Installer has let new cast iron boiler condense for months.

john_james

Hi I'm looking for advice what to do, I've had a terrible experience with an installer my family has used for years. I'm not in the trade. I am in Ontario, Canada.

We recently had our boiler replaced with a Weil McLain CGi series 4. We use natural gas. We have a chimney liner. During the install I asked if he was going to install a thermostatic mixing valve on the return side. He said he was not. When he finished the install and turned the system on, condensate began leaking out the chimney. He said the water in the system just needed to warm up.

Condensate continued to leak out the chimney. I told him it was still leaking in late November. He came to look at it, but it wasn't fixed.

On December 14th I looked at the boiler temperature and it was set to the lowest setting. The boiler temperature on the digital screen said "106" (F). The supply side temperature gauge was likewise around 106F. The chimney was still leaking condensate. I asked him if I should turn the temperature up, since it needs to be above 130F to avoid condensation. He said he would be down to turn it up.


This was the vent duct on Dec 29th. These are brand new ducts they just installed.



He turned up the temperate but it was still leaking. On Jan 3 I texted him to let him know it was leaking less, but it was still leaking.

I texted him again on Jan 13 to say it was still leaking. I asked him if he needed a thermostatic mixing valve on the return side to keep temperatures above 130F, since our boiler only comes on about 6 hours a day (the Nest thermostat keeps track) and the water is cold when it does. When he was talking with a family member he said that mixing valves are for sinks.
I asked him what the return temperature is or how you can tell. He said he does not know. There is no return temperature gauge.

He thinks the exhaust duct between the boiler and the chimney is too large. Yesterday he told me he has the parts to replace it with a smaller one and will come in tomorrow. He says that should fix the problem. I texted him saying the manual requires a return temperature gauge on converted gravity or steam systems. (It also says it's required on systems with large volumes of water). He said the system was never steam or gravity. It sounds like he is not going to install a return temperature gauge.

Our 3 story building had a steam boiler installed in 1930. The old installation certificate is still in the basement. I believe the original pipes and cast iron radiators are still in use. There is 300-350ft of exposed 2" pipe in the basement, with plenty of smaller lines leading to radiators and upper floors. I estimate there is about 250L of water in the pipes in the basement alone.

250L is about 550lbs of water. The water is cold when the boiler comes on (basement cold) about 60F, warming it up to 130F with a 120k BTU boiler would take at least 550*(130-60)/120k*60~20 minutes. Even if the return was half mixed with 160F supply it would still be (100-60)/120k*60~10 minutes. This would mean the return temperature is below 130F for an extended period of time whenever the system comes on.


Sorry for the long post. This whole situation has been bothering me a lot. I have never had to deal with contractors before.

I am off base or does this boiler need some kind of protection? If so, what should I say to the installer?


PICS. Taken today



Gallons of condensate


The supply temperature still shows 125F after running for at least 10 minutes


Valve setup. Looks like its feeding supply back to return. I was pretty sure it's used to bring up the temperature on the return side. Installer said it's used for giving the pump pressure somewhere to go. I don't know what's right.


Old pipes. I'm curious what kind of pipes these are. There's about 300-350ft of these in the basement, plus many more smaller pipes.

mattmia2

Looks to me it was gravity hot water. It needs some sort of return temp protection scheme. Fixing that may not fix the venting issue but it needs to be fixed before the combustion can be addressed.

GGross

I am curious what @captainco has to say about your installers claim that the flue is too large!

My opinion is that the damage to the flue as it stands warrants replacing it at least. Personally I would just get a different contractor in there to do the work that needs to be done. The boiler seems like it needs return temperature protection, the current contractor doesn't want to listen and in the mean time you are damaging your new boiler. Cut ties with the contractor and get a different one.

Ironman

I don’t think that your installer knows the system very well.
 
With the volume of water there and installing a new boiler that has a much lower stack temperature, he’s created a problem that will eventually rot the chimney and boiler. The condensate is a byproduct of combustion and is acidic.

The red handle ball valve is a bypass that’s intended to be partially open to divert supply water back into the boiler so it can heat up quickly. Try throttling the valve partially open until you find a sweet spot between keeping the boiler warm and sending hot water to the system.

Set the aquastat to 165*.

mattmia2

I like how the mc is hanging from the old chains for the draft controls on the coal boiler.

Zman

You can tell what kind of contractor you are dealing with just by the mess they made of the sweat joints and the pipe dope.
I would recommend getting in touch with a qualified contractor to evaluate the need for bypass, either by managing the existing bypass valve or installing a mixer. The vent sizing and installation should also be on the list.

EdTheHeaterMan

john_james

Zman said:

You can tell what kind of contractor you are dealing with just by the mess they made of the sweat joints and the pipe dope.

The copper was done 20 years ago with the last boiler. The black pipe at the bottom was done recently. It was nearly all the same guys from 20 years ago. Edit: only one guy is the same

So the solder or pipe dope should be kept close the the joint? I should still see a bit of it but it should look tidy and not dripping or slathered over the pipe?

john_james

mattmia2 said:

I like how the mc is hanging from the old chains for the draft controls on the coal boiler.

There's an area on the opposite wall that's partially enclosed. I've heard that's were they dumped in the coal from above during street deliveries.

What does "mc" stand for?

john_james

I will let this contractor replace the flue.

After I will turn up the aqua stat and open up the ball valve.
Will doing this myself void any warranty?

Finally I'll find someone else to take a look at the system after and see if more protection is needed. Was my suggestion of a thermostatic mixing valve valid for this application?

Thank you all for commenting. This has been very helpful. Since this contractor kept brushing off my concerns I was worried I did not know what I was talking about (he has been doing this longer than I've been alive). Now I am confident he is the problem.

Ironman

“MC” = Metal Clad cable.

pecmsg

john_james said:

I will let this contractor replace the flue.

After I will turn up the aqua stat and open up the ball valve.
Will doing this myself void any warranty?

Finally I'll find someone else to take a look at the system after and see if more protection is needed. Was my suggestion of a thermostatic mixing valve valid for this application?

Thank you all for commenting. This has been very helpful. Since this contractor kept brushing off my concerns I was worried I did not know what I was talking about (he has been doing this longer than I've been alive). Now I am confident he is the problem.

It's your equipment and your money but personally he's had his chance and blew it.
We're not talking a simple mistake, bad judgement, having a bad day. He clearly doesn't understand and hasn't read the instructions and as such put you and yours in danger!

mattmia2

I hope you have a working carbon monoxide detector.

The vent issue could kill you.

john_james

pecmsg said:

It's your equipment and your money but personally he's had his chance and blew it.
We're not talking a simple mistake, bad judgement, having a bad day. He clearly doesn't understand and hasn't read the instructions and as such put you and yours in danger!

I am definitely getting another contractor in to fix the rest of the problems.

I was going to let him replace the flue pipe/duct going from the boiler to the chimney, since he is coming tomorrow. He wasn't going to charge me to replace the flue duct. Is even that a bad idea? I figure he can't mess up replacing a duct.

EBEBRATT-Ed

@john_james

I am suprised your getting any heat at all. Turn the aqustat up to 160 at least. If you open the ball valve wide (handle parallel with pipe) you will get no heat. If you close it you have no bypass and the return will stay cold.

Your going to have to find a sweet spot and it will take a few adjustments. Set the valve half way for starters and adjust it. try to set it so you get 20 degree difference between the water leaving the boiler and the return going in the boiler.


Your installer unfortunately is an idiot

But that will not fix this job. You need a thermostatic mixing valve or better yet a 3 way valve with a sensor on the return pipe going in the boiler. You have a lot of cold water coming back and it will destroy the boiler if left as is.

Your going to need a couple of thermometers you can tape or strap on the pipe to do this or buy an infared thermometer but put black electrical tape on the copper pipe to take a reading

john_james

mattmia2 said:

I hope you have a working carbon monoxide detector.

The vent issue could kill you.

Thank you for the warning. I have two detectors.

EBEBRATT-Ed

@john_james

Something like this will work and pretty cheap.

https://www.homedepot.com/p/General-Tools-Mini-Non-Contact-Laser-Infrared-Thermometer-Temperature-Gun-IRT205/303305337

pecmsg

john_james said:

mattmia2 said:

I hope you have a working carbon monoxide detector.

The vent issue could kill you.

Thank you for the warning. I have two detectors.

Low-Level?
UL listed detectors do not alarm until 70 PPM is reached and exceeded for up to 3 hours. At that point your hopefully going to the hospital.
Low Level alert at 15PPM

john_james

EBEBRATT-Ed said:

@john_james

I am suprised your getting any heat at all. Turn the aqustat up to 160 at least. If you open the ball valve wide (handle parallel with pipe) you will get no heat. If you close it you have no bypass and the return will stay cold.

Your going to have to find a sweet spot and it will take a few adjustments. Set the valve half way for starters and adjust it. try to set it so you get 20 degree difference between the water leaving the boiler and the return going in the boiler.


Your installer unfortunately is an idiot

But that will not fix this job. You need a thermostatic mixing valve or better yet a 3 way valve with a sensor on the return pipe going in the boiler. You have a lot of cold water coming back and it will destroy the boiler if left as is.

Your going to need a couple of thermometers you can tape or strap on the pipe to do this or buy an infared thermometer but put black electrical tape on the copper pipe to take a reading

I think everything is oversized in our system. Especially after I weatherstripped the historic windows over the past two years and insulated a 30sqft hole at the top of a stair well leading to the ventilated attic. When the boiler was set at 110F it was still heating the building during our Eastern Ontario Decembers, running for only 10 hours a day.

I also did a heat load calculation based on gas usage and degree heating days that gave me a building coefficient of 900Btu/hr/F. Using a dT of 62F gave me 57k Btu/h input (we have a 99%DB of 3.1F). In hindsight using a dT of 62F may have even been high, based on the fact our building has walls built from a foot of clay brick and seems to retain heat unreasonable well for being 160 years old. I suggested to the installer a 80k btu/h condensing boiler (upsizing by 140% from 57k), but he wanted to put a 120k but/h boiler. I did not have the ultimate decision. I am just a math geek in my 20s who read some of John Siegenthaler's hydronic heating book, so my family (and myself) decided to trust the installer who is licensed and has been doing HVAC longer than I've been alive. If anything this has given me more confidence in myself.

Thanks for the thermometer tip. This sounds like a good excuse to buy the Flir camera for my smart phone I've been looking at, but I might be reasonable and just use a thermometer.

john_james

pecmsg said:

john_james said:

mattmia2 said:

I hope you have a working carbon monoxide detector.

The vent issue could kill you.

Thank you for the warning. I have two detectors.

Low-Level?
UL listed detectors do not alarm until 70 PPM is reached and exceeded for up to 3 hours. At that point your hopefully going to the hospital.
Low Level alert at 15PPM

Thank you for making me aware of this. I just checked the alarm specs and it will display CO readings at 30ppm. It is currently showing 0ppm, so it must be under 30ppm. But the alarm does not sound until 70PPM is exceeded for 60-240 minutes. Wow. That's seems like it should be unacceptable.

The current sleeping spaces are separated from the boiler by two floors (basement -> 3rd) or a floor and 100 feet. I am assuming this is not a risk in the bedrooms, but still absolutely a concern nonetheless?

mattmia2

I'd use a strap on thermometer. Well i'd use the clamp on thermocouple that I have for my thermometer, but I have that mostly for refrigeration.

Modern Hydronic Heating knows more than whoever installed this boiler. The only reason you might go that large is to cover a domestic hot water load but that isn't a great decision with a cast iron boiler, it can be ok with a mod con.

pecmsg

and how often do you look at it?

john_james

EBEBRATT-Ed said:

@john_james

Something like this will work and pretty cheap.

https://www.homedepot.com/p/General-Tools-Mini-Non-Contact-Laser-Infrared-Thermometer-Temperature-Gun-IRT205/303305337

This would be good right?
https://www.homedepot.ca/product/ryobi-infrared-thermometer/1000837112

john_james

pecmsg said:

and how often do you look at it?

Good point. Probably not enough. I will try to be vigilant until it is fixed and inspected by a different licensed professional. The boiler never comes on during the nighttime setback, so that's not a concern until a really cold night, or I'll just turn it off at night.

The same installer is scheduled to come tomorrow to replace the flue duct/vent free of charge. I am thinking replacing the duct is a simple enough job that the original installer can't screw it up.

My plan is:
1. Let the original installer replace the flue vent.
2. Never use the original installer again.
3. After he is gone I will personally properly adjust the humidistat and open the ball valve.
4. Finally I will get another HVAC mechanic to come in and see about installing a thermostatic mixing valve or another protection device and check over the system.

Does this seem like a reasonable plan?

JUGHNE

How about a picture of the pump, standing over the top and looking down?

Just an idea of another possible problem, considering he is a hack.

john_james

mattmia2 said:

I'd use a strap on thermometer. Well i'd use the clamp on thermocouple that I have for my thermometer, but I have that mostly for refrigeration.

Modern Hydronic Heating knows more than whoever installed this boiler. The only reason you might go that large is to cover a domestic hot water load but that isn't a great decision with a cast iron boiler, it can be ok with a mod con.

There are electric water heaters, so there's no domestic hot water heating to explain such a large boiler.

john_james

JUGHNE said:

How about a picture of the pump, standing over the top and looking down?

Just an idea of another possible problem, considering he is a hack.

I'll get you one in a few hours. Thanks for being so thorough.

The pump on the old boiler was actually installed with the shaft facing vertically (red grundfos). That's when I became suspicious of these guys and started reading more about hydronics. The old pump ran continuously for 20 years though.

HVACNUT

JUGHNE said:

How about a picture of the pump, standing over the top and looking down? Just an idea of another possible problem, considering he is a hack.

Looks like a 007 that came with the package. Whether it's the right size or not, I don't believe we'll ever know. But then again, @john_james is a self described math geek so I challenge him to figure it out. Crack open those Seigenthaler books again.

There was mention of a chimney liner. What type? It's likely only the flue pipe (duct) needs to be replaced from the liner to the boiler, but if you're not on site, I'd ask for a pic of the chimney base, where horizontal goes vertical to see what condition that's in.
This is from a Series 3 manual but it's just as well. As sloppy as it is, the bypass is there, so use it. 

Out of curiosity, do you know the make and model of the old boiler? Wondering if the Nest will play with the new boiler as well as with the old. 
I have my own use for them. These are just some of several I've removed and replaced with something different. They're great for wrap-arounds.

john_james

JUGHNE said:

How about a picture of the pump, standing over the top and looking down?

Just an idea of another possible problem, considering he is a hack.

pecmsg

HVACNUT said:

JUGHNE said:

How about a picture of the pump, standing over the top and looking down? Just an idea of another possible problem, considering he is a hack.

Looks like a 007 that came with the package. Whether it's the right size or not, I don't believe we'll ever know. But then again, @john_james is a self described math geek so I challenge him to figure it out. Crack open those Seigenthaler books again.

There was mention of a chimney liner. What type? It's likely only the flue pipe (duct) needs to be replaced from the liner to the boiler, but if you're not on site, I'd ask for a pic of the chimney base, where horizontal goes vertical to see what condition that's in.
This is from a Series 3 manual but it's just as well. As sloppy as it is, the bypass is there, so use it. 

Out of curiosity, do you know the make and model of the old boiler? Wondering if the Nest will play with the new boiler as well as with the old. 
I have my own use for them. These are just some of several I've removed and replaced with something different. They're great for wrap-arounds.

They also are great for Skeet Shooting. 

JUGHNE

So yes, the pump is in the right direction, pumping into the return of the boiler.
Not the best location but not backwards.....this has happened more than one might think.

john_james

HVACNUT said:

JUGHNE said:

How about a picture of the pump, standing over the top and looking down?

Just an idea of another possible problem, considering he is a hack.

HVACNUT said:

Looks like a 007 that came with the package. Whether it's the right size or not, I don't believe we'll ever know. But then again, @john_james is a self described math geek so I challenge him to figure it out. Crack open those Seigenthaler books again.

There was mention of a chimney liner. What type? It's likely only the flue pipe (duct) needs to be replaced from the liner to the boiler, but if you're not on site, I'd ask for a pic of the chimney base, where horizontal goes vertical to see what condition that's in.
This is from a Series 3 manual but it's just as well. As sloppy as it is, the bypass is there, so use it. 

Out of curiosity, do you know the make and model of the old boiler? Wondering if the Nest will play with the new boiler as well as with the old. 
I have my own use for them. These are just some of several I've removed and replaced with something different. They're great for wrap-arounds.

It is the pump that came with the system.
I'll use the bypass valve until I can get someone in to install something better.

It was a slant fin. I think gg125. I did not use the nest on the old boiler. The old thermostat was a mercury filled Honeywell. We were using the Honeywell on the new boiler too before I installed the nest. In both cases the new boiler had condensation issues. It is the learning version. I don't have a common wire installed but that version of the nest uses a voltage divider to siphon power from the cold air handler (hot if there's no ac setup) without actually presenting a digital high/on signal. It should in theory work with any boiler, otherwise you can get a wall adapter for the common. At least that's my untested theory, sample size of 1.

I kept the Honeywell. Apparently people like mercury filled ones.

Haha nice pic. Is there a reason you keep replacing them?

hot_rod

i don't see an air purger? Or where the expansion tank tees in.

It will not matter where you set the temperature if the boiler the distribution mass is driving the boiler operating condition.

It needs a more appropriate return protection method

john_james

HVACNUT said:

JUGHNE said:

How about a picture of the pump, standing over the top and looking down?

Just an idea of another possible problem, considering he is a hack.

Looks like a 007 that came with the package. Whether it's the right size or not, I don't believe we'll ever know. But then again, @john_james is a self described math geek so I challenge him to figure it out. Crack open those Seigenthaler books again.

There was mention of a chimney liner. What type? It's likely only the flue pipe (duct) needs to be replaced from the liner to the boiler, but if you're not on site, I'd ask for a pic of the chimney base, where horizontal goes vertical to see what condition that's in.
This is from a Series 3 manual but it's just as well. As sloppy as it is, the bypass is there, so use it. 

Out of curiosity, do you know the make and model of the old boiler? Wondering if the Nest will play with the new boiler as well as with the old. 
I have my own use for them. These are just some of several I've removed and replaced with something different. They're great for wrap-arounds.









----------------------Nested block quotes don't seem to work-----------------------------


The pump came with the system.

The old boiler was a slant fin. I believe the model was gg125.

Both boilers used an old Honeywell mercury filled unit. The new boiler still had condensation problems with the old thermostat. I recently replaced it with a nest learning thermostat we got as a gift.

Without a common wire the nest learning model will siphon power from the cold control wires (Rc and Y1) by shorting them together using a voltage divider, so the air handler will see say 1V instead of a normal 0V off or 24V on signal. Since the boiler air handle is digital it won't turn on. It has a preference for shorting the cold side, meaning it won't short the hot side with a cooling device is present. In theory with some additional cooling appliance or a common wire the nest learning should work for any 2 wire boiler. My theory only has a sample size of one, so take of it what you will.

Haha nice pic. Why does everyone hate nest? I've gotten additional temperature sensors so I can select the middle temperature to control the boiler. It has been great so far, although I did have to turn off all the machine learning stuff and set my own schedule.

hot_rod

We've covered boiler protection in a few different Idronics. Here is one.
Siggy has covered it in 1/2 dozen articles for them last 30 years.

Yet the boiler installation manuals still show the "wishful thinking" boiler protection methods

Mad Dog_2

Why would you want that imposter back to do ANYTHING?  I always point out sloppy works especially shoddy soldering and tell the homeowner: " If he did this out in the open, what did he do in the walls?????"mad dog

exqheat

Indoor reset can adjust boiler temps to thermostat activity. This way in such a high volume system, higher circulation can heat at lower temps with very low difference between supply and return temperatures.

john_james

A few months ago I asked at the plumbing supply store who they would recommend for boilers, so I contacted him yesterday. He said to make sure the aqua stat was set to 140F and open up the bypass valve. He couldn't come until next week and that he would come install a thermostatic mixing valve, but it would likely be $500 (CAD) and I should just try the bypass first.

Since we have lows of -25C/-13F coming in the next few days I let the original guy come back to replace the vent. I figured carbon monoxide from the corroded vent was the immediate threat. Not using the boiler was also not an option. I wasn't there when he came. By the time I got back the new vent was leaking, of course.

I turned the system off for the night. This morning the water temperature was 60F in the basement pipes (I bought a digital thermometer like the one that was recommended.

I opened the bypass valve all the way and set the aqua stat to 155F.
After 4 hours the boiler's digital readout said 140F.
It started to leak condensate at the 3.5 or 4 hour mark. It definitely needs some boiler protection, so I'll make an appointment with the new guy.

I'll keep everyone posted. Thanks for all your help.

john_james

exqheat said:

Indoor reset can adjust boiler temps to thermostat activity. This way in such a high volume system, higher circulation can heat at lower temps with very low difference between supply and return temperatures.

Assuming the problem is low return temperatures, doesn't lowering the supply temperature exacerbate the problem?

Wouldn't more circulation cause issues when heating from a colder setback temperature, since the boiler output is fixed and there'd be more water and therefore less of a temperature increase?

mattmia2

john_james said:

Since we have lows of -25C/-13F coming in the next few days I let the original guy come back to replace the vent. I figured carbon monoxide from the corroded vent was the immediate threat. Not using the boiler was also not an option. I wasn't there when he came. By the time I got back the new vent was leaking, of course.

The issue, at least so far, isn't that the vent is perforated from corrosion (though that will happen eventually), the issue is that it may not be drafting properly, it may not be pulling the products of combustion up the vent but that they may be spilling out the draft hood.

john_james

@HVACNUT

That sounds like quite a challenge to figure out the correct pump size.
There is 8 or 9 different types of radiators and sizes (in both column and thin tube), not to mention the piping arrangement is hidden between the ceiling and floor. The pipes are uninsulated and would also act as major heat emitters. I may make a new post if I try to figure it out in the future.

Would having too large of a circulator exacerbate the problem of low return temperatures during a cold startup, when the bypass is fully open, but there's no other boiler protection like a thermostatic mixing valve?

I'm thinking it would since the boiler's output is divided between more water, meaning a lower increase in temperature and a lower supply temperature, which travels through the bypass, mixing with the return and this would mean a lower return temperature too.