I need a condensate trap!!

Timco

Inline, 3"pvc.



I have an Ultra 80 in service, heating a 3000sq' house with low temp. (floors)



Heats fine, but never leaves the condensing zone and it's a jungle in there! Just swapped the HX on warranty (rotted through) but now I would like to save the new HX from the same 8-year fate.



Got a SS inline 3", but it's for 3" OD.



Anyone?



Thanks, Tim

Jean-David Beyer

Can you be more clear?

I, too, have a W-M Ultra 3 80K BTU/hour unit. It already has a condensate trap at the bottom of the unit. It may be about one inch. And unless it is plugged up, it should not cause problems with the heat exchanger. It was installed in May 2009, so I have not had any problems with the heat exchanger.



I infer that you want to put a condensate trap in the vent pipe. Is that right? I am not sure why you want to do that. W-M want the vent pipe to be sloped back to the boiler, so I assume they want the condensate to come back and perhaps wash the heat exchanger a bit. If you trap it before it gets back to the boiler, this will not happen. Do you suppose that your exhaust is more acid that W-M expect, and this is what is dissolving your heat exchanger? I have mine serviced every year and I watch the technician, and after almost 5 years, the fire side of the heat exchanger does not seem to be dissolving away. The pins are still all there and seem to be the same size they were when new.



I assume that if the existing condensate trap gets plugged that the condensate would back up into the bottom of the heat exchanger ant that would dissolve it until it got so bad that the draft would fail.



P.S.: I notice that on my unit, there is a sort of ring around the area where the vent pipe connects to the boiler, so any water (condensate) that comes down from the vent pipe will be caught right where it connects to the boiler. This condensate goes down a small tube and into the condensate trap at the bottom of the boiler. So this should already do what you want done. If that drain tube from the top gets clogged, then you would have the condensate running down the vent pipe inside the boiler and entering the bottom of the heat exchanger. You can see this on page 41 of their installation manual, but it does not appear on the drawing on page 117. Perhaps they removed it from later boilers in this series.

Timco

clarify

So this boiler is under sized, and runs low temp. Add 25' of vertical vent with 4' at the top in a cold attic space, and you get constant condensing with near 100% of that running back through the HX. This HX I swapped had rotted out at the service opening and below the vent connection. WM said no problem based on pics, and swapped it with a new unit. No extension of warranty. WM redesigned the 150K+ boilers to have the trap and bypass but told me no such vent exists for the 80 or 110 because it was simply not needed. I have a unique situation where an inline trap would greatly increase the life of this boiler if all that condensate was not running back through the HX.

Jean-David Beyer

an inline trap would greatly increase the life of this boiler

I wonder what is unique about your situation, since I have probably the same boiler.

I have seen my heat exchanger after four years of continuous operation (indirect fired hot water heater) and no evidence of corrosion of the heat exchanger. (I see it every year at annual maintenance time.)



Does that mean that suddenly it will go in about 3 years? Would my natural gas have less acid by products than yours does? If this is common, is W-M having to replace lots of these heat exchangers? If under warranty that would then make them pretty expensive in the warranty line. If they do not replace them under warranty, that would make a lot of angry homeowners and installers. They still seem to be selling them.



One might think if this condensate running back into the bottom of the heat exchanger were really a general problem, they would suggest you tip the vent pipe the other way so the moisture that condenses there would go out the other end and make icicles outside the building. But is this condensate any worse than what comes out the bottom of the combustion chamber and runs down in to the condensate pump or drain? Because I would think that at least as bad, and an additional condensate trap before the vent enters the boiler could not catch that.



Some other boilers have a condensate trap in their vent outside the boiler.. I cannot remember which. But could you not find one of those and use it?

Timco

condensate

Each install is unique. What size venting do you have? How long? How many elbows? Piped P/S? What emitters do you have? What is your total load? What temp water do you send out? What is your average outdoor winter temp / lowest temps? It goes on and on....



In this case, boiler is undersized, and runs low temps, so it is always in that condense zone, runs more than typical because it's undersized and in a very cold area, and it's never above condensing temps unless it's a DHW call. LOTS of condensate. Yours may be getting above that regularly, or your vents are way shorter, or your house is smaller than 3200sq', or so on....



Do you believe condensate erodes or is harmful to aluminum? I do....



As for pitching away, it makes a HUGE ice tumor / hazard in the winter, and is irresponsible in my opinion. Deal with the condensate. That's as bad as guys I see that don't want to buy a neutralizer and just stub the discharge tube from the pump outside with the vent. In the winter it's a giant mess and in summer it kills all vegetation and leaves a lake.



Ahh, can't remember who? You sound like my rep! I need a 3" PVC inline trap. This boiler will last 100x's longer with a trap. I saw three WM HXs at the supply house when I dropped off this one, all rotted out from condensate, all warranty replace. They redesigned the 150K plus vents, but said there was no need for a redesigned vent for the 80 or 110, but replaced this one under warranty.



A 3" SS vent trap will not work. Needs to be PVC size. 

Jean-David Beyer

Each install is unique.

I agree that each install is unique. I was just trying to figure out what was unique about your system that caused the HX to dissolve away prematurely, because of the fear that your installation may not be that unique after all, and that my HX may be next.



"What size venting do you have?" 3-inch PVC.

"How long? How many elbows?"

Intake:    one 45 and one 90 elbow.; About 18 feet long.

Exhaust: two 45s and one 90 elbow; About 18 feet long.



"Piped P/S?" Yes. Near boiler piping is all 1 1/4 inch. W-M recommend at least 1 inch.



"What emitters do you have?" Radiant slab at grade downstairs (probably not insulated) and two rooms with 14 feet of baseboard in each.



"What is your total load?" About 30,000 BTU/hour when it is 0F outside. Design temperature around here is 14F.



"What temp water do

you send out?" 76F to 120F to radiant slab. 110F to 136F to baseboard.



"What is your average outdoor winter temp / lowest temps?

It goes on and on."

I do not know the average outdoor winter temperature. A wild guess would be in the upper 20s. Right now it is about 32F, It was down to 19.8F once so far this heating season. The coldest I remember it getting was about 9F....



"In this case, boiler is undersized, and runs low temps, so it is always

in that condense zone, runs more than typical because it's undersized

and in a very cold area, and it's never above condensing temps unless

it's a DHW call. LOTS of condensate. Yours may be getting above that

regularly, or your vents are way shorter, or your house is smaller than

3200sq', or so on...."



Well mine is about double the size it needs to be. But they do not make a 40k or 50k, and it runs low temperatures too, so it is always in condensing mode except for DHW. I tried measuring the condensate, but my measurement is N.G. I put a pail under the condensate outlet and it overfills the bucket in 24 hours on days when it runs a lot. I need a bigger bucket or to check it more often, but a bigger bucket, even if I had one, would not fit. I estimate it is a 2 1/2 gallon bucket.



My house is 1150 square feet (cape cod type, with excellent windows, good insulation, not so good infiltration when it is very windy).



"Do you believe condensate erodes or is harmful to aluminum? I do...."

Sure: so do I. I know it depends on the alloy, but none are as tough as the right stainless steel alloy. I just assumed that they made the casting at the bottom thicker so that even including the attack from the condensate, it would last long enough. And they may have anodized it as well (not colored, though). Unless they goofed and some of it gets trapped in there where the drain is and I cannot see it. But in the main body of the HX, there seems to be no corrosion. I just assumed that W-M who have been in the boiler business a long time would have considered that and designed so this would not be a problem. I could be wrong of course. Aluminum is a tricky material. If exposed to acids, it has a problem. If exposed to bases it has a problem. Where I used to work, we were doing a slight cleaning of sheet aluminum (probably .0.050 inch or so) in a sodium hydroxide solution and the technician forgot and left it in overnight. Shim stock in the morning. It seems to last OK on aircraft wings (though it may well be more conentrated in condensate), and I bet that HX is a lot thicker than an airplane wing. I should measure the pH of that condensate. It is mainly carbonic acid that is not very strong.



"As for pitching away, it makes a HUGE ice tumor / hazard in the winter, and is irresponsible in my opinion."

Well, of course. I was not seriously advocating that. If I wanted to do it, I would certainly pitch it down pretty severely so that the water would rush out and not collect and get frozen. And do it where the ice build-up on the ground would not be a problem. As it is, I do sometimes get small icicles as the stuff condenses a little on very cold days.

Ironman

A Trap?

Why a trap? You don't want to trap a vent, that would block the flow of exhaust gasses. All you need is a 3" PVC Tee and a 3 x 1/2" bushing to go in the tee to drain it. Then trap the 1/2" drain line out of it. Buderus includes one with their GB142 boiler, but you can get the fittings at any plumbing supply.

Timco

Trap

Not a P trap, an inline vertical trap that has a catch groove or trough all the way around that catches condensate running down the pipe wall. No loss of pipe diameter or flow.

Jean-David Beyer

an inline vertical trap that has a catch groove or trough all the way around that catches condensate running down the pipe wall.

I wonder how to make one. Since Timco and I seem to have similar installation, with some vertical as well as horizontal vent pipe, and IIRC we both have 3-inch PVC,. I wonder about making one with two 3-inch to 4-inch adapters, a piece of 4-inch PVC and a short piece of 3-inch. Glue the 3-inch into the bottom (inside the adapter) and so on. Then drill a large enough hole so the water trapped can be drained (continuously), and run that with suitable clear tubing to where it needs to go. In my case, I suppose I could drain it into my condensate pump reservoir if I kept the end under the minimum water level in the condensate reservoir. If Timco does not need a condensate pump, he could figure out something. I suggest clear tubing so if the unit gets clogged up, it would be noticed and could be cleaned.



I should think a little more about this before trying to build it.

Ironman

The Tee

Using the Tee with the bushing I spoke of will work for vertical or horizontal depending upon whether you place the bushing in the bull of theTee for a horizontal line or the run of the Tee for a vertical line. In the case of a vertical line, the Tee would cause a 90* turn of the 3" line just like an Ell. Then the bushing would be on the bottom for drainage.



You wanna place the Tee as close to the boiler as reasonably possible.

SWEI

Low heel inlet 90º?

I know they make 3" x 3" x 1-1/2"

Steamfitter66

I don't understand the problem

Most of the condensing products are designed to condense continually. A secondary in a furnace never dries out. A secondary in a tankless same thing. 90% of what I have installed condenses all the time at 70* return temps.

You have another problem like inversion of exhaust or not set correctly.

What are the analyzer readings?