Amateur DIY hot water boiler install on old gravity system with steam boiler attached (long story..)

PC7060

I doubt you’ll need it, the HTP units are pretty much self contained. 

Did you get a EFT series?

gchrisman

Yes, the boiler I ordered is an EFTU-110WBN. Planning on doing a primary/secondary piping configuration with a single Taco system pump and effectively a single zone with one central thermostat.

mattmia2

That is the type of 2 pole contactor you would use for an AC condenser. I don't know what you would use it for with a steam boiler. Even with a hot water boiler with old 3 piece circulators it would be overkill.

PC7060

@Ironman has done several of those units. IIRC he recommended buying a spare internal pump since it’s a proprietary unit (built by either a Grundfos or Taco)

JUGHNE

Some Mod Con boilers can handle one pump, the second one is pushing the fuse rating.
I use a pump relay for the second pump. For instance a RIB relay with 24 vac coil.
That relay you have would work if a 24 vac coil.

hot_rod

A basic switching relay, with a 120V coil.

gchrisman

I have the boiler installed and piped (lots of sweating copper pipe together - I'll post photos soon), did the venting and wiring, and then began to flush the system as suggested above. I got the water running clear, but the process revealed multiple leaks - most of them at radiator valve unions. I had replaced every valve in the house, but not every spud. Reading through this site now on that topic, I realize this was a bad move - though I remember how excited I was when I found a brand of valves (Bluefin) where the threads matched up with my old radiator spuds! So much to learn...Now I have to go back and change out all of those spuds. This process is quite challenging, since the radiators (massively heavy) have settled into the floors slightly, and things don't line up perfectly anymore. Even when they do, the fit is often so tight that I'm worried about damaging the union faces when I try and get everything to fit together. Any suggestions? Should I cut away some of the flooring (how?) to make room for the pipes to flex away from the radiators? On some of the radiators where I have to cut out the spuds (very likely) should I just plan on removing the whole reducing bushing instead rather than risk dealing with damaged threads? Should I go back to the few where I did replace the spuds (often having to cut them out with a jab hacksaw) and replace the reducing bushing there as well, just to remove the chance of a leak in the future? I can already tell what a pain bleeding the whole system is going to be, so I want to set things up right as much as I can.

PC7060

Leave the bushings alone, I can’t see how you’d get them out anyway.  

Always replace the spuds and valves as a set; that’s the way the part is sold anyway.  Spuds typically come out with a spud wrench and a 18” pipe wrench (and maybe a cheater bar). I’ve occasionally have to cut the nut off the spud and then use a 2’ pipe wrench directly on the spud to break it loose.  

You should consider installing TRV instead of standard valves. Very nice when tuning temperature room by room. I used the original out flow 90’s.  Something like 19 radiators in my house; original 13 plus 6 “new” old radiators for the 2 bed/2 bath + kitchen addition. 

mattmia2

Find a piece of rod or at least pipe that fits inside the spud to keep it from collapsing if you try a pipe wrench on it after you have sheared the lugs off.

You could also try an inside pipe wrench similar to this:
https://www.supplyhouse.com/Pasco-4512-PASCO-3-4-Internal-Nipple-Wrench

gchrisman

I got all the spuds replaced in all the radiators this weekend. I used a few 2x4s and such to move the radiators around while I worked on them - hard work! Here also are some photos of the near-boiler piping. I know it's a bit of a mess, but don't be too hard on me - it was my first install!
I haven't had time yet to fill the system or test for leaks again, but I really hope I don't find any more...

JakeCK

Are you you putting together a temporary solution for the winter?

gchrisman

I really hope to be able to get the boiler and radiators functioning - but if not, I'll be using freestanding electric radiators.

JakeCK

No I meant is the near boiler piping just to get you running for the winter?

gchrisman

I was hoping the copper pipes were good for the long run. The PEX is obviously easy to change out if needed. Some of the PEX routing is less than ideal, I'm sure.

pedmec

i hope this is just temporary. and i don't just mean the pex.

gchrisman

Any helpful suggestions?

GGross

@gchrisman

For starters that gas pipe cocking out at a nearly 45 degree angle away from the wall is not very good. I see what you did there, just swinging the gas line from it's old position back to where the flex line will reach.... Needs to be straight and secure, that's the primary thing that has me concerned here, the gas line, looks like it is hitting the cold fill line, which will most definitely vibrate if it ever fills the system.

Your relief pipe is hanging by some plumbers strap, its gonna kick around if it ever blows off, not very safe.

I thought these boilers needed an external low water cutoff? Maybe it has a flow switch built in?


The other piping of course is not straight, secured, or anything, if it works it works I guess. Shouldn't really use the poorly secured lines to hold your power cord in place, your circulator power line needs to be secured tightly to the wall.

I am going to be 100% honest, this is the worst diy install I have ever seen, you really need to call in some help on this

JakeCK

I didn't want to be the first to say it but yea. That is bad. I doubt you'll even be balanced in the least. Good chance only half your house will heat with that. That is unless you want to stand in the basement turning those ball valves on and off 24/7.

And I can't tell from the pictures what direction that gas line is coming from but there is a chance you actually loosened the threads when you swung it over to the new boiler. If so you could have caused a leak. When dealing with black pipe if you ever have to back it off you run that risk. At least that's how I was taught by the old navy fellow taught me how to thread pipe.

I don't want to say throw in the towel but you still have a lot of studying to do before you'll have a good system. And it is way to late in the year to start now learning all that now if you want to have good heat in a few weeks.

gchrisman

Believe me, I tried to find help around here, but if you go all the way back in the thread you'll see what kind of 'help' I got. At this point, I'm just trying my best, and appreciate all the help/advice I can get.

The boiler does have a cutoff switch built in, so according to the instructions I didn't need the external low water cutoff.

I can certainly reroute the gas line - I've done that before. Same with the electrical wire, which is probably long enough to go along the wall.

In general, it sounds like most of the issues you are seeing are with securing the various pipes? I am brand-new to this, and just not familiar with what is normal when it comes to things that aren't shown in the abstract diagrams of pipe layout. How would I secure these pipes to the brick wall?

gchrisman

As far as balancing the system goes - what did I do wrong that will make balancing difficult? I do have a bunch of ball valves in there, so I assume it has to do with the routing or setup of the pipes? Any suggestions about how I could make it better?

mattmia2

Is that pex oxygen barrier?

I would use more fittings in the pex to make it turn where you want it, with it both being inherently in a tight space because it is near the boiler and because it is large it will be almost impossible to do what you need to do just bending the tubing. Plates screwed to the wall and threaded rod and rod type pipe clamps are a good way to secure things. Rode clamped to usnistrut screwed to the wall using a channel nut, square washer, and a nut is another way if you can get all the support in one line. Some more copper until you are further from the boiler might help, cut out the pipes that were fitted to the old boiler and adapt to either pex or smaller copper and get them heading toward the new boiler.

Does that boiler have an internal circualtor? Read the manual, but unless it is using its own circualtor, you probably only need to use one supply and one return tapping.

The relief valve line can not be threaded on the end so someone can't screw a cap on it.

GGross

@gchrisman

Generally the built in low water cutoff devices are an additional safety, around my area the code official still wants to see an external LWCO where they have an internal LWCO. Flow switches whether internal or external are considered acceptable in most cases, though I have heard certain jurisdictions still require the external LWCO. I would plan to add an external LWCO to your system.

Generally what I have done and seen done, is to secure a piece of unistrut to the wall, and then secure to that. You may have an opportunity to test drive the heating system to see how it heats, I do think you could have balance issues however hydronic systems are surprisingly forgiving to goofy piping... until they are not of course. I would focus on the safety issues mentioned first, and any others that other people may find first.

My concern is with that gas pipe, as was already mentioned if you kind of swung it back to the boiler it could be in bad shape at the threads, if you secure it at the ceiling above, and make it straight, coming straight down to the boiler you won't need much additional for support

gchrisman

The PEX is oxygen barrier stuff. It came it a massive roll, which made it very hard to straighten out - it wants to stay curled up, which is part of why none of it is straight. Those flanged fittings that connect to the original piping - are those fittings I can take apart and bolt back together without replacing the gasket? If so, I can just rotate them to get them aimed better, but I didn't want to disassemble them and then not be able to replace the gasket.

I can cut off the end of the relief pipe if it shouldn't have threads.

The boiler does have its own pump in there, and it only has one outlet and one inlet.

Will do on the gas pipe. As to the LWCO, one of the few benefits of living in the boonies is that we don't have any inspections, so as long as the internal one functions, I may be OK.

I do have manual valves on every radiator to help with balancing.

I'll look up the materials you suggest for securing the rest of the piping.

PC7060

I’d have positioned the HTP unit under the supply and return lines.  It would have simplified the routing.  

I had the do this for my unit and it came out pretty well although the ProPress was key to a clean installation. You may able to find some one with a ProPress to reroute and clean up the routing. 

mattmia2

You can also get that in a floor standing model which might have been easier than building a wall to hang it on.

PC7060

mattmia2 said:

You can also get that in a floor standing model which might have been easier than building a wall to hang it on.

But there’s two side to every wall! 

JakeCK

gchrisman said:

As far as balancing the system goes - what did I do wrong that will make balancing difficult? I do have a bunch of ball valves in there, so I assume it has to do with the routing or setup of the pipes? Any suggestions about how I could make it better?

Water is lazy. It will take the path of least resistance. A large enough imbalance with regard to resistance to flow will stop it from going to one or more zones in favor of one with much less resistance. Old gravity systems were true masters of physics. Large headers and mains that incrementally got smaller as you went down the lines to each rad. Everything was pitched back to the boiler so the hot water coming out the top of the boiler could naturally rise with convection currents and the returns slopped so the cooler water could naturally fall back to the boiler. With introduction of circulators that no longer was necessary but you still need to balance or have some kind of control over it if you have a single circ.

gchrisman

I followed a lot of the suggestions here for re-piping things and securing the piping. I fixed the gas line. I also found a bunch of leaks nearer the radiators and replaced that piping as well, including two second-floor risers that had split because of rust or freezing.

I flushed the system, found more leaks, and fixed them. Two of my radiators are a different style and have no bleed valves, just stuck plugs - I simply shut them off for now, and bled all the rest thoroughly. I finally got it to the point of real testing, and filled the system to 30 psi for a few days. That revealed a single pinpoint leak in one copper pipe joint, which I have patched for now. I ran the purge cycle on the boiler twice. Last night I reduced the pressure to 18psi and tried to fire up the boiler for the first time, and ran into an issue: the HTP boiler lights fine, and the temp increases initially. The internal pump and the circulating pump both turn on. However, the outlet pipe only gets hot up to its close-spaced T immediately below the boiler, and the heat doesn't move beyond that. After a minute or so, the boiler gives me two codes: first a warning, IP2, which says it means low circulation, and then it shuts down with a 105 error, which is also low circulation with a significant temperature differential between the outlet and inlet.

Since my circulating pump is a Taco 0015 3-speed, I've tried this using all three speed settings, with no difference in the behavior of the boiler. In each case, after the boiler shuts down, the heat spreads out a little ways beyond the T.

Things that come to mind: the primary/secondary piping doesn't seem to be working correctly - should I just re-pipe it directly instead? Or, is the circulation pump substantially under-powered? Or, are those two un-bled radiators causing an issue, even with their valves shut down? Any ideas? Thanks for the help! I know I'm a rank amateur, but I do really hope to have this system produce some sort of heat this winter.

mattmia2

Is the supply to the system getting hot, the supply side of the closely spaced tees? I dont see how a big delta t is an error on a high mass system on a cold start assuming that heat is going out in to the system. If you shut off the system circulator does the boiler loop get hot? The boiler loop/circulator could be air bound.

Peter_26

@mattmia2 has mostly likely solved your problem!
@gchrisman did you perform the air purge as described in the manual below?

The boiler and heating system must
be thoroughly purged of air during
the initial installation or system
maintenance. Proceed as follows to
purge the boiler and heating system:
1. Open the air purge valve inside
the boiler. The valve is already
connected to a discharge hose
routed to the condensate trap.
2. Gradually open the main water
valve until water flows. Do not
open fully.
3. Thoroughly purge each zone
starting with the lowest point and
close them only when clear water
free of air is visible.
4. Close the air purge valve when
clear water free of air is visible.
5. Continue filling the system until
at least 12 psi registers on the
pressure gauge.

gchrisman

Yes, the supply side of the boiler is getting quite hot, right up to the closely-spaced T - at which point the temp drops abruptly, and I can touch the bottom of the T with no problem. Maybe there is an air bubble in there somehow...

I did run that purge/bleed cycle, with the exception of two radiators that don't have bleed valves - and those radiators' valves are turned off. Could those two radiators (one is on each loop of the system) be causing the trouble?

I did bleed the air off the boiler itself using that internal valve - I did it a few times to be sure.

mattmia2

Does the pipe going off the closely spaced tee out in to the system get hot? If it is getting hot then there is circulation out in to the system. If nothing is hot beyond that then there is no (or little)circulation through the boiler.

Is there a strainer somewhere in the boiler that is clogged with pipe dope or rust from the old radiators?

gchrisman

The pipe going out to the system from the T does not get hot, just the supply pipe connected directly to the bottom of the boiler. I think the error is coming up because there is no circulation happening through the boiler. I don't know if there is an internal strainer in that boiler, but I'll certainly look into that. I'll check the external dirt strainer, too, but I don't think it's clogged - water was passing through it just fine a short time ago when I was flushing the system.

mattmia2

Are you sure you have it wired and configured correctly to make a domestic heat call when your system is calling?

gchrisman

Pretty sure - when I turn the thermostat up over the current room temp, the boiler does light off and the CH indicator lights up, showing a level three burn (it has 5 levels for the burner, which are selected by running a calc between an outdoor temp sensor and the current thermostat setting). It runs for a minute before giving me the error code, but it does trigger correctly from the thermostat whenever I have the error reset. The external circulation pump turns on as well.

mattmia2

Does the internal circualtor run? What state is the 3 way valve for the dhw in? I think there is a status menu you can get in that will tell you the state of the various things. The info in there should help you figure out what is going on. You can also call or e-mail HTP's tech support.

gchrisman

The internal circulator does run - it has a light that comes on, and I can hear it, too. The 3-way valve: the manual told me to disconnect it when not using the DHW function of this boiler, so I simply unplugged it. Maybe that is the issue? Perhaps it is in the wrong state (DHW instead of CH), and can't switch it because it is unplugged?

I'll reach out to HTP as well. It is seeming like it could be an internal issue to the boiler.

gchrisman

The HTP guys confirmed that before unplugging the 3-way valve, I should have used the controls to manually set it to CH mode, then unplugged it, then set the manual mode off. Of course, none of that is in the manual - just the bit about needing to disconnect it. I'll try what they suggested as soon as I get home this evening, with my fingers crossed!

gchrisman

It worked - I had to plug the valve back in, enable manual control, set it to heating, then unplug it and disable manual control. None of that is in the manual, but it does make complete sense. Then I purged it again for good measure, and now the system works as it should - all the radiators are getting warm except the ones I turned off. Those can be a project for another day, as can balancing the system. Just in time - this weekend the temperatures are meant to drop down to 18 degrees! Thanks, everyone, for your help.

mattmia2

Those radiators with the problem with the bleeders, you can probably purge them to get them circulating if you think about how to valve them off so they get most of the flow then the air elimination should take care of the rest.

My awesome is provisional because your piping is atrocious.