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Slant Fin Boiler Good or Bad?

I'm looking to replace my 30+ year old boiler with a Slant Fin Bobcat 120. A 1,500 sq ft home with less than 100 ft of baseboard. I was advised I need at least an 60,000 BTU unit. Anyone have experience with this boiler. I read a lot of good about it but I'd like to hear from someone who has used or installed one.

Re: Slant Fin Boiler Good or Bad?

ok , first of all SlantFin is a good Amarican , US built company and back their products.
Now for the problem. I installed a bobcat 120 in june 08. It was constantly failing with code A01
I had to reset it. SlantFin replaced the electronics and then I had what can be described as "delayed Ignition" A loud band between ignition failures. The new control board did not require a reset because it was now auto reset. SlantFin then sent an engineer to my house. They recommended the exhaust be redesigned from a combo to individual plastic pipes.. two days later more delayed ignite issues.

Today the first day of heating, the fan that increases the gas flame temp started to sound like a fan rubbing on something with a clicking noise. So now I will be calling Monday to inform them of the new issue.
Now don’t misunderstand me. They have been very responsive. I have friends who have purchased WeilMclane, Burnam and others . All feel they made a mistake:( and even though I have some issues they are considering replacing with a SLantFin. The Bobcat is a very nice boiler and I’m sure will be a real money saver when I get it corrected. I have a affinity for problems. I asked for other slantfin customers and received a list from a distributor( SlantFin did not know about this ) and could not find anyone else who had issues so I guess I would recommend buying the Bobcat:)

I have the same size house as you.

2011 edit updateThis is a follow-up to the Bobcat I installed in 2008. I initially had some issues but they apparently all related to the igniter design. Slantfin engineers replaced the original design with one that allows the spark to as other suggested “not jump around” it has a much shorter length. Anyway the problems are non existent now and the boiler runs perfect ( hope I don’t jinx it). The Oil boiler I had used about 1000 gallons of oil a year. Ran during the summer for hot water. The cost was about $3100 in 2008. The Bobcat cost about $7500 to install complete with all new . The cost to run the Bobcat for hot water runs about $35 for a family of 4 a month. Heating runs about $180 during the winter keeping the thermostat at 70 during the day and 66 at night. So all in all I would say it was a good investment. :D

2014 update

2014 October update. All is good and the only thing I do is check the igniter and if needed replace. The total cost for the igniter is about $30.00 including the fiber seal. Other than playing around with the settings I do not have any issues (where’s the wood to knock on) Cost to run is very low compared to oil. My total cost to install was $7500.00 and with a cost for oil over 5 full years vs this unit I have it paid back in just over 3 years.

2015 update
the Bobcat B120 has been in for 7 years and is working good. No issues except to change the igniter about every 12 to 15 months.
the cost for heating oil was about $2000.00 per year not including hot domestic water on the original Oil boiler. the Bobcat runs both eating and hot water and summertime costs about $35.00 per month for hot water. Winter months generally from November to March run about $ 120.00 per month domestic hot water included.
So based on friends who have other heating units and have bills running twice as much I would say this is a good unit and would not hesitate to suggest it.
2016 edit

so far the Bobcat is running well and as stated before the only item needing maintenance is the igniter. I Replace it yearly at a cost of about $25.00 including gasket.
Currently researching maintenance contracts available from Slantfin. The local gas company at one time did maintenance for home units but the company was sold to a foreign Spanish company and they wont do any repairs and even closed their parts department. ( who let a US company be sold to a Spanish company)

Re: Slant Fin Boiler Good or Bad?


I was wondering if you wouldn't mind sharing your total cost for installation of the B-120. I've been shopping around for a condensing boiler to replace our 25yr old oil boiler, and the Bobcat is near the top of our list.

I'm hoping the problems you had were just a fluke, as I've also read many good things about the product. Did you also install an external storage tank? I know the unit holds 1 gallon, but I wasn't sure if that was enough to get instant dhw, or if you needed a secondary tank. Thanks for any info.

Re: Slant Fin Boiler Good or Bad?

I have had mine in operation for a week and there have been no issues. Knock on wood. I do not use a DHW tank with the unit. The only change I made was the compensation slope from the default 1.0 to 2.0. I thought the water was not hot enough with an outside temp of 46. I have the PVC vent and intake both running 36' up my chimney.

Re: Slant Fin Boiler Good or Bad?

:)I installed a Field Test model of the Bobcat about a couple of years ago before they came on the market. I too had the "A-1" ignition problem and an off reading with the outdoor sensor. Don't forget this was a test model. I got a new control module which took care of the sensor problem. There was also an ignitor problem which I think they have taken care of. My boiler has been running fine since then. Also have taken about 30% off my heating bill from the 20 year old boiler I had. I will be installing an indirect water tank when my gas water heater goes. That should also add some gas bill savings.

Just a note, If you go with an indirect, use the slant fin indirect, or a super store, and make sure you get the "sensor" for temperature control, not an aquastat control. Make sure you use a Taco 0011 pump for the indirect and use one inch piping.

I have used Slant Fin products since they bought out National Boilers. I'm talking since the 70's. Rarely ever had a problem. The best part is when I did have a problem, they were very responsive.

The best way to rate a company is to see how they respond to the worst scenerio. In this light Slant Fin Shines.

Re: Slant Fin Boiler Good or Bad?

On October 27,2008 I converted from a Weil Mclain Gold Series oil boiler to a natural gas Slant Fin BOBCAT 120. My home is 1980 square feet colonial. Much like the others i too had a situation with this system. That dreaded A 01 error left me in the cold. I did however call Slant Fin and they immediately resolved the situation sending me a updated ignitor(very easy to replace i didso myself). So far it is working better than what i expected . i would recommend the BOBCAT 120 to anyone looking for a new boiler. it is now fully functional with no errors to report. Im free to answer any questions regarding this system.

Re: Slant Fin Boiler Good or Bad?

I just installed the Bobcat B 120 this last fall and I have had only one issue. During a recent power outage, I started my gas powered generator. At first the Bobcat worked fine on the generator power, but after awhile it started switching the circulator pumps on and off in about 2 second intervals. I determined that my generator's output voltage tends to rise after it warms up and the Bobcat control board fails when the supply voltage is somewhere around 125 to 128 VAC. Everything else in my house (TV’s, computers etc.) works fine in that range. I called the company and was told that the board was "very sensitive" and they had no recommendations on how to deal with the problem. I have ordered an AC voltage regulator which should solve the problem. Other then that the boiler has functioned extremely well and my heating bills are noticeably lower.

Re: Slant Fin Boiler Good or Bad?

I would be interested in hearing from others who have a SlantFin Bobcat. I'm the 3rd control board and 4th igniter. It's been about 4 weeks and so far have not had any issues but thats not saying i'm free of problems. I had a Slantfin Engineer out to check and he admitted they have some issues with flame ignition.
The unit was installed last summer ( 08 ):confused:

See first post for update

Re: Slant Fin Boiler Good or Bad?

I must admit these posts are making me nervous but it has been installed since October and no problems. We have had a few below zero nights and I am extremely happy with the Bobcat.

Re: Slant Fin Boiler Good or Bad?

I was thinking of buying one with my refund check but I think I will wait. Hope everyone has their's working ok. Wait and see right now for me.

Re: Slant Fin Boiler Good or Bad?

Actually mine has been in since August not october. How expensive are the boards or igniters should I keep a spare around?


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