Buderus GB142 no heat *update* error codes

MaxMercy

A co-worker of my wife just called me because he has a Buderus GB142 that quit a week ago. His house was built in 1983 and he had the Buderus installed in 2010. He had three companies look at it, and only one tech seemed to really understand the unit. Unfortunately, all three companies recommended total replacement. FWIW, the symptoms include recent puking of water, low pressure and then high pressure. One of the techs seemed to think it might have a bad expansion tank (my thought) but also that some sensor or board was bad ("temp on one side didn't match the other side"), parts not available for several weeks, expensive, and no guarantee it would work.

I don't know anything about these modern units so I called a buddy who might be able to help him. While I'm waiting for the return call, my question to the group is whether the high efficiency of these offset their (apparent) short life and cost of repairs when things do go wrong.

My three year old Slant boiler is maybe 86%,, a consenser maybe 98% at best. If one burns $1K in fuel a year, would saving $150 ever pay for itself if the boiler has to be replaced in 15 years or needs expensive parts?

mattmia2

i mean a thermometer and ohmmeter will sort out the temp thing. My bet would be on a pump or 3 way valve, maybe a strainer.

MaxMercy

I wouldn't know where to check. I've never even seen one of these in person. Do these produce error codes?

What is a typical lifespan of a boiler like this?

mattmia2

I know nothing specific about that model, I'm just speaking in general terms about control systems.

GW

It’s a little odd your heating guys are saying, “it might be the expansion tank”. That’s one of the more basic fixes for heating guys.

If you have a high temperature system like most people have, the Buderus GB 142 certainly is not running at 95%. High 80s or low 90s at best

Big Ed_4

It is best to have experience tech with the proper tools sit in front of the unit and walk through with Buderus tech support and find the actual problem . A experience tech would have a analyzer , Mano meter and a proper multi meter ..

The expansion issue is more of a system issue and should by now been corrected by an compantant tech .


It will cost more to guess , then to diagnose

MaxMercy

GW said:

It’s a little odd your heating guys are saying, “it might be the expansion tank”. That’s one of the more basic fixes for heating guys.

If this was a standard pin boiler, I would have sorted it out for him, but then, any of the three guys he called to repair his problem would have done the same. He called three techs and they all told him his 10 year old Buderus needs replacing.

GW said:

If you have a high temperature system like most people have, the Buderus GB 142 certainly is not running at 95%. High 80s or low 90s at best

Which makes me wonder what advantage there is to a complicated and expensive system like a mod/con if not halving the cost of fuel at least. A quality three pass or pin boiler will last 30 years minimum, and most parts are available at big box stores. My original builder spec steel vertical tube boiler ran 28 years and I only replaced it because it gave me 30 years of good service and I thought it was on bonus time.

MaxMercy

Big Ed_4 said:

It is best to have experience tech with the proper tools sit in front of the unit and walk through with Buderus tech support and find the actual problem .

He did say one of the three techs was on the phone with Buderus. I wasn't privy to the conversation so I don't know if Buderus suggested something that might have fixed it. The end result is that three technicians condemned an expensive 10 year old boiler because it won't run for reasons other than a catastrophic leak of some sort.

So getting back to my original question and rephrasing it a bit, would my wife's friend be better off going back to a good three pass or pin boiler and give up maybe 3-5% efficiency for a lot lower cost and double or triple the life of the equipment???

Thanks for any insight.

Ironman

Have you looked at the complexity of the newest cast iron boilers? There's as much stuff to fail as with a mod/con. And we're seeing far more repairs on the 80%+ cast iron than the mod/cons.

A couple of things that are almost always over-looked in this discussion:
1. A new cast iron boiler will almost always require that the masonary chimney to which the old one was connected be re-lined. Obviously the mod/con can be vented with some form of approved plastic pipe.
2. The AFUE rating of a mod/con does not include the savings that the ODR function can provide. Even with high temp fin tube radiation, a mod/con can operate at 140* or below a substantial part of the heating season. That can easily account for another 15%+ in fuel savings that's not in the AFUE rating.

Obviously, the block of a cast iron boiler should outlast the HX of most mod/cons, but with the complexity of controls on either, and the severe lack of qualified service tech's in this industry, it's always gonna be hard to find competent service.

The three "tech's" that said the GB 142 needed replacing obviously did so because they could fix the the problem and wanted instead to make a sale. To evaluate mod/cons vs your 28 year old boiler solely from this scenario is not fair or accurate.

MaxMercy

Ironman said:

Have you looked at the complexity of the newest cast iron boilers? There's as much stuff to fail as with a mod/con. And we're seeing far more repairs on the 80%+ cast iron than the mod/cons.

I replaced my old builder spec boiler with a Slant Fin TR-30, which is a very simple device. It has a Beckett AFG, Hydrostat 3250+, and a Beckett 7505 control. All these items are easily and inexpensively serviced or can be replaced the same day if any fail. I expect the Slant to last 30 years, and more importantly, is still being made.

Ironman said:

1. A new cast iron boiler will almost always require that the masonary chimney to which the old one was connected be re-lined. Obviously the mod/con can be vented with some form of approved plastic pipe.

Understood. I know the flue temp of the Slant is about 275F less than my old tube boiler, but the flue liner isn't all that expensive compared to the scope of replacing the boiler.

Ironman said:

2. The AFUE rating of a mod/con does not include the savings that the ODR function can provide. Even with high temp fin tube radiation, a mod/con can operate at 140* or below a substantial part of the heating season. That can easily account for another 15%+ in fuel savings that's not in the AFUE rating.

I didn't know that, which is why I asked. 15% drop in heating cost is not insignificant, although it doesn't seem to cover the cost of the shorter life of a mod/con compared to an old school boiler. Still, the Hydrostat I have on my Slant Fin allows for ODR, which I can't use right now because I (stupidly) am using the coil for DHW, which I will address this spring by adding an indirect. The Slant TR-30/Hydro 3250 combo also allows for cold starting - something I can't set it for with the DHW situation I have now. Would the use of ODR on my Slant provide similar savings that the ODR does for a mod/con to close the real world fuel usage?

Ironman said:

The three "tech's" that said the GB 142 needed replacing obviously did so because they could fix the the problem and wanted instead to make a sale. To evaluate mod/cons vs your 28 year old boiler solely from this scenario is not fair or accurate.

Understood, but the end result as far as my wife's friend is the same: he's got a 10 year old boiler that can't or won't be fixed locally. If he had an old school boiler I would have fixed it for him. Since it's not leaking water or combustion gasses, it seems to me this Buderus can be fixed, but he's already paid for three technicians to check it. At this point he's aggravated and is inclined to just chuck the whole system and start again.

Thanks for the info.

Jamie Hall

Some interesting points here...

On the pressure changes and the relief valve burping. That's a system problem, not a boiler problem, and whoever suggested that the expansion tank needs attention is probably right. Don't blame the Buderus for that.

On longevity.

One has to distinguish between the boiler itself -- the mechanical collection of parts which converts fuel into heat and then into hot water -- from the controls. The newer boilers do have a shorter life than the older ones, simply because in the search for efficiency they are more highly stressed, both thermally and physically. The manufacturers have a vexed tradeoff between longevity, cost, and efficiency. You can have two of the three -- but never all three.

Then there are the controls. I would not expect an electronic computer based control to work for more than 10 years in the field, unless it was very expensive. But -- this is true, and apparently acceptable to the public, as it is just as true of kitchen appliances or fancy TV sets or games or automobiles as it is of heating systems. The problem becomes that first, it is usually less expensive to replace the offending bit of electronics and often everything that is attached to it than it is to repair it, second, they are almost always proprietary and parts may be very difficult to get, and third, they are unique to a system -- so a technician, for instance, may be a whiz at brand A and completely at sea for brand B. People accept this for automobiles, why not boilers?

None of which helps your friend, I realise -- except the pressure issue. That, as I say, is not the boiler, and any competent tech. should be able to fix that in a few hours.

Ironman

@MaxMercy
It appears that you’re comparing your oil burner to a gas mod/con.

Again, an apples to oranges comparison which to me is not objective. I have a Ram Dually with a Cummins diesel, my wife has a Honda CRV. Comparing one with the other would be the equivalent of what you’re doing.

MaxMercy

I talked to my wife's friend a little while ago and asked if there were any trouble codes. He said he was told there was a 2F and a 271. I found the service manual on line and it mentions a temperature difference between supply and safety sensors is more than 27F.

Ironman

That would indicate a lack of flow. Air bound, bad circulator?

There's no reason even an average tech couldn't diagnose and fix that.

mattmia2

And whatever you do, do not let any of those people replace the boiler, an installation by any of those people will only make things much worse.

Big Ed_4

I would just repair with what you have .. Besides the expansion issue which may need a new tank . What is needed to fix the boiler ?

mattmia2

It is possible the issue with the relief valve is overheating from the lack of circulation.