Replacing oil with gas - 8 contractors later

Atul

Very Fair point as no labor should be free. But it should go both ways. I believe in NJ there is regulation which is insisting on HVAC certification so that should allay the customer fears to some extent that they are getting trained service.

I also think that since there is a huge discrepancy in prices of labor for e.g., the average customer may be very hesitant to trust the person who is offering the service.

I dont know myself how to tackle this problem but I am all for paying for getting information that will help me make a decison..Else i will be penny wise , pound foolish...

For it to work, it has to be an industrywide standard fee.

my $.02

UniR_3

Oil to gas conversion

Have a 30 year + Smith oil boiler which I am converting to Gas.
House is old victorian (1895), two floors + finished attic + basement , 25*45 a floor.
Heating system is water based system.
Mix of Cast Iron Radiators + baseboards.
Looking for an indirect water system as well.

Sizing :
None of the contractors who came did a heat loss calculation. Only 2 of them, measured the radiators. One calculated (dunkirk boilers) that 150,000 would be adequate to heat + 60 gallon indirect water. The other calculated (Weil-Mclain) 250,000 + 40 gallon indirect tank.
The other contractors guesstimated it to be 150,000.
Question :
1. What are your thoughts on the sizing process ?
2. I was told the 40gallon indrect water heater would produce 400 gallons plus an hour, enough for a family of 6.

Brands & Type :
One of the contractors is a WM excluse but recommended against the mod/cons saying that with the cast iron radiators the efficiency will be much lower than the 93%. He said the ROI would not be worth it and that these boilers havent been proven and could be expensive to repair.
thoughts on this? I am open to brand suggestions but really need to find someone who knows what they are doing.

I am in the NJ area and need to find someone who knows what they are doing.

UniR_3

addendum on radiator/baseboard sizing

Roughly
72 sections (3 column + roughly 3 feet height)
36 sections of sun rack
50 linear feet of base board
25 feet of basement baseboard

heatboy_5

Are you expecting......

......someone to do a heat loss and design at no charge?

UniR_3

Are you expecting......

Not one of the contractors even mentioned this as an option. I did the SlateFin calculations myself but I would have expected a heating contractor to mention that this is a way to estimate the BTU requirements/crossmap them against the radiators and determine am I at the right sizing (if this is indeed the way to do it).
I did pay energy smart program to do a full house evaluation and I am very open to considering paying someone to do a heat loss calculation and recommend a product based on that and do the work.
What is dissappointing is that barring two contractors who did a radiator count (atleast some scientific approach), the others came up with numbers based on 'experience'.
If I have to spend the money, I would want to know that I am not oversized/undersized and see if a mod/con makes sense from an ROI perspective.

ALH_4

Have to ask...

Did you ask for a heat loss calculation? It may not be something they typically do, but they may still have the ability to do it if you want to pay for it. As a contractor, you begin to get a good feel for what typical houses in an area have for a heat loss. This experience can be relied on unless the structure has features that would make it differ significantly from the norm.

If you ask for a heat loss calculation and they refuse, that is one thing. If they simply do not offer to do a detailed heat loss calculation for everyone who calls them for an estimate, that is not necessarily negligence. Keep in mind this is an estimate not a design. Alternatively, you could hire a professional to design the system and let the contractor bid from those plans and specs.

Tom Hopkins

Have to ask...

To be honest - I didnt ask cause I didnt know at that time.

However, a good heating professional should have atleast mentioned this to myself and stated there is a charge.

None of the professionals were from that area (barring one) and this house is very unlike the others (seen 25+ houses in the neighbour hood) + this house was redone in 2001..heat loss on an hourly basis is 1 degree f per hour.

What concerns me is the disparity of the calculations 150k to 250k. Also didnt say the contractors were negligient but I am looking for someone who knows not only the how to install but the why to install bit.

Steamhead (in transit)

Keep looking

A heat-loss calculation is essential when replacing the boiler in a hot-water system. The amount of radiation is secondary- the output of a radiator varies with the water temperature. We've gotten jobs precisely because we did the heat-loss calculation and were able to propose a smaller boiler, which is less expensive to buy and operate. If a contractor won't do a heat-loss, don't even consider him. You know how easy it is to do a heat-loss on a computer, and laptops are inexpensive enough that no heating contractor has any excuse not to have one.

Just out of curiosity, what was the result of the heat-loss calc you did?

I'd also suggest, if you haven't done this already, that you first upgrade the insulation, windows and other things that will reduce your home's heat loss. Spend your money in ways that will save you money. If you do this first, you will probably find you can use an even smaller boiler. I once did a couple of "what-if" heat-loss calcs for a customer and we found that if he thoroughly insulated his house, we could install a boiler two sizes smaller than the original calc showed.

Whatever you do, avoid the old-style atmospheric gas boilers. These lose a lot of heat from the base, since the flames are completely below the cast-iron sections- just like a pan on the stove. A wet-base boiler with a power gas burner doesn't have this inefficiency (see below).

Mod-con boilers are promising, but some have had teething problems, and you have to have a good place to exhaust them as they cannot exhaust thru a standard chimney. The exhaust point should be a foot above the highest recorded snow accumulation in your area, otherwise a heavy snow can block the intake and exhaust and the boiler will either shut down or run unsafely. And there's no way a service truck will be able to reach your house thru that much snow!

Finally, why limit yourself to one fuel? Oil prices are up at the moment but you can bet gas utilities are jacking prices up too. Some boilers are approved to burn either oil or gas when the proper burner is installed and tuned. We use the Solaia line of boilers for this. These use a power gas burner that replaces the oil burner, and their wet-base design surrounds the flame almost completely with water-backed cast iron. This flexibility would let you burn whatever was cheapest per BTU.

If you haven't done so, try the Find a Professional page of this site- click on Resources at the top of the page, then Find a Professional to get there.

"Steamhead"

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Paul Pollets

Free advice

1. Mod-con boiler are ideal for most conversions. I've found the Viessmann Vitodens to be the most reliable, providing your contractor has been trained in their use and application. This boiler has been in production for over 10 years. Their committment to excellence is outstanding, and yes, they cost more than other products. There are over 45 wall-hung condensing boilers available in N. America. A consumer will have to dig deep to separate to glossy brochure from the real deal.

2. Install thermostatic radiator valves (TRV's)on all of the existing cast iron radiators

3. Make sure the copper fin tube baseboard is on its own zone, and not connected directly to any cast iron rads.

4. If you do go with a cast iron boiler, use a boiler outdoor reset control and a 4 way motorized mixing valve for boiler protection and precise tmpoerature setpoints.

5. Finding a competent contractor isn't easy. Wm Jannone & Sons does work in N. Jersey....and knows what to do.

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ALH_4

What I would do...

I would ask them how they arrived at the boiler size they did and ask them if they will perform (and provide a copy to you) a detailed heat loss calculation if they get the job. Ask them what software they use for this purpose. If there is anything you dont like about the explanation, avoid them. As you know, just because they have been doing things a certain way forever doesn't mean it's right.

I doubt they are asked for this information very often. You are the uncommonly well informed customer.

Steve Ebels_3

Personally

I would say flat out that anyone not recommending a modulating condensing boiler with fuel prices as they are should be, .........well......there's no family friendly way to put it here. A properly sized and installed m/c boiler will work very nicely with a cast iron system. The delusion that many in this field operate under is that radiators and baseboard don't provide any heat at water temperatures <180*. Nothing could be further from the truth. They still heat quite nicely but at a reduced output. That being the case, your heat loss and rad/baseboard sizing become critical to the success of your boiler update.

As far as brands go there are a fair amount of m/c boilers that are relatively new on the market. Obviously none of them have been around as long as the cast iron type. My own personal opinion is that there will be a fair number that fail at what a typical homeowner would term prematurely. They simply aren't going to last 50 years like the old behemoth currently in your basement. Then the question becomes, even if I have to replace it in 15 years, does it still provide a good return on my investment. Even a cursory glance at current fuel prices and worldwide stress in the oil market should answer that question. Painfully obvious would be an applicable term that comes to mind.

My personal favorites are the models incorporating a stainless steel heat exchanger, built in outdoor reset capability, provision on the control for indirect water heating and an intelligent control that can "learn" how your house heats. A Viessmann Vitodens would be at the top of that list followed by the Triangle Tube Prestige, then either a Munchkin or a Lochinvar Knight. All other things being equal, the service life of those brands will probably be in the order listed from my own experience.

The Viessmann stands alone as far as the control, the burner type and heat exchanger design are concerned. Nothing else like it that I know of. The Prestige has a very nice heat exchanger design also but not quite as robust as the Viessmann. The Munckin and Lochinvar are very similar in heat exchanger and burner design but have a few differences in the control package that will probably not be of major consideration to you. Those again are just my picks. Lot's of guys here have good things to say about the models with aluminum heat exchangers as well as other stainless brands besides those I mentioned. Your budget will likely determine what you use more than anything but I have to say it's probably more true in heating equipment than any other product that you get what you pay for.

In terms of service and maintenance the Viessmann is again well ahead of the pack. In fact, I have taught several of the homeowners we installed them for how to clean the HX on their own. Selectively of course but it really is that well engineered.

Back to your project........You mentioned that you did a heat loss. What is it? Have you calculated the output of your radiation also? If you can find the answer to those two questions you will be able to sort through most of the contractors that walk through your door. Armed with that knowledge you'll quickly be able to determine who's blowing smoke and who's not. If you can't do that or don't want to do that you may want to hire it done. Could be that the guy your hire to do it will also wind up with your work.

Bottom line, get educated, do your research into boiler types and keep on looking until you find the right one. You'll know when you're comfortable.

Tom Hopkins

Replacing oil with gas - 8 contractors later

Thank you for the detailed note. I will post my calculations tonight since its on my home computer and I want to be accurate.

the old-style atmospheric gas boilers : I would guess this means the chimney vented boilers? One of the contractors recommended the Weil-MClain CGA series as a better option than the mod/cons - ROI wise

that you first upgrade the insulation, windows and other things that will reduce your home's heat loss. : I was rushing in initially but had the energy smart folks do a review. I think I will contact them first to get the insulation into the walls etc etc ...I may do a before and after calc to see how this would look...food for thought..

Mod/Con boilers : I am currently talking to the building department here on codes. When I looked at the direct vent codes I saw no mention of a 10 foot distance from the vent and my property line. However the buidling code inspector is pointing me to a mechanical code (I still need to look this up) which says the direct vent needs to be 10 feet from the property line. Also, assuming I dont hit the 98% efficiency for the mod/cons, is the 93% an average number (Weil Mcalin ultra) that i would be hitting or does it go lower. If it goes lower, does it go lower for the 83% efficiceny boilers as well.

"Why limit yourself to one fuel?" - I am trying to move away from oil since - underground buried tank and a lot more insunace issues with this. I do get the logic behind using both if I could but from an operational effectiveness....though it may be a decison worth visiting.

Will look for professionals on the site..

Tom Hopkins

Re . Personally

Thank you for the detailed note. I will post my calculations tonight since its on my home computer and I want to be accurate.

"A Viessmann Vitodens would be at the top of that list followed by the Triangle Tube Prestige, then either a Munchkin or a Lochinvar Knight."
I havent looked at the Viessmann but will start looking into it. So far, all I have seen and read about are the WM Ultra's wherein folks mentioned high failure rates(comparitively speaking).

Mod/Con boilers : Also, assuming I dont hit the 98% efficiency for the mod/cons, is the 93% an average number (Weil Mcalin ultra) that i would be hitting or does it go lower. If it goes lower, does it go lower for the 83% efficiceny boilers as well.

I think the more I read sometimes, the more I know and the more confused I get...:) I do appreciate the feedback coming in.

Steamhead (in transit)

The W-M CGa

is an atmospheric boiler. Enough said.

When you're looking at Codes regarding mod-con intakes/exhausts, look for things like:

Clearance from windows or other wall penetrations- they may want as much as 4 feet.

Clearance above a publicly accessible walkway- they may want as much as 7 feet. What's "publicly accessible"? They may define it as anywhere that isn't fenced off.

Clearance above snow line- I already covered that. You'll want to go at least 1 foot above the highest recorded accumulation, as I mentioned earlier, even if Code doesn't specify this (yet). That falls under "best practices".

"Steamhead"

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Steve Ebels_3

Two things

There are two main factors that allow a m/c boiler blow a cast iron on/off boiler out of the water by far more than the difference in the rated AFUE.

The first is the ability to condense the flue gas and capture the latent heat normally lost up the chimney. This difference would probably correspond to the actual AFUE rating because the efficiency is calculated under steady state conditions and tightly controlled testing parameters. In short a good iron boiler will deliver 83-85% while a m/c boiler will deliver 90-95% under those test conditions. The least you will see from a m/c boiler under field conditions is probably around 85-88%.

The second and probably greater factor is the ability to modulate burner output based on a calculated target water temp. The burner on a standard type boiler has one firing position. Flat out whether you need all of it's power or not. Like driving your car with your foot to the floor or coasting, nothing in between. Here is where burner design and the onboard control come into play. The burner and control work together to establish the minimum amount of heat needed to maintain a selected water temp. You simply don't need 180* water in your system all the time. This morning for example, the outdoor temperature here was in the upper 30 to low 40* range and my boiler was running between 105 to 115*. Water temps like that will boost the efficiency past the AFUE rating along with the fact that the burner will be at minimum firing rate.

In real world applications many of the pro's here, including myself have seen actual energy savings of 30 to nearly 50% for customers that have switched.

SPB

I like the modcons also.

They work very well with cast iron. If you insulate like you say you most likely will end up with more radiation than you need. This is a good thing with with a modcon as you can lower the temps a create a lower return temp. This all adds up to more effiency. I Like the Prestige for replacements. It is a fire tube boiler as opposed to a water tube boiler. You WILL have iron floating around in your system water, from the boiler as well as the radiators. It is difficult to get all out. With the Prestige you can do a few things, to get the iron out so to speak. A dirt leg an the Spirovent or equivelent and even one under the boiler on the supply side, Use a valve so it can be blown down. Have had trouble with water tube boilers on change outs.
I just replaced a commercial cast iron boiler, 500,000 BTU with 2 modcons. The customer goes through so much propane that he had a meter installed. The 1st week he used 70% less than than he did the week before. The spring and falls were the worst. The old boiler would turn on for 5 seconds then turn off, turn back on in 2 minutes for 5 seconds. I have a happy customer. Good luck.

Atul

Replacing oil with gas - 8 contractors later

That help me understand the difference in layman speak as to say. Now I have to convince the building inspector of that

My heat loss calc 151,138 btu/hr for an outside temperature of 17f and inside of 72f. This is based on a living space of 7050 sq ft and includes an unfinished basement.
Without the basement, it is 120,000 btu/hr but since I am looking to heat the basement and finish it, I am counting it in the calculations.

On another note, sent emails to a couple of heating professionals from heatinghelp...

Atul

tim smith

Paul & Steve, regarding Viessmann ?

My take on the Vitodens is that I would agree the Vito 200 is the Mercedes of boilers even though I don't install it. I think the Vito 100 being a dumbed version to get costs down with out the Matrix burner and some other bells puts it down with alot of the pack. I then feel the Prestige stands above the Vito 100 based on equipt, quality and cost to this extent. Agree or not????

Paul Pollets

It's funny...

The Vito 100 does not have the Matrix burner, nor the Comfortrol OD. It has a simplified control meant to be attached to a thermostat and a DHWT. It still is made of 316TI stainless, the others, not. There's a huge difference between 316TI stainless and just 316. The Prestige is comparable, but the Viessmann is easier to install, having done both. Also, the TTDelta has a built in DHWTank for space savings when a small footprint is needed. The disadvantage of the Delta is it comes with a 100K burner. That's a little too much for most projects we work on. I look for 50-75K.








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Atul

Free advice

Thanks Paul.

I did call Wm Jannone & Sons but I am outside thier service area...I am in hudson county so if you or anyone knows of professionals who can help and/or experience with Viessmann Vitoden, would appreciate it.

I will also be discussing the feasibility of moving the baseboards into thier own zones since today its a mix and match..

The current thought is to keep baseboards in a zone and TRV's on the cast iron rads..

This has been a very helpful experience overall.

STEVE PAUL_3

OIL TO GAS CONVERSION

ATUL
Where in NJ are you located? We are in central NJ near New Brunswick. If you are nearby, call us, we can give you an evaluation.
Jack Dolan And Sons
732-247-2763

DanHolohan

Steve,

why not take an ad in Find a Professional? We can help each other.

tim smith

Paul, I knew you would not agree But

I am glad to hear your thoughts on it. Tim

Steve Ebels_3

Honestly.............

Between the Vito 100 and the Prestige I'd say each has their merits that would have to be weighed looking at the system on which either would be installed. The Vito 100 still has the radial HX and is much easier to service and clean than the TT. (front HX access instead of top) The Vito's HX is still 316TI as Paul said and until someone can tell me otherwise, I think that is the premier alloy in the industry.

The TT Prestige comes with more bells and whistles than the Vito 100. Reset and DHW capability mainly, but those would be factors I would take into account when the system warranted. Don't get me wrong, the TT is as good a piece of equipment as you'll find at that price point.

tim smith

Steve, I agree on the TI stainless

I wish the mfrs would just start using it and charge the nominal amount more. Just a better material for the job. Other merits to the TT is the low pressure drop through heatx and a bit of a buffer of water content. Just my shillings worth. Tim

Tom Hopkins

OIL TO GAS CONVERSION

I did call but my service area is outside. Thank you for the lead though.

Tom Hopkins

Replacing oil with gas - 8 contractors later

I havent found the Viessmann Vitodens specialist yet in my service area but I did find a lochinvar specialist.
The questions I have at this time are pertaining to the lochinvar and the water heaters.
I have been told that the indirect water heaters that come with lochinvars are not that good as their efficiency drops due to mineral buildups. Any thoughts on this?
Can I pair the Weil-Mclains indirects with the lochinvars or what would be better suited options?

The search continues but the heating specialist who showed up though this site, seemed far more knowledgeable than the others, spent the time to explain specifics, gave options. Keeping my fingers crossed.

Atul

Update

Thank you to everyone for thier insights...and here are my updates/woes

I had two professionals come to me from this site and one I called from a representative of boiler company

1. Professional x - Viessman - Heatinghelp reference - Very knowledgeable. Came in. Identified the current system as a gravity system converted. Spoke about options. Identified what he would do in the house. Presented options on approach. Did a full measurement of house for a future heatloss calculation, along with radiators..yay!! Said he would revert back to me in a weeks time with the cost based on options...yay!! Then nothing. I called, emailed but nothing back.

2. Professional y - Lochnivar - Heatinghelp reference -Very knowledgeable. Came in. Identified the current system as a gravity system converted. Spoke about options. Identified what he would do in the house. Presented options on approach. Some slight differences but not much from professional x. Didnt do a heat loss calculation but measured radiators. He reverted back with costs a full week delayed from when he said he would. I had some questions and wrote to him for a time to go over his proposal..its been a week and still waiting for that.

3. Professional z - Prestige - Called the local rep who had a heating expert call me - Expert came in with two others. Expert came in 90 mins late smelling of booze (strong smell). First thing he did was run a scare tactic on wife saying this is bad , that has to be done etc etc without even walking thru the house. Please note the heating help experts had seen the same thing but had spoken abt how it was not a big deal (width of inital 10 feet of the supply pipes which subsequnetly became smaller). Of the two that came in with him, they were installers but one of them was good. They traced all the pipes. They were surprised that I had studied some of what they were talking abt. I asked them to do a heat loss and they asked me if i wanted it done and that measuring radiators was good enuff. They left saying they would call me with the cost. No worries. I got a call from the 'expert' saying the number would be such and such. I said i was expecting around that but would need a full breakdown. No worries...didnt hear back since..

Now I do like both 1 and 2 even tgh 1 didnt call me back. Is it normal for heating professionals to be swamped that they cant service future clients or is this a sign of things to come?

Updates to follow as i get some..

bob young

free estimates

those free estimates are fast becoming a thing of the past. heat loss et al will be subject to a diagnostic fee to cover expenses ie: gas , travel time , research , layout piping diagrams -----all necessary to prepare a detailed true estimate. etc. possibly refundable on acceptance of signed contract. for nothing , that is what you usually get.....NOTHING.

Atul

Replacing oil with gas - 8 contractors later

Please see my earlier notes. I was more than happy to pay for the heat analysis.

However, this does not help me since the folks came, looked at the house and I would have expected a timely estimate since they took the time to come over.

the question I am asking is - is this a busy time of the year that the responses are so delayed or is this a sign of the service level to be expected?

bob young

touchy contractors

possible personality conflict. some contractors do not like customers who instruct them how to do their work.

Roland_15

Been there, got the T-shirt

I can sympathise with your plight. I had a similar experiance last year with an oil to gas conversion.

Yes, some of the heating contractors were uncomfortable(being polite) with me when I asked perfectly rational questions about the work to be performed. None of 'em offered to do a heatloss calculation and based thier recommendation solely on the size of boiler(way too big) already there.

I finally went with a contractor who didn't treat me like 6 year old and actually listened to my own preferences. The job was completed in three days and almost everything worked as planned. He did cut a few corners on the installation which had to be remedied later.

If I had to do it all again, I'd have done more research and I'd have been home to watch the install.

Mitch_6

We have been getting a tone

of oil to gas conversion requests. We send a standard E mail with basic price ranges and say we need to do a heat loss for accurate sizing. We say we must charge for the time to do this right.

Guess how many takers we get.

Mitch S.

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Atul

touchy contractors

Definitely considered that as one of the possibilities. But in this case, I am not an expert or close to it. I do understand the subject thanks to this forum and did ask questions.
I will add that professional x and professional y , really impressed me and they were consistent in their approach. We got along well since I did a lot of listening and they seemed happy to explain.
They also spent a lot of time when they could have left hence I could only conclude that they must be in serious demand (the other conclusion was I may not be able to afford them). My original question was - is this what I could expect in service or is this just how the seasonality works where the workload overtakes the estimation.

Atul

Been there, got the T-shirt

Thank you for the insight. Will keep that in mind. Glad you found a good match.

Any tips on what corners were cut so that we all could benefit.

Joey_2

You are Being a Pain...

These contractors see you as a pain. I'm not calling you names, but they don't want to work for you because you ask questions and know a little something.

Why work for a guy like you when I have 20 jobs lined up for customers who will take anything I give them?

Most contractors, except the few real professionals who will charge more than most people want to pay will run from a guy like you...

Roland_14

OIl to Gas

Hi Atul,
The heating contractor installed the exhaust vent too close to a window, faked wiring the low water cut-off,and didn't install an expansion tank on the indirect water heater per the manufacturers recommendation. He refused to come back and fix these problems so I got the local utility company to send someone else. It all worked out in the end.

I don't think you are being a pain by asking questions and educating yourself. You will be saving yourself headaches later on. Also, download and read all the information available on the equipment you will be installing.

Oh, and one more thing, if a heating contractor is worth his salt, he will be VERY busy. A good one is worth waiting for.

Atul

You are Being a Pain...

Agreed that is very possible.

The objective is to find someone who makes my winters warm but will keep long terms costs low. The objective is not simply to change my heating system if the same problems persists.

I always appreciate the folks here since they are taking the time to answer and educate. Not providing lip service, but both the top two contractors came from this site and left me impressed.

I will wait for them since I have a feeling they are swamped due to the demand and due to the fact that they have a lot of repeat customers.

But if I dont hear back, I may just video tape me with the next one, and ask for feedback on what I could have done differently

Atul

OIl to Gas

Thank you Roland.

Valuable tips. I will take the time to understand the product line.

And your last tip, definitely helps and keeps me patient.

bob young

the grief factor

It is called the grief factor. to work thru & deal with the nit-picking questioning of every little piece of pipe you install , a contractor must get compensated by charging a premium price or it just is not worth it. i have had these type set up a beach chair in the boiler room & stare a hole in my back for eight hour stretches. if the questions crack me , i either throw them out of their own boiler room or i vacate the premises.

Atul

the grief factor

Absolutely. What you are describing is a very hostile work environment and borderline harassment. No one should have to put up with that.

However, thats an extreme and does not apply in the case I am discussing. I think it is important to be an informed consumer.

I work in systems and I deal with a varied lot of consumers. There is a small % of people that are extreme and not pleasant to deal with. However, with the others : I prefer the ones that know what I am doing as they appreciate the complexity that goes in. I am also aware that some of them ask others for opinions and that no two experts have the same approach. However, I find the informed consumer to be easier in the long run since I dont have to keep running back if I do it right the first time around or if some minor work is needed.

A house is an extremely complex system made of complex sub systems. I have a very healthy appreciation of any of the experts who can make not only the sub-system optimal but also add to the optimality of the system.

In any case, I always like a confident professional who can explain the why and not the how. e.g. I want to know why a doctor wants to cut me up and not just how he wants to cut me up... extreme analogy but its imp to know the why for me...else I will probably end up being cut more than once