gravity system boiler replacement

[Deleted User]

Dose any one have any pics of jobs that they have done? I do maby five a year. Ive taking some pics but my camara needs a lot of light it really only works out side. Any way my company sells Weil-Mclain and I use the 1/2 inch tapping for the extrol tank and feader. The circ and lowco sit on the supply nipple followed after by a bypass valve to the return. It looks great every time but I want to make sure im not missing somthing befor I make this standard replacement for gravity systems.

bigugh_4

pudding ?

Sounds good! must look good to you and that is ok. but the proof is "Does it work" Are Folks warm and with even comfortable heat?
Go back to those jobs and obtain their feedback. Fuel bills, Drafts, eveness, overall feeling from the folks. That will make the difference in how your "Pudding" skills cook! bigugh

Boilerpro_3

Some additions to above

Most gravity conversions achieve quality comfort and low fuel usage, however, my big additional concern is with equipment and efficiency longevity. I never have liked by passes on these sysemm because the boiler still takes fowever to warm up. These sytems are especially variable,with huge differences in operating temperatures throughout the heating season. They run in the mid 80F supply in warm weather and then 130 in typical weather and then maybe 180F in real cold snaps. Fixed bypass piping can not possibly deal well with these huge variations and still provide boiler temp protection. The only time I use a bypass is on older boilers that I am repiping for other reasons and am trying to at least improve the temps for the boiler. I always use P/S piping with a Esbe thermix mixing valve on the return to always keep return temps above 140F.

Here's a pic of a two stage heating plant for a home with the mixing valves on the returns and P/S piping.

Boilerpro

Mike Kraft_2

boilerpro.............

very nice looking.How long did that one take?How many of you to rip and re-pipe?Do you have any more pics of that?Do you ever add TRV's with constant circulation to these conversions?Who's TRV's do you use?Sorry for the questions:)

cheese

Boilerpro_3

It's been a few years since that one...

> very nice looking.How long did that one take?How

> many of you to rip and re-pipe?Do you have any

> more pics of that?Do you ever add TRV's with

> constant circulation to these conversions?Who's

> TRV's do you use?Sorry for the

> questions:)

>

> cheese



so memory is a little foggy. First, it was not a gravity conversion, but a monoflow setup from the 60's with two 140,000 in boilers. It had a single National atmospheric gas boiler. I budgeted 54 man hours for that one and was pretty close. I was working by myself. The boilers are staged by a Honeywell Chronotherm 2 stage thermostat. The setup tends to provide near constant circ on typical winter days since only one boiler is usually firing, keeping the heating cyles real long. House heats much more evenly than it used to. Have more pics, but are pre digital and my scanner is RIP.

Just did my first conversion with TRV's and constant circ this past year. A large addition to a bautiful, high end farm house, along with renovation of the orignal home. The addition is all radiant in the living spaces along with the 3 car attached garage. Some radiant was added to the existing home under baths and kitchen. The original rads in the balance of the home were retrofited with Danfoss TRV's by a plumber I often work with (he refered the project to me).
A Dunkirk 140,000 in atmospheric chimney vented boiler is equipped with a reutrn mixing valve and piped P/S. The system runs full outdoor reset with a Tekmar 260 control, which also controls the pump to the Triangle Tube (tank in tank design) indirect fired water heater. I found the 260 runs really short boiler cycles on another system with this set up, so I set the diferrential to manual at 20F. I've got zone valves on the radiant zones with a single pump and another pump running constant circ for the TRV's.

Boilerpro_3

It's been a few years since that one...

so memory is a little foggy. First, it was not a gravity conversion, but a monoflow setup from the 60's with two 140,000 in boilers. It had a single National atmospheric gas boiler. I budgeted 54 man hours for that one and was pretty close. I was working by myself. The boilers are staged by a Honeywell Chronotherm 2 stage thermostat. The setup tends to provide near constant circ on typical winter days since only one boiler is usually firing, keeping the heating cyles real long. House heats much more evenly than it used to. One change I have made to my piping is that the air separator goes on the boiler loop when using trv's, not the system loop as shown in the above photo. I had a retrofit in which the air kept getting trapped in the boiler loop. I have more pics, but are pre digital and my scanner is RIP.

Just did my first conversion with TRV's and constant circ this past year. A large addition to a beautiful, high end farm house, along with renovation of the original home. The addition is all radiant in the living spaces along with the 3 car attached garage. Some radiant was added to the existing home under baths and kitchen. The original rads in the balance of the home were retrofited with Danfoss TRV's by a plumber I often work with (he refered the project to me).
A Dunkirk 140,000 in atmospheric chimney vented boiler is equipped with a reutrn mixing valve and piped P/S. The system runs full outdoor reset with a Tekmar 260 control, which also controls the pump to the Triangle Tube (tank in tank design) indirect fired water heater. I found the 260 runs really short boiler cycles (IMO) on another system with this set up, so I set the diferrential to manual at 20F. I've got zone valves on the radiant zones with a single pump and another pump running constant circ for the TRV's.

The system was running on straight outdoor reset for a couple months until stats could be installed. I designed the radiant floor to match the same design supply temps as the rads. With outdoor reset only, temps stayed with a couple degrees of the desired setpoint. It's always great when a project works as you planned!



BTW, when retrofiting TRV's, Always check which side the old rad valves are on! We've got two on the wrong side and they can make quite a racket when flow is wrong.

Live and learn.

The homeowners love the system, even though they haven't moved in yet, with the exception of the TRv's that were installed backwards. I believe the plumber got those straightened out this week.

Sorry no pics on this one, I'll have to take some the next time I'm over that way.


BP

[Deleted User]

i like that.....

looks great and looks like it was a lot of fun...i must be sick,(or lucky), to think a job like that is fun,,,some days when i'm driving in to work i feel sorry for people, cause there are actually people out there that dont like their jobs...its clear that you like yours...happy piping

Boilerpro_3

Thanks,

the lady of the house refers to them as the "Twins".

BP