Unexpected perc to running system in vacuum on 3cph

Fizz

Noticed cellar is toasty-warm since changing t-stat setting to 3cph.

Fred

If it's not a finished space and used accordingly, I'm not sure that is a Perk. Are the steam pipes insulated well?

Fizz

Fairly well except for boiler risers and header.

Fred

I would insulate the risers and header as well. Make sure the boiler isn't running so frequently and for such short periods, at 3CPH, that it is primarily keeping the mains hot for minimal added comfort in the living portions of the house. Of course comfort is a matter of personal preference but I would try 2CPH and see how that works for you.

Fizz

Good advice, however only have 3 settings and 2 cph is not one.

PMJ

As far as comfort is concerned cold floors are generally not desirable. And hot mains mostly just warm the floor above. Drafty cold areas below are pretty much just a bad idea if you care about comfort in the first floor. Insulated mains and returns are a must and when properly done just don't lose much.

I keep my mains hot with 3cph and I think it evens things out a lot. With 2 pipe (which I think Fizz has) and natural vacuum there is basically no preheat time at all and steam from the mains continues to flow to the rads with the burner off. I have found only benefits to more cycles and see no negatives.

Fizz

Yes I do have 2 pipe(Richardson System) in vacuum. It hasn't been extremely cold this winter, but pipes stay hot, and on re-firing heat gets to rads in few minutes-several minutes quicker than no vacuum, also, 3cph has provided steady heat comparable to what hot water heat provides.

vaporvac

Fizz said:

Fairly well except for boiler risers and header.

I second @Fred , and suggest you insulate them soon. I did mine recently and it has completely changed how quickly my system heats and how well it distirbutes its steam. Major difference that I wasn't expecting since my mains have their original asbestos insulation intact.

My tstat only gives me 1 or 3as a hydronic choice.... no 2 CPH. I think running it 3 is probably just as efficient as 1 or even two IF one has vacuum. I hish I had two CPH as a choice because my rads stay warm for a really long time in vacuum and three might be too much. However, I suspect with 3 CPH you can probably stay sub-atmopheric on re-fire?

SWEI

vaporvac said:

My tstat only gives me 1 or 3as a hydronic choice.... no 2 CPH.

I don't understand why at least one of the major thermostat makers hasn't opened up the options there. Why not give us options for 1, 1.5, 2, and 3 CPH? Doing so would be trivial from a firmware prospective.

ChrisJ

SWEI said:

vaporvac said:

My tstat only gives me 1 or 3as a hydronic choice.... no 2 CPH.

I don't understand why at least one of the major thermostat makers hasn't opened up the options there. Why not give us options for 1, 1.5, 2, and 3 CPH? Doing so would be trivial from a firmware prospective.

VP8000 does.
Well, 1,2,3 etc

SWEI

I've seen several posts here where 1 CPH was to little and 2 CPH was too much. 1.5 CPH seemed like a good idea for those systems.

Fred

The 7000 Series has 1,2,3 and 5. I don't know if the incremental differences between each setting is smaller or not I.E. is a "2" setting closer to "1.5" ? From what I have read, at least with the Honeywell's the CPH is actually a programmed temp anticipation rather than a fixed number of cycles per hour. I think they said @ 1CPH the thermostat will allow a full 1 degree swing before the thermostat call for heat. at 2CPH is is like 3/4 of a degree and at 3 and 5 it is incrementally less for each of those settings.

vaporvac

Yes, the HW6 series only has 1 and 3,4,5,6 as choices. All of my prior programmables DID have 2 as an option. I'll have to check what Brands they were as I kept them as back-ups. I called HW and they said 2 CPH couldn't be added. I bought the least expensive programmable wi-fi and it was also on sale as they were changing the cover plate. I guess I got what I paid for, but the $$ difference was substantial. I put that money into NBPiping insulation.

When speaking to HW's tech support, they said their algorithm is based on multiple sensors for temp AND humidity and something else. They didn't mention lesser degree swings on other CPH settings, but that makes sense, @frank . Edit: @Fred MY house wouldn't lose that much heat in 20 or 30 minutes, otherwise.

ChrisJ

Who's Frank?

vaporvac

LOL! That's why I need the edit function. Maybe he'll pipe in when he get notification.

MarkS

Incidentally, newer Honeywell thermostats like the WiFi 9000 do not have an option for 2 CPH. Your options are Steam (1 cph) or Hot Water (3 cph). And according to HW tech support, there's no "super user" back door menu option to plug in a 2.

Fizz

Then insulate header and risers I shall. Thanks to all.