anticipator on T87F w/peerless boiler

Dick Charland

You have left out one piece of information, is the system steam or forced hot water? If steam, the thermostat controls the burner operation and the anticipator would be set to the cad cell control current spec. Experience allows me to say that you might move the anticipator to approx. 4-6 to get a little longer running cycle and avoid short cycling. If the system is forced hot water then you'd go by the spec of the relay or zone valve the thermostat is wired to. A more accurate determination can be made with the use of a microamp meter in series to more accurately determine the current. The anticipator is there to trick the thermostat to turn off the heat source and allow the residual heat in the system to bring the temperature to setpoint without overides.

Papa

anticipator on T87F w/peerless boiler

I'm wondering if anyone can tell me the appropriate anticipator setting for my system. I don't know much about heating systems...I have a honeywell T87F thermostat and a peerless ECT-03 boiler burning oil fuel.
The anticipator is currently set to 0.25.
The boiler has a honeywell "intermittent ignition oil primary" that indicates "thermostat load = 24VAC 0.2 AMP".
Should the thermostat anticipator setting match this (i.e 0.2 )? If not what should the setting be?
I moved into this house in the last year and there were various problems with the boiler and electrical, which is why I want to check into this. Thanks in advance.

Fred Harwood_2

Anticipation

You also can experiment with anticipation. In a well-vented steam system, try to get two cycles (on to on again) per hour. Let it run for a representative day before nudging the anticipator either way.
I just love that T87 for steam heating. If you have problems getting heat everywhere at two cycles an hour, you need better venting.

Papa

Thanks for the information. It is a steam system. I did some more reading and have increased it from .25 to .4. I'll see how this works for a couple of days. Before it would shutdown before any of the radiators had heated up.

I also read on the honeywell web site that they suggest using the highest setting for a steam system, but it is only a general recommendation.

I just want to make sure I don't damage the thermostat while making the adjustments.

scrook_2

Going up won't hurt the T-stat, but she'll run a bit longer. Also, how are your main vents?

scrook_2

Going up won't hurt the T-stat, she'll just run a bit longer. Also, how are your main vents?

Papa

Thats good to hear.

My main vents are not in good shape at this time. One pipe does not have any main vent, or anywhere to add one. I'll need to drill/tap a new hole to add one at the end of the main. I've contacted Gorton Valves and they have recommended adding two #1 vents placed at least 2 inches from the end of the main.

The other two pipes have vents at the end of the dry returns, but the previous home owner was just using regular radiator vents, one of which was completely blocked. I just ordered new vents to replace these.

Fred Harwood_2

Vents

If you have a two-pipe steam system, the main vents are only at the ends of the dry returns. If you use any, use big ones.

Proper venting of the mains via the dry returns is key to balancing your system, which then lets you tune your anticipation to two cycles per hour. Some variation may be necessary, but venting is key.

Papa

Actually I have 1 pipe steam. So is it OK to have the vents at the ends of the dry returns or should I remove these, plug the holes, and put new vents near the end of the mains?

Thanks.

Fred Harwood_2

One-Pipe Steam

Main vents on one-pipe steam usually are just after the last riser; no need to heat the dry return. If the dry return is insulated, the vent can be near its end, before the drip. The difference between venting after the last riser or at the end of an insulated dry return would be small. Again, vent well in either instance; quickly filling the main with steam evens distribution to the rads, which individually may be more readily controlled with a variable vent.

Is the dry return insulated?

Papa

Yes, everything is insulated, except the joints/elbows. Thanks for that information.