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Mod/Con Reliability

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Comments

  • Tinman
    Tinman Member Posts: 2,808
    Models change and with that some of the parts may change too. If I have 25 units of Model X installed, I'd carry a parts kit for X. Those replacement parts will likely be good for the lifetime of Model X boilers. If a specific component does gets upgraded or changed, I'd carry the new part and toss the outdated part. It's the cost of doing business in my opinion.

    If the manufacturer completely modifies Boiler X and it becomes Boiler Y. I get a new parts kits for Y. X Parts are still good for all the X boilers you still have out there. I think the key is to offer a very limited selection f mod con boilers. Find the manufacturer and boiler you're most comfortable with and stick with them.

    The only time this becomes an issue for the contractor is when a unit hasn't been manufactured for 15-20 years and they're being replaced with other models. Then, you're stuck with parts that will never be used. For me, it's been worth the investment. I sleep better at night knowing I did the best I could to provide good service. I also charged more than most in order to have those parts on hand.
    Steve Minnich
    D107NoelRobert O'Brien
  • NY_Rob
    NY_Rob Member Posts: 1,370
    I think it's a tricky situation where it comes to a complicated electronic component like a control or display board. Manufacturers only update the firmware when a bug (or several bugs) are identified and corrected. If you install a control board that's been sitting in your shop/truck for two years you may be installing a board that's several firmware revisions behind the current version. You may be doing your customer a disservice at that point by selling them a part that may introduce new problems they never had.

    Maybe just keep one "loaner" control board on hand- install it when needed then order the current version from the manufacturer. When it arrives (no need for $$$ overnight shipping) swap it for the loaner at the customers location when it's convenient. That way your customer never went without heat, you only have to stock one board and the customer will always get the latest revision firmware with all the bugfixes. Everybody wins!
  • JR3_Home_Performance
    JR3_Home_Performance Member Posts: 12
    From my perspective this isn't the right question to address 98% of the time. A well insulated home as well as retrofitted old homes will not get a payback on boiler replacement for natural gas. LP can be a different story but I'd rather see an investment into a heat pump if the existing system can be saved. If it's sold as a comfort upgrade as opposed to an efficiency upgrade then an outdoor reset can solve that with far less expense. If the home isn't well insulated then why not offer that service even if sub-contracted. I see larger profit margins in insulation jobs and less liability or call back risk compared to HVAC work.

    Running the numbers on my pre 1900 but moderately well insulated/retrofitted 3200 sqft duplex shows like an additional $200/year savings to upgrade to a mod-con on natural gas vs my retrofitted CI boiler. The few modifications I made to the 40 year old CI boiler has me running trouble free and at about an 80% equivalent AFUE. For those interested that is accomplished via an electronic pilot, flue damper, and custom de-rating and tune using a combustion analyzer. I have an outdoor reset but that really doesn't save much of any energy after you have a flue damper but that's a separate discussion. I also have an ECM circulator but that was just done instead of rebuilding the old circulator.

    If one really really needed to upgrade to a new gas boiler a good middle ground is the gv90+ series boilers that condense but don't modulate. With a proper amount of thermal mass/water in the system I test these boilers at 98% combustion efficiency. I believe the 92% afue ratings have to do with standby jacket losses (which may or may not matter depending on install location) or allowing the system to get up to 180F (of course you need a mod-con to be able to run at lower temps as well so there's really no difference there). The GV90+ can hit nearly the same efficiency levels as mod-cons with less complexity and minimal service requirements. All you really have to do is make sure the system is in tune and check the water chemistry once in a while.

    Better than going with a gas boiler....Heat pumps are the future so I'd rather see money spent towards say a Sanden CO2 heat pump water heater that is setup with a large reverse indirect buffer tank. That'll give you a combination of very efficient DHW and 15kbtu of heating capacity when DHW is satisfied. The cost per heat output with heat pumps is becoming more economical than even natural gas. Plus you can offset your own usage with PV. Have all this setup as hybrid system where a heat call just runs circulators to distribute the 120-140F water out of the reverse indirect. An outdoor reset can activate the old gas boiler as needed when system water temp drops below some threshold of 120F or so to make sure you also have endless DHW. With most homes (even here in upstate NY) you would achieve half or more of the home's heating via the Sanden heat pump setup in this configuration. Heck if you can get the back up gas boiler system yearly usage low enough it could make sense to switch to LP from Natural gas so as to avoid the monthly utility service connection fee (About $250/year for me)
  • Tinman
    Tinman Member Posts: 2,808
    It's not a matter of being the right question. It's just a different one than what you're posing. I don't think anyone would disagree that buttoning up the envelope is part and parcel to an efficient system. But modulating condensing boilers aren't going anywhere, anytime soon. They're here to stay. And with all due respect to Weil McLain, I'm going with a Viessmann or a Lochinvar long before I go with a GV90+. And without getting into specifics, the $ is very close.
    Steve Minnich
    Robert O'BrienGordy
  • Gordy
    Gordy Member Posts: 9,546
    With fuel prices at current levels buttoning up an envelope can have less payback than a High efficiency boiler. Especially when an existing dwelling is in question.

    Obviously doing both is double the pleasure.

    But to spend 30k to upgrade an envelope to reap an optimistic 300 dollars a year in fuel costs isn’t a good ROI.

    With insulation however it’s the gift that keeps on giving when done correctly. Not like a boiler, or furnace in which there is a definitive life cycle no matter how you go for efficiency.

    These are the things homeowners look at rather than the big picture of energy conservation. ROI on anything done to their castle.

    No one keys on fuel costs until they go through the roof. Usually it’s not long lived when they do, and then everyone backs off the HE train when fuel prices drop.

    This is where the EU, and other lands across the ponds have the advantage of sticking to efficiency standards, alternative energy, and methods with real enforcement, and benefit. They pay a lot for fuel, and have been for a long time. We in the states are gluttonous hogs because it’s cheap even when it’s high, it’s still cheap compared to other countries.

    We drag our feet when the opportunity arises. Take for instance the housing bubble. 80% of the homes built are no better in their envelopes efficiency than the prior 20 years. That was a severely missed opportunity to make a meaningful impact on conservation.

    The consumers expectations of products that last a lifetime has come to the realization that they don’t. As much as we would like them to. We have evolved into a throw away society sadly, and as the generations fade away that enjoyed the products that did last there is no going back, even though we could. Today’s business models don’t support that.

    @Stephen minnich has the right idea. Keep your line variety small, and stick to a brand(s) that get it right out of the box. Give the customer what they want in their comfort zone, and you as a service provider have done your do diligence in keeping the customer happy. From beginning to end.




    Tinman
  • Gordy
    Gordy Member Posts: 9,546
    By the way most people don’t think about local governments getting the same real estate tax income whether a new house is HE, or a Energy hog. They get their tax money by value of the home. The more energy codes raise the cost of a home it narrows the amount of people willing to build do to upfront cost. No home no tax income for the local government.

    Very few people see high value of anything in the walls, or above the ceilings. It’s the eye candy that sets the price point.
  • Steamhead
    Steamhead Member Posts: 16,796
    Gordy said:

    This is where the EU, and other lands across the ponds have the advantage of sticking to efficiency standards, alternative energy, and methods with real enforcement..........

    Some of the "enforcement methods" found in the EU would not fly here. For example, the German "chimney sweeps" can enter your home to test your boiler any time they want, and citizens legally cannot refuse entry. If the boiler fails the tests, and the owner doesn't get it fixed or replaced in a certain time frame, they come back and take it away. And in Germany, this is all perfectly legal. AFAIK there is no judicial review.

    This would flagrantly violate our Fourth Amendment, and rightly so.

    It's important to remember that the USA is one of the very few nations on Earth whose cultural and governmental history never revolved around blind, unquestioning obedience to a strong leader such as a king, queen, dictator etc. Such people might use unreasonable search & seizure as a method of control. Our Constitution was written and amended specifically to keep this from happening.

    I'm all for reducing energy use- that's one of our company's main reasons for being- but not at the expense of one of our country's founding principles.
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Consulting
    Solid_Fuel_ManRobert O'Brien
  • Gordy
    Gordy Member Posts: 9,546
    edited July 2018
    I’ll agree. It’s like that in Italy too. For a fee, yearly inspections are required. It’s a racquet as my uncle admits. Especially when they already know there is a HE boiler installed.......

    But, beside all the they are ahead of the curve compared to the states in their mind sets of conservation.

    Due to historical significance, A lot of the old structures can’t be touched to upgrade envelopes.
  • Solid_Fuel_Man
    Solid_Fuel_Man Member Posts: 2,646
    edited July 2018
    I still think it's a lack of real knowledge on the contractor's part. The small amount of residential I do is about 1/2 new construction or additions. Guys just don't take the time to do it right, or know how heat travels through an envelope. By rethinking some of the traditional practices thermal breaks can be pur almost everywhere in new construction.

    There are very few thermal bridges in my home which I built 10 years ago. And i saved a bunch of lumber too. House is naturally cool and dry in the summer and warm and 50% relative humidity in the winter. But I did the calculations and actually sized structural members according to load tables, instead of the typical "ah a 2x10 16" on center is what ya need there" mindset.

    But I'm not in Europe and don't want Europe to come here. Smarter investments shouldn't have to be legislated and forced into a people. If the neighbor wants to build a crap envelope house that's his prerogative as and as that is.

    Money saved, lumber saved, energy saved, and home that is structurally sound and quieter inside. Time spent though!
    Serving Northern Maine HVAC & Controls. I burn wood, it smells good!
  • Tim McElwain
    Tim McElwain Member Posts: 4,612
    I have been reading this posting with some interest and wanted to see what direction it would take. I plan to post some things when time permits.

    I think I may have some insight to offer due to my back ground and also my training. i was trained in electricity and electronics in the Navy and over the year have watched the changing electronic controls in particular as related to heating controls.

    I was at one time a consultant for 6 different control companies. My job was to sort of "kick the tires" and advise as to dependability based on my experience.

    One of the first Mod/Cons is an example: I was invited to take a look at a new Mod/Con which was still in the testing lab. I quickly found upon looking at the new product that it had a certain manufacturers electronic board on it. I knew the board was a problem as i had been doing some consulting and also working at times for them as a sub-contractor. I knew there was a component on the board they were using which had a reputation of failing after about 50 cycles. I advised the Mod/Con manufacturer about it and they chose to send it out for beta testing anyway. Sure enough they began to fail and the nightmare began. Interestingly they actually decided to look into using the board I had recommended and eventually changed over to that board and it was a success and then a later modification to that board was and still is a success.

    I will add more later time permitting. I do not plan to use any names here as that would not be wise.
    Robert O'Brienbob eckSolid_Fuel_Man
  • Solid_Fuel_Man
    Solid_Fuel_Man Member Posts: 2,646
    As an industrial control specialist, I see many electronics which run 200+ horsepower motors that's 250amps at 480 3 phase. Some of these drives and soft starters have been in service for a decade or more in very hot, extremely dusty, sometimes damp, with lots of vibration. Been working in a rock quarry recently. This stuff takes real abuses, it is expensive and well made. Electronics, for the most part, can be made to withstand many thousands of cycles and several decades of use... . If so desired.
    Serving Northern Maine HVAC & Controls. I burn wood, it smells good!
    NY_Rob
  • Tim McElwain
    Tim McElwain Member Posts: 4,612
    From the stand point of an OEM (Original Equipment Manufacture) they are looking for the least expensive yet functionally capable control system they can find.

    It is a fact that control boards (printed circuits) can be built fairly less expensive by assembly line construction. It is also faster to get the controls to market. I would hope that quality is not sacrificed for the sake of reaching some production numbers.

    It is also good to remember that on heating systems both FHW and FWA these control boards are used. Many of the components on the boards are similar yet not necessarily the most expensive or top of the line capacitors, resistors, relays, microprocessors etc are used. They basically meet the standard of the industry and have a typical expected life. It then comes down to the cycle rate of the equipment and many times these depends on the technician who sets the system up.

    That brings me to something that has been apparent to me for some time now. That is how well trained and capable are the techs who touch the equipment. Please do not take offense at what I am about to say but it has been my experience from training hundreds if not thousands of trades people that those who install boilers in particular are not well versed on electrical or electronic concepts. They often rely on others to handle those problems. It is my opinion that many installers need more training in this area in order to understand setup and later service these units. That in itself often create the "change the board" attitude because it is the one thing I do not understand.

    I have much more to say on this subject but will let this sink in first.
    NY_RobCanuckerSolid_Fuel_Man
  • Solid_Fuel_Man
    Solid_Fuel_Man Member Posts: 2,646
    "Rely on others".....I love it Tim!
    Serving Northern Maine HVAC & Controls. I burn wood, it smells good!
  • Steamhead
    Steamhead Member Posts: 16,796

    Please do not take offense at what I am about to say but it has been my experience from training hundreds if not thousands of trades people that those who install boilers in particular are not well versed on electrical or electronic concepts. They often rely on others to handle those problems.

    Not the case with our company- but you knew that.
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Consulting