Maintenance of New vs. Old

Jason_15

I just had the last annual service done on my Weil VHE circa 1983. It's humming away keeping me toasty as I write this, but I have already decided to replace it next summer. I have been thinking on getting a Munchkin, or Peerless Pinnacle. These are considered exotic where I live, we can't even get Veissman, Buderus, etc. around here. Most everybody has nat. gas scorched air. I have a baseboard system in an 1880's 2-story with tall ceilings. It must be somewhat insulated, as I only burned $1100 in gas all of last year, and that includes dryer and separate water heater. My thoughts have now shifted to a new CI boiler with OD reset. Probably a Utica or Burnham because that is what my preferred installer deals with. The thought of getting a condenser serviced around here frigtens me. I can just imagine sitting in the cold, cussing myself for getting something "exotic" that nobody arond here will service.

Constantin

Please educate me...

Recently, the recurring discussion of CI vs. condensing boilers came up. Leo G. made a number of very interesting points regarding the economy, longevity, dependability, and the ease of of maintenance of older boilers vs. condensing models.

For hot-water heat, could anyone comment on:

1. The fuel savings that retrofitting a OR-control system to a right-sized boiler entailed for the client? I've read Honeywell and Tekmar brochures claiming 9-24% annual fuel savings, IIRC, but what is the anecdotal evidence from the field?
   
2. Do you charge more for the annual maintenance of a modulating/condensing boiler vs. a standard CI unit? How do the annual maintenance jobs compare on a hourly basis?
   
3. Have you found the condensing units to be similar or worse in terms of dependability? Conventional wisdom would predict that the more complicated the unit, the more likely it will fail. Yet, many installers here have sworn by their Munchkins, Ultras, Vitodens', etc. as absolutely dependable. Anecdotally, is there a significant difference in the number of callbacks related to reliability between CI units vs. modulating/condensing boilers?

As always, your thoughts and insights are welcomed. Cheers!

S Ebels

MHO

"The fuel savings that retrofitting a OR-control system to a right-sized boiler entailed for the client? I've read Honeywell and Tekmar brochures claiming 9-24% annual fuel savings, IIRC, but what is the anecdotal evidence from the field? "

Retrofits for me are few and far between. About the only time we get called, it's due to the fact that it "don't work". We have however done some installs where a decent CI boiler was replaced with another CI boiler using a good control. In all those instances, the HO reported that fuel consumption was down 10-15% at a minimum. In the cases where we heard back that the savings were greater, ranging up to the high 20% area, there were also other circumstances such as poor piping or an oversized boiler that we corrected during the changeout. My take on ODR is an actual savings of 12-15% is almost a certainty along with better comfort.

"Do you charge more for the annual maintenance of a modulating/condensing boiler vs. a standard CI unit? How do the annual maintenance jobs compare on a hourly basis?"

Famous last words............. It depends. Scrubbing and brushing out a pin type boiler that's plugged full of baked on condensate or soot is no piece of cake. We usually wind up with one of those being about a 4 hour job. That's simply what it takes to do it right. Standard hourly rates apply and along with other charges for items used up on the job, can run as high as $300+. A more standard scenario would be maybe an hour to 1 1/2 hours for a normal clean and tune.

AFA condensers go, the labor involved in getting at the components to be cleaned varies a huge amount by manufacturer. I have personally cleaned and tuned a Vitodens in about 30-40 minutes. They are an absolute dream to work on. Unclip the covers, remove a half dozen fasteners and the whole burner/inducer is in your hand with the HX fully exposed. Another half dozen screws and the burner itself is fully dis-assembled. (Elapsed time, maybe 10 minutes, tops.) Can't say the same for other makes of Mod/Con boilers unfortunately. Ease and cost of service is often overlooked when considering purchase prices but here's an example of a good design saving an owner at least $50-$75 every year for the life of the boiler. That adds up. On the other hand, I have spent several hours on some other brands of Mod/Con equipment which will remain nameless at this point.

So to answer #2, We don't charge more per hour to service a high tech boiler. Many of them, with the exception of the Vitodens, do require more hours than a typical CI clean and tune, so yes, some of them cost more.

"Have you found the condensing units to be similar or worse in terms of dependability? Conventional wisdom would predict that the more complicated the unit, the more likely it will fail. Yet, many installers here have sworn by their Munchkins, Ultras, Vitodens', etc. as absolutely dependable. Anecdotally, is there a significant difference in the number of callbacks related to reliability between CI units vs. modulating/condensing boilers?

On average, the M/C boilers that I have run across require a little more upkeep than a typical standing pilot CI boiler. Add alectronic ignition in one form or another and the gap closes a tad. Add a vent damper and you're closer still in the number of service calls. The boiler block itself requires very little attention in a CI boiler as a rule. Most of the service calls are for external type equipment hung on the boiler. Again, most of my experience with M/C boilers has been with Viessmann's Vitodens and call backs/problems are very, very few so I'm not sure I'm a good overall reference. Even the Munchkin's that we have installed have been decent for the most part once you get them dialed in.

I have to say again that maintenance with a M/C boiler is more critical due to the fact that they run in a completely different "environment" than a CI boiler. Low temp and moist vs. hot and dry. If you let a M/C boiler go, you can expect to pay a bitter price. In other words, I don't think it will take long to burn through an aluminum HX found on a lot of the new M/C units. Likewise for the light gauge Stainless Steel variety. Pardon me for harping on the Vitodens but again, from what I can see, it's in a league by itself as far as long life.

In summary, I have to say that callbacks and service related issues are in the same range for CI vs M/C in my experience. Certainly no less and seldom many more in the case of any of the M/C's that we have installed. Markedly less with the Vitodens even considering that it's a relatively new product here.