooms are wrapped and the here is the consideration by the time i get to the end of this line of heating all the way back around to the N.E. corner ...and bang it to the boiler straight down , with 196 feet of baseboard 44 feet in every room ,

how is this going to preform , .....

lousey right . so i see it has a 007 in the boiler room yet i havent even seen this pipe done by my alter ego self just yet ...i am only looking at the boiler room ..



so i start in going This thing is stupid it probably is a bad pump..

so i will bring in my new one and that ought to make it go...it is not ever going to go and the system still wont go with the new HV0012 lol...

whatta peiec of crappola ..lol

no,

it has a considerable amount of base board on this circuit , not only that , the base board is seeing one temp on one end and one on the other now that we have two 26-99s in series lol..



lets just say for now that this arrangement of circs was the "Correct one to move the frozen ice out of the pipe ...:)



we have been looking at the boiler room with no information for weeks before we hit on well, time for me to look upstairs and leave this pOS running till i can get some "Recon" info with my tape measure ifr gun and some WD-40 because it is squeaking and popping and crackeling something fierce up there...



OH my ! we got one loop! oh O !

..........................................................



ok new senario same house same sorta deal except this time room one has 12 " room 2 has 14 room 3 16 room 4 20 ok

62 feet of base board



why did the guy have different lengths and still pump with too much base board on the loop?

/ zone ? this one the heat loss was lower , yah ok maybe...buh why so much discrepancy in each room?



he is trying to make up for some other minor technicalities and it was a good thing you saw this before thinking maybe the return meant that the circ was having some problem with the impeller or something...



now here comes joe home owner and says well now we have what seemed like even heat all the time until yesterday... no gauge no nada in the boiler room ,

so you go back and think about that for a moment.....Hmmm.... that is different ...



so now they say buh you know what ? the top floor is always a Hassle,

too hot one time ,

too cold the next ,

and never can tell if the small sewing machine room is going to be ever seeing any heat ...

it is piped something like the first example buh this time whoever piped that was a completely clueless guy he has 2 feet under a window in the sewing room and it is like the last piece of radiation on the return....he has just put base board wherever he thought seemed like a good idea when he was working on the place ...

he has 12 feet in a closet and 30 feet in one room on the inside partitions and 14 feet on the outside wall in that one room alone ! no Wonder its all over the place and the folks been leaving the door open to see if they could get it to equalize out a bit as they said to you earlier over the phone lol...



i know that you want to offer the guys some decent way to proceed with the parts and pieces and get them "Choose One!" at least you will have some GeeDee chance to get this thing right! lol;)



er... oops ! lol..

i get that ... i honestly do.



i think adding more things right that are code every time , and provide us with more information rather than Hidden Discoveries cropping up that then in turn make us reconsider yet again , ,....at first i was wondering about how This particular lash up was managing to Pull from both directions from the tank and considered well , maybe these guys busted their brain cell devising some specialized mixing and had invented a type of mixer using the controls,

i could not speak to that straight out all i know is some how the pipe arrangement changed and suddenly things changed for the better apparently buh

that was what i wanted to learn about the Rangeability of that particular arrangement and how it works on the control and how that functions on a call for heat and then differently on a call for DHW in a different manner ....where suddenly it throws off that particular advantage and transforms to act like a parallel primary ....



that seemed like one heck of a Trick and i was looking to hear some feed back so i could understand that.

i am going to search for an old post and it is having a picture of a zone valve on the return of a hydraulic separator mounted on unistrut up near the ceiling ...

it is something 180 degrees out from this deal we are discussing ...we have a day or two .



and it is about persistence in the search of excellence ...

for now on another note the slant fin plate exchanger water generator has a 0011 on it with a 1/2" feed of potable water , seen any of them in your travels?



.............

Weezbo

Rich,

i stayed at it until i was passing out re reading old posts and never found it .:(

it is among the very best of puzzles we ever had a chance to see .

.

the base board heating in this home , might be about 60 ' long per loop .



i don't find that particularly great.. while it is possible to get better or lower temps out of baseboard what i mean by over sizing the baseboard (Lengths) is relative to the room not the entire zone .



a quote comes to mind , " wife of 40 not equal to two twenties."



baseboard is like that , were there two zones with them each being 30 ' run off of manifold then even if 20 more feet were added or i should say shared on each zone equally i would consider that being able to deliver the btu's much more effectively at a lower supply temp .



once again the extra would be relative to each room ...



so if we knew what the supply and return water temps were then and what they are now that might have told us even more information .



granted the numbers are only a snap shot in time .



This new set of numbers on the test of the hot water and the brown tint ...

ok well, if the house has a 1/2" main and the pressure went up that day because of a completely different issue involving the munis New Pumps selection ...

which temporarily drove the house water pressure up because of older aub blow by ...normally the muni would be quickly notified and go Oh o! send someone down to the pump station and get them to dial it back we are getting nuisance calls about over pressure.

for an example . the aub 75, is supposed to regulate the pressure , yet it may have been set at a lower supply ,... we know this could happen, although ,it may not have been exactly that ...

we are not on that job so we cannot go over to the regulator and re set the pressure right quick . my thought is i'd dial it down to 50 Psi and check it first ...

sudden higher pressures show up as aggressive abrasion within a line and preform a scouring of the pipe and fittings like erosion corrosion from way oversized circs moving air bubbles .



which brings us back to your idea to give the guys coming tomorrow one some other options Choose One and go with it : )



they seem on this new tangent though of getting a New and Improved Bigger Hammer ,...let me in there how bout handing me my 24" crescent yah the twenty pond crescent...lol



when we work on increasing the system side efficiency we do ourselves a huge favor because that's one more person and their family that will have a better outlook in our community .

i just burned and hour Rich discussing trv's and pressure differential and thermostatic by passes while typing this out.. avec a dash of outdoor reset

and aluminum plates on the runouts to and from some panels .



i hope these guys take the time to read what we have been saying , everyone including other homeowners chirped up to aid in the conversation ...



there have been extraordinary replies that offered superlative real life experience and suggestions , technical ideas threaded around the theme that everything is within the realm of being approached by reason .



i need my "all amazing seeing eye" to determine what is going on inside those pipes and unfortunately its in my old one ton ... so we had to go looking for what is wrong rather than what is right to find ways to suggest some solutions .

Weezbo.



i am sad for that.

PLUMMER

Most important issue learned here

Was what we learned about the installing contractor and the reps (actually salesmen) that came out. The responses given make it blatantly obvious they shouldn't be allowed to touch radiant. The most basic steps were skipped. Like the heat loss calc they should have done before turning in a quote. Back when I was learning I was lucky enuff to have one of the best salesmen helping me and our customers. Proper sizing and engineered plans were always used and started with. Mr. Rizzo was one of the top RPA guys for our district, a very outgoing helpful man. But this was exactly why we got more jobs and in many cases got much more money for the job. An informed customer was my best client, as they too understood why all these other parts and components were necessary for a properly functioning system. Mr. Rizzo made me look smarter than I was.....haha.

This also weeded out a lot of the uber cheap customers that eventually turn out to be. Nightmares. And you also get the one that bleed you for info. It's ok cuz even with plans those would still get something wrong.

I hope all is going better now

baseboardheathelp

hot water baseboard heat

heat loss calc came in, and they said that we have enough baseboard in the house and that the 80 is sufficient.  we told them we will not let them put in the 105.  they are coming back tomorrow and reversing the piping that needs to be fixed at the bottom of the HTP, slowing down the water pressure with a valve, and putting in a new Tacor pump.  they are coming with the 0010 pump.  which pump at this point should we tell them to bring?  I know there has been some different suggestions posted...I have seen 1 reply saying that the 007 is right, a few said the 008, a 011, and  0010 prior based on the manual.  all we know is they finally agreed to remove the 007, so which one should we insist they put in.  they are saying HTP rep told them 010

Rich_49

Pump

For the Hot water should be a Taco 0011 . Boiler head = 13.4 ' @ 7.3 GPM (Burnham Manual) ,  Tank head (as per HTP being given the correct information by me) is 9.1' @ 7.3 GPM , Better yet , you can call HTP and give them the following information so you cannot be lied to by this contractor .  Call HTP , connect to technical and ask the following . " I have a system whose boiler has a head loss of 13.4 feet at 7.3 GPM , 144 total equivalent feet of 1" Type M copper and an SSU-45 indirect , what Taco circulator do I need ?"    HTP will give you a ticket number and you should ask for one , this will verify that you called and spoke with tech .

   As far as the heat loss goes , did you or can you receive the detailed results ?  Request them so we may help get your heat straightened out also .

baseboardheathelp

hot water baseboard heat

ok thank you.  I got the heat loss calc last night.  It basically has measurements for each room in th house.  it put the indoor temp at 70 dgerees, outdoor at 3, and system design hot water at 180. 1st floor heat loss at bth/hr is 31, 742, job total 45, 012.  2nd floor heat loss 13, 270, same job total.  baseboard for 1st floor in fine/line 30 (lin/ft) is 56.5 and 2nd floor is 23.5. floor factor .09 on 1st floor, 0 on 2nd floor. infiltration factor .018 on 2nd floor in all rooms, and on 1st floor same thing, except 2 rooms have a .012.  I have lots more numbers.  just let me know what else you need. 2nd floor ceiling factor .05.  I have exosed windows/doors per room as well.  I can post the results,  but it may be too small to see. let me know.

Rich_49

US Boiler Tech

John from Tech at Burnham (US Boiler) just informed me that the boiler pump in fact does not have power interrupted on a call for DHW . I asked why the manual online shows that and piped off the boiler loop and he is looking into why an older manual is available online on the site . . That being said , now that all parties have been contacted and the proper information gotten to , if they switch the supply and return on the tank and change the 007 to a 0014 or 009 ( either will work , 0014 has a bit more head available) you should then be in fine shape .

Are you able to scan the heat loss report and attach the document so we may see the numbers as they appear on the report ?  We would also benefit by knowing how much baseboard is installed in each of the rooms .

baseboardheathelp

hot water baseboard heat

oh boy.  they came with a 0010, and I gave them HTP phone number, and

they said HTP is saying to get the 011.  he just left to go pick up the

011 pump.  will this not work now??

I can see if I can scan the heat loss calc today.  in terms of baseboard per room, infine/line 30 in, the numbers are 18, 8, 14, 8.5, 4, 4, on 1st floor, and on 2nd floor, 7, 5.5, 5.5, and 5.5. does this help?

Rich_49

0011

will be fine . I apologise for not calling Burnham earlier to verify sequence of operation and logic on this boiler , their manual that is available online may be older as John from US Boiler stated that any installation off of the boiler loop si no longer recommended in the current manual . He could just be out of the loop however . We must take his word on this though .  You are finally on your way . I guess they never did speak to HTP then ..

Those footages will be fine once we match them to what room each is installed in and can view the heat loss . Maybe you could give us the BTU requirement for each room from the report and how many fet are in that room . That may just do the trick .

baseboardheathelp

hot water baseboard heat

so they put on the Taco 0011, reveresed the piping on the HTP, and still, cannot fill the bathtub wiht hot water. still runs out at 6.5 min, about 25 to 30 gallons of water.  the heat went up about 2 degrees in 1 hour 20 min.  it lost 3 degrees when turned off over an hour.heat loss but/her 2nd floor-per room, 3870, 3180, 3006, 3213, and measurements per room (height, lenght, width) in same order are 7.5 by 11.5 by 11.5, 7.5 by 11 by 10, 11 by 11 by 8, 7 by 11 by 12. 1st floor: 10 436, 4470, 8129, 4697, 1991, 2019, and dimensions in same order: 13 by 15 by 15, 8 by 12 by 15, 8 by 20 by 12, 8 by 12 by 10, 8 by 9 by 10, 8 by 9 by 10. let me know what you think, and if you need more info.  sounds like they are tying to say with this burner and ssu-45, we should not expect a full tub of hot water, and they still think the 105, but using the same tank this time, will give extra heat recovery and could work better.

baseboardheathelp

hot water baseboard heat

also, what are your thoughts on this: http://www.htproducts.com/literature/lp-83.pdf

my brother found this.  page 9 table 5 below it, it states that the boiler required to get the advertised numbers needs

to have an output of 141000btu/h.  Mine is around half that. thoughts now on a bigger boiler?

 

SWEI

The advertised numbers

are basically the maximum amount the indirect can absorb from a boiler.  If you really need that kind of DHW output, you probably need to rethink your DHW heat source. Your current boiler produces roughly two and a half times as much heat as a typical gas-fired tank water heater can.



Your building heat loss was calculated at 45k.  The minimum firing rate of your boiler is 16k.  I would not recommend any boiler that has a higher minimum output.

Steamfitter66

How big is this tub.

On small mod cons I typically use an 80 gal if theres a garden tub or body sprays, 60 if not.

All this trying to get the correct pump is for not if the boiler cant supply it. What I mean is there is very little performance difference between 4 gpm and 8 gpm if you only have 72000 btus available from the boiler. A flow chart and gauges would have told them this.

I think you may need both the larger boiler and IDWH.

If you have an 80 gallon tub and want a 60 gallon 110* bath fill for net 105 water and your incoming water is 50* the water heater will need about 25 to 30 min of the boilers time when you factor in set point lag and line loss. Take a shower before hand or do laundry and you could be off for a while.

Your house is cooling of more than you like in that amount of time. I'm all for properly sized equipment but if the have checked gas pressure, clocked the meter and have done a combustion efficiency test, then your ready for some larger equipment.

baseboardheathelp

hot water baseboard heat

it's a typical bathtub from 1998.  probably about 35 gallons or so.  so one of you is saying get the bigger 105 Alpine, and the other post to stay at the 80?  I just want to make sure I fully understand 

RobG

Clocking Meter

Someone needs to clock the gas meter to see if the boiler is actualy putting out its maximum  output at high fire.

Rob

Pughie1

priority

I've lost track, is this system still set for prority DHW?

John Pughe

baseboardheathelp

hot water baseboard heat

yes it is set for set for prority DHW, and they did clock the gas meter,  they are out of idea, and talking about flying reps/engineers from PA here form Burnham

SWEI

Talking about flying?

This isn't rocket science.



I guarantee that someone at either Burnham or the MA rep knows a truly qualified contractor located near you whom they could hire for less...

baseboardheathelp

hot water baseboard heat

I agree.  we should hear back from them in a few days.  They reduced the pressure to 65 pounds by putting in a pressure valve, and that gave us abou an extra 40 seconds of hot water in the tub.  he has an idea that possibly a buffer tank coudl help.

SWEI

Numbers

What temperature is your incoming water?  How many gallons to fill the tub?  How hot do you want the water in the tub to be?

baseboardheathelp

hot water baseboard heat

about 35 gallons to fill the tub.  last time they took the temp of the incoming hot waster it was 118 degrees.  I could go up a few degrees though and be happy.  I will buy a thermometer this wknd and measure the hot water coming in myself

SWEI

Is this a cast iron tub?

118ºF is far too hot to bathe in.  Your 45 gallon indirect should be able to fill that tub without delay, no matter what boiler is hooked up to it.



Any chance they reversed the DHW inlet and outlet ports on the indirect?

baseboardheathelp

hot water baseboard heating

I will buy a thermometer and take the bath water temp.  are teh DHW inlet/outlet ports what is on the bottom of the HTP?  if so, yes they originally reversed these, and they corrected it today.  it is not a cast iron tub.  I believe it is plastic?? 

baseboardheathelp

hot water baseboard heating

so on the hot water tank, I turned on the hot water, and for the pipes on the side of the HTP, the pipe at the top got really hot, and the pipe at the bottom got really cold.  I'm guessing these were the inlets you were asking about.  are these correct, or is this reversed?