Heating Help

some irony

@ May 24, 2012 2:34 PM in Choosing an Indirect Hot Water Heater

Yes: some irony or exaggeration. I cannot imagine there is a good reason to put cyanides in an hydronic heating system, but I can easily imagine some cheapskate putting ethylene glycol in as antifreeze instead of propylene glycol. And ethylene glycol is kind-of toxic, though not as toxic as cyanides.

"Bacteria will not live in a non-o2 environment." Some will; some won't. Aerobic bacteria will thrive only in an environment containing oxygen. Anaerobic bacteria prefer an environment lacking oxygen. They should do very well in a typical hot water heater.

It seems to me that water could transfer from the boiler to the domestic water supply. When everything is working right, I agree that the 40 psi water in the domestic side of the tank would leak into the 15 psi water of the boiler and not the reverse.

But if the boiler is at 40 psi because the pressure relief valve is stuck shut from lack of maintenance, and there is a pinhole from the domestic into the boiler, then the boiler will be at 40 psi until the boiler fires. Then the boiler water will expand, exceeding the domestic side and water will flow from the boiler into the domestic water of the indirect hot water heater. True, this requires multiple failures, but unless you have a Murphy's Law Proof system, it is a possibility to be guarded against. I know the installation instructions for my boiler and indirect say that you must not have anything in the boiler that you are not willing to drink (not their exact words). They would not say that if there were no risk whatsoever.

What happens if the coil in an indirect fails?

@ May 24, 2012 7:51 AM in Choosing an Indirect Hot Water Heater

If there is only one failure, the higher pressure of the domestic water in the indirect heater will enter the boiler, and probably pop the pressure relief valve.

If the pressure reducing valve providing make up water to the boiler has also failed, allowing the boiler pressure to go up to the pressure relief valve setpoint, and that pressure relief valve has also failed shut, then it is possible for water to go from the boiler into the domestic supply. I am not a contractor, but I think it wise to assume that multiple failures can happen (Murphy's sixth law: if several things can go wrong, they will all go wrong, all at once), and that the boiler is filled with either potassium cyanide and water, or filled with some deadly bacteria that cause a slow painful death.

If forced make sure your fan is spinning in the proper direction!!!

@ May 21, 2012 9:05 AM in yellow flames, combustion problem?

We had that problem where I used to work. We had three very large main frame computers in the same computer room (the size of a small aircraft hanger). Two of them worked just fine, and one was flakey. They turned the A/C down to 65F and it did not help. This went on for months. Finally, someone noticed that the fans inside the computer were all spinning the wrong way.

I had a similar problem with a desktop computer. It worked fine in winter, but flakey in the summer. After I checked everything else, I found out the intake fan in front was blowing out. The exhaust fan at the back, and the one in the power supply at the back were blowing out too. So the fans were maintaining a partial vacuum inside the box, and not cooling very well.

Gotta check every fan, I guess.

easy make 120K a year sitting 8 hours a day at some lehman brothers office

@ May 21, 2012 6:43 AM in Review by "experts"

Sitting 8 hours a day at a Lehman Brothers office is probably a pretty lonely occupation these days. People who used to work there that are well-trained heating engineers and technicians might be glad to have their additional skills.

https://en.wikipedia.org/wiki/Lehman_Brothers

I had a landscaper who used to be an investment banker in NYC who got fired because the company he had worked at was over staffed, and they wanted to get rid of the higher paid upper level employees. He took up landscaping, for much less money. He said it was the best move he ever made. He could cut down on his drinking and smoking. Could sleep better. Quality of life improved. Unless you inherit a lot of money (best way to get rich), you can pay a very high price to attain financial riches. There are other forms of riches.

W-M heat loss vs. Slant/Fin program.

@ May 20, 2012 5:18 PM in heat load

I am a homeowner, not a contractor. But my contractor did not do a heat loss, and that offended me, so I did mine three different ways.

1.) I had an oil burner with a 1/2 gallon per hour nozzle and it always provided enough heat, so my first heat loss calculation was 70,000 BTU/hour maximum.

2.) Since I was getitng a W-M Ultra 3 to replace the oil burner with gas, I decided to calculate what I needed with the W-M worksheets. These:

http://www.weil-mclain.com/en/multimedia-library/pdf/weil-mclain-pdf/other-downloads/boiler_replacement_guide.pdf

When I was done it came up with 36,250 BTU/hour or 41,450 BTU/hour depending on the heat loss downwards from the radiant slab at grade or not. At the time I did not know if that is counted or not with a radiant slab. I am still not sure, but it did not matter.

3.) Then I found the Slant/Fin program and calculated it with that and got 29,234 BTU/hour. That confirmed to me that the smallest W-M Ultra 3 would be the one I got. The installing contractor said they recommended the larger boiler for a margin of safety. I have since figured out that he did not know anything about mod-cons even though he suggested using one.

So for my house, it shows how the methods compare.

Comments:

1.) After the fact, I could have known method 1 was oversized because the boiler would run 45 seconds, shut off on upper limit for 120 to 150 seconds, and repeat until the thermostat was satisfied. I know I found the rapid cycling annoying because I could hear the boiler run through the wall between my attached garage where the boiler was (and is), and inside the house. Made sleeping difficult.

2.) Method 2 turned out to be good enough because W-M do not make a small enough mod-con. It was enough that I thought about refusing the 105,000 BTU/hour recommended by the installing contractor.

3.) I think this is the most accurate of the three calculation methods. It wanted to know a lot more about the house, like the number and size of the windows, more choices as to the insulation, wall construction, cold and not so cold walls, etc.

My guess is that methods 2 & 3 are also a little too high as well. The cycling of the large radiant zone is acceptable, and the small baseboard is too fast, but much better now that I fiddled around with the controls (reset curve, upper limit on boiler firing rate when heating the baseboard zone, etc.). But basically, since it takes only 6500 BTU/hour when it is 0F and design temperature around here is 14F, there is not much that can be done. More baseboard might be good, so it could heat up the small zone faster (though it does not need to heat faster) and shut the zone off by the thermostat instead of the reset limit. That zone is the entire upstairs. Had I zoned each room separately up there, it would be an improvement to combine the zones.

Should I put snow melting in my driveway and make it part of the upstairs zone? Just kidding.

coil would not be adequate for hot water using gas.

@ May 19, 2012 1:36 PM in Gas Conversion

I am not a heating contractor, but I am prejudiced against coils anyway. I favor indirects mostly, and that is what I have.

But I do not understand why oil or gas would make any difference in the decision of whether you use a coil, an indirect, or a separate water heater. I mean other than price of the fuel, a BTU is a BTU and if you get enough of those per hour, it seems to me that a coil could heat hot water no matter how the water around it got hot enough and maintained it long enough, and the coil were big enough.
So these days, it seems to me that gas is a cheaper fuel to heat hot water (or an entire house), but who knows what the ratio between oil and gas will be next year? or the years after that?

Gennady reminded me of something.

@ May 17, 2012 9:26 AM in Cleaning water boiler system before installing condensing gas boiler

In the W-M installation manual, they recommend Rhomar for boiler water treatment products.

Soon after I got my Ultra 3 boiler, W-M came out with a recommendation to put Sentinel X-100 in it. They even supply it with each new boiler.

I have no idea what is in either of the two products (the stuff you leave in), but each seems to have a similar product.

They each also make a cleaning solution you put in, run for a while, and then remove.

If the new boiler has aluminum heat exchanger, ...

@ May 16, 2012 4:24 PM in Cleaning water boiler system before installing condensing gas boiler

... do not flush the system with trisodium phosphate (TSP) as you cannot get it all out and your heat exchanger will not like it. Weil-Mclain recommend you get in touch with Rhomar Water Management, Inc. You may wish to look here:

http://www.rhomarwater.com/products/residential-hydronic-radiant/

Where's the boiler pump for the boiler loop

@ May 16, 2012 12:26 PM in trouble with a new system

I think it is the black one to the left of the two PVC pipes.

But it does not appear to be piped exactly according the the I&M manual. The supply from the boiler shrinks down from the one-inch pipe from the boiler even though the boiler loop should be a minimum of one inch.

I just found the PRV in another picture. It seems to be in there sideways, and I think that is not code, but I am not a contractor and I could be wrong about that.

If the plumbing is somewhat like mine, The T that is on the return side of the closely spaced Ts is right above the black circulator. The supply side T is hidden behind the two white pipes. According to W-M. they should be no more than 12 inches apart. Mine are 1 1/4 inch, and they are 5 inches apart (4 pipe diameters).

It is easier to see on mine. (Installation by my former contractor.)

Short cycling?

@ May 15, 2012 1:44 AM in replacing heating distribution pipes with pex

If you have a lot of small zones, what will you do to prevent short cycling if only one zone calls for heat?

condensing boilers in copper fin tube application

@ May 14, 2012 12:35 PM in gas boilers, which would you pick?

I am a home owner with a mod con boiler. I have an indirect hot water heater, a large radiant slab at grade zone, and a small copper tube with aluminum fin baseboard (Slant/Fin 2000 series). Since I was getting a condensing boiler, I wanted to have enough radiation to ensure condensing so I had 14 feet of baseboard installed in each of the two rooms of that zone, replacing 3 feet of baseboard formerly there. The additional baseboard permitted me to run a maximum supply temperature of 135F instead of 180F. I have the smallest mod-con boiler in the Weil McLain product line, but it is too big to heat just the baseboard zone, so it does cycle too often, especially in the warmer part of the heating season. I have done several things to overcome this, short of adding a buffer tank and extra circulator.

1.) In my boiler, the home owner can reduce the maximum firing rate so that the temperature of the boiler rises more slowly, giving the controller time to notice that it is heating too fast and lower it on its own. Default maximum firing rate is 94% and I lowered it to 55%.

2.) I raised the minimum supply temperature from the 80F or so that I needed in warmer weather to 110F instead. This means the zone heats up faster than it otherwise would, but the heat from the boiler will leave the system quicker so the boiler does not bounce off the upper limit specified by the reset curve so fast.

I think the best solution would be to make that zone bigger, such as by taking another room off the radiant slab and adding it to the baseboard zone. Because of history and architecture, that is completely impractical. I do not have the money or the room for a buffer storage tank.

that opens up a whole 'nother can of worms.

@ May 13, 2012 12:51 AM in Treasurer-Condo Assoc

Do not forget one of Murphy's Laws: When you open a can of worms, to recan them takes a larger sized can.

installed correctly

@ May 12, 2012 3:28 PM in trouble with a new system

"Do you mean the zone valve does not open or the circulator for that zone does not run?  WE CHECKEC THE ZONE VALVE. IT IS OK."

Since you have two zones, are both zone valves OK?

"Do you mean there is no call for heat reaching one of the boiler's inputs? THE THERMOSTAT IS CALLING FOR HEAT."

Does the boiler know it? I.e., when the thermostat calls for heat, does the boiler fire and run using the correct reset curve?

"Is the U-control of the boiler set up correctly? I'M NOT SURE WHAT THAT IS."

The U-control is the circuit board in the top of the boiler that contains most of the electronics that runs the boiler and associated circulators. It listens to up to three thermostats (one of which is usually an indirect hot water heater). It must be programemd correctly and wired correctly for the boiler to work properly. It is all described in the installation manual.

"Do the zones actually work, but the boiler circulator is not running? THE ZONES WORK THE CIRCULATOR PUMP ALSO WORKS."

If that boiler is installed according to the manufacturer's installation manual, you will have at least two circulators. One in the primary loop, and one in the secondary loop. If you have two, you will have two zone valves. If you had no zone valves, you would have three circulators. And one more if you have an indirect fired hot water heater. So if you are trying to heat both zones, is the boiler circulator running as well as the system circulator? If the system circulator is not running , the hot water will come out of the supply pipe of the boiler, go through the closely spaced Ts, and return immediately to the boiler. In that case, the boiler will cycle pretty fast. Are the temperature sensors attached to the secondary loop fairly closely to the closely spaced Ts? Your system is piped primary-secondary, I hope. That is what Weil-McLain require.

Can you describe better?

@ May 12, 2012 12:58 PM in trouble with a new system

What do you mean by a zone shutting down?

Do you mean the thermostat for that zone stops calling for heat?
Do you mean the zone valve does not open or the circulator for that zone does not run?
Do you mean there is no call for heat reaching one of the boiler's inputs?
Do you mean that all the circulators and zone valves work properly, but the boiler puts out no heat?
Is the U-control of the boiler set up correctly?
Do the zones actually work, but the boiler circulator is not running?
Is the outdoor reset triggering the warm weather shutdown?
Is the reset curve wrong?
Was the boiler installed according to the manufacturer's instructions?

lways check with the manufacture before introducing chemicals of any type

@ May 12, 2012 11:33 AM in TSP and commissioning

That is for sure. My boiler manufacturer specifically warns not to use TSP in my boiler at any time, even if you flush it out immediately afterwards. I am sure they fear the cast aluminum heat exchanger would not be improved by the TSP.

I am just a homeowner.

@ May 12, 2012 7:51 AM in Using an indirect HW with smaller boiler

I have a mod-con and an indirect. Mine boiler happens to be the size recommended by the indirect manufacturer.

As far as I can tell, the only problem with too small a boiler is that the recovery rate will be less. For mine, they specify that I should set the boiler temperature to 190F when satisfying a call from the indirect. I have a 36 gallon indirect and a 80,000 BTU/hour (input) boiler. My hot water needs are small. I have actually reduced the boiler temperature to 170F when answering a call from the indirect and notice no lack of hot water. YMMV, of course.

Battery life???

@ May 12, 2012 7:35 AM in Carbon Monoxide: A Step Backwards

I got one of those CO detectors and it seems to work well. The green light blinks about once a minute. It always reads 0 PPM, but I do not have any gas appliances except my heating (and hot water) boiler, serviced every year, in the attached garage, so that is expected. If I push the Test Button, it does what the instruction sheet says  it should to.

It comes with a 9  volt battery, a Lithium one. In smoke detector service, these last 5 years or more. I think they are claimed to last 7 years and once I saw them advertized to last 10 years. They last a very long time in one of my photographic light meters, but that takes extremely little current. I realize the life depends on whatever the current draw is.

But in this CO Experts CO detector, the battery lasts only about 6 months. I just put the third battery in last night. Is this to be expected? Or is there something wrong with the CO detector? I am willing to replace the battery every 6 months if necessary, but if something is wrong, maybe I should do something about it. I wish it would last a year.

I have one of those cars.

@ May 12, 2012 7:23 AM in Beware of smart keys.

I have one of those cars. A Toyota Prius.

If I leave the car with the system ON with the key in my pocket, it beeps three times as I walk away from the car to notify me that the car is still ON. I do this only when I get home and leave the car to unlock my garage door. I find the three beeps a little annoying, but once I forgot in a parking lot, and really appreciated the reminder.

With a Prius, the problem is not as bad as with a conventional car because the gasoline engine does not run all the time. If you pull up to a stop light, for example, the engine typically shuts off. When it turns green, the car will pull away from the light and you can go a ways before the engine starts up again because the car runs off the high voltage battery. So the engine in my garage, if I left it on, would probably run only 30 seconds every few minutes (I do not know how often, since I never tried it; I can listen to the radio for 5 minutes and the engine does not run) to keep the battery charge up. Maybe even less than that. Still a bad idea, of course.

In deciding, do not forget this one.

@ May 11, 2012 8:30 PM in boiler feed on or off?

http://www.heatinghelp.com/article/183/Plumbing-Mechanical-articles/2180/Fill-Valves-Open-or-Closed-August-2011

Several new baseboards are about to be added.

@ May 11, 2012 7:32 AM in L8184E, 2 circulators, one T calls, high limit exceeded

If hot water does not flow through them, it will not help no matter how much baseboard is added.

I am a homeowner, not a professional.

@ May 8, 2012 11:07 AM in Old radiant system

My house had an old GE (1950) oil fired boiler with copper tubing in at grade concrete slab downstairs and fin-tube heat upstairs. All one zone, so all got the same temperature water. There was insufficient fin-tube upstairs.

From what I have learned, mostly at this site, a boiler like that should not be run at less than 140F to prevent condensation. And 140F is too much for the slab. Also, that boiler had no reset, so the temperature swings were intolerable. I reduced the aquastat settings so that the boiler ran between 130F and 140F, and that helped the temperature swings. Boiler was about twice the size it needed to be, so rapid cycling was the rule. It must have been a tough boiler because it did not rust out, though it ate vent pipes.

The way the water to the slab (and unfortunately to the baseboards) controlled its temperature was that there was a big loop that had the load (slab and baseboard) on the "left" side, and the circulator on the "right side. In the middle, across the loop was the boiler with a globe valve (later replaced by a ball valve). If that valve is closed, no heat is delivered to the system. Wide open delivers maximum heat, and in between is in between. There were no temperature gauges on it, so I do not know the actual temperatures delivered. I tested it by walking on my ceramic tile kitchen floor barefoot on a very cold day it it was uncomfortably too hot. I suppose a real temperature regulating valve would have been a better way. I have no idea if these were available in 1950, or if the builder knew to use one. I had the instruction book for the boiler and it did not say anything about adding such a valve, but it looked as though the boiler was meant to heat radiant slabs. The circulator was a big 3-piece one that finally died. The oil company who did my service at the time replaced it with a Taco 007 and it worked fine. I was surprised because it was so small compared to the original one.

Look at the pages starting with the one labelled Page 11 here. My pdf program calls it page 10. That is my original boiler.

http://www.heatinghelp.com/files/articles/1025/177.pdf

(Now I have two zones, each with its own reset curve, and outdoor reset. Much more comfortable and cheaper to run than before. Gas fired mod-con.)

Nearaly hypothetical question.

@ May 8, 2012 10:35 AM in gas gun on existing oil burner or new gas boiler

Venting below the snow line is surely a bad idea.
Around here, I am required (though there are other options) to have a vent about a foot down from the top of my boiler room, and a second one about a foot above floor level. The size of the vents depends on the BTU/hour rating of the boiler.

But since the floor is essentially at ground level, and the snow outside often gets five feet deep or more, what do contractors do if they want to do a safe installation and obey the code at the same time? Whoever built my house had the lower vent about 6 feet above the floor level (slightly higher than to the top of the boiler), and the higher vent about 5 feet down from the peak of the roof. No inspector seems to object to this.