2 questions

Nick_9

I have a 40000 BTU gas (natural) boiler (baseboard). They only sell 65000 BTU's now. Would that be a problem replacing a 40k with a 65k? Also, The expansion tank is in the supply line and the with new boiler, it attaches to the top of it. Can I have two expansion tanks on the system? Thanks. Nick

PJO_6

Sounds like...

you only went to a place that has a limited selection...for obvious reasons. That wouldn't be Home Depot/Lowe's would it? Maybe something via the internet?

There's a lot of smaller (than 65 kbtuh) gas-fired boiler available from the manufacturers...through a contractor. Don't do this yourself, unless you are VERY mechanically inclined - and at the very least get it started-up and combustion tested by a professional.

Just my $0.02...I am not a contractor.

As far as the expansion tank, others would give better advice...but why not cap one or the other? Put the circ. on the feed side after the expansion tank and you will prevent a lot of problems.

Take Care, PJO

Michal

call supply houses

you did not state if that 40000btu's is input, or net output, need to know that fact

Well if I were you I would go to a plumbing/heating supply and get quotes, there are many boilers in that reange for example the Weil Mclain gold CGi series 2 boiler rated at 50000 input and 42000 heating. But there are others that make similar such as burnham this is like what you want. You can do this yourself as long as you know what you are doing, there really is no burner setup on a natural gas units. As far as the expansion tank, should be located on the return or suction side of the pump, also there should one adequately sized tank, two are possible, but it seems someone just added another one, amtrol makes various sizes deppending on your house, you seem to have a small house/load so something like a amtrol 30 or 45 size expansion would do on that boiler. you can be a little larger on the tank, but not overkill, but too small will cause problems, if you need more info ask away

tommyoil

No burner set up on natural gas units????

I am under the impression that at the very least a combustion test be performed after the install. I could be wrong and it wouldnt be the first time. Just wondering.

Michal

natural gas vs oil

yes you would check draft, but the burners are already set up at the factory pretty much and set fixed, its not like on oil that you can change head pressure, over flame draft and stuff. I have never done a combution test on gas, on oil I have, now I might be wrong, but thats how I always understood it.

Unknown

Boilers are NOT adjusted at the factory

unless it says so in the manual.

Gas pressure must be, by code, checked at startup.

Limits must be set and checked for operation.

Combustion and CO must be checked on most burners, if there is a way to do so.

NONE of our equipment may be started without testing.

Noel

Steve_35

No, gas burners are not

> yes you would check draft, but the burners are

> already set up at the factory pretty much and set

> fixed, its not like on oil that you can change

> head pressure, over flame draft and stuff. I have

> never done a combution test on gas, on oil I

> have, now I might be wrong, but thats how I

> always understood it.

Steve_35

No, gas burners are not

"pretty much" set up by the factory. Just as a quick guess I'd say about 1/4 - 1/3 of all new gas or LP units we install require at a minimum a gas valve pressure adjustment.

tommyoil

The way I always understood it was....

If there is potential for a CO release then the equipment MUST be combustion tested (new or not). The fuel being used is of no consequense. Will the CO be any less deadly if it is produced by a gas burning appliance? The fact (as I understand it) is that final testing is the ONLY way to know that the combustion process is complete. I would consider it a huge gamble to start up and walk away from a boiler without being POSITIVE that I wasnt filling the house (someone elses house besides) with CO. Should I be doing things differently? I may need to be further educated on this subject (as I am certainly no expert) but that is how I always understood it to be. I think I would defer to a combustion test just in case the factory may have had an off day. Why take the chance? The factory is NOT the basement. Again, I may be over-reacting here or just plain wrong. My apologies if I am.

Unknown

Amen to that

this is just the problem in mis information about gas equipment not needing to be set up. That has never been the case. Equipment is more likely to have problems when new than any other time.

A technician needs a minimum of 100 hours of class room and lab training to even be ready to touch a gas boiler or furnace. Then after they have learned to light the pilot we will move on!!!

Empire_2

New Equipment

Some of the new equipment have inshot burners without a primary air adj. shutter. In fact I read an article on the option to increase manifold pressure, to increase BTU imput with little change in Combustion. Granted you cannot jack up pressure alot, but It's just a thought.