New Oil Furnace Controls advice needed

bobk

Greetings. I have a new Weil-Mclain WGO-3 oil furnace with a Hydrostat 3250-Plus control. The furnace is up and running fine on the 55 year old wiring to the thermostats and 3 circulators. My installer recommended a WMCR for circulator control and/or an outside sensor controller to modify boiler temp based on outside temperature. I notice that the HydroStat "economy" mode will adjust boiler temp based on the frequency of calls for heat, which I think would be the equivalent of adjusting for outside temp. Can anyone comment on the advantages of the WMCR and/or the outside temp sensor over what I have already? Thanks!

I'm attaching a couple of pics of the existing circulator switching.

icesailor

No matter what, its wired wrong.

It was wired wrong when it was wired up in the 1950's or 1960's.

Especially since you have no boiler protection. Is the installer going to come back every year to thoroughly clean that beast?

billtwocase

It only works if you maintain temp. The old boiler probably had a sidearm or tankless coil.

bobk

I'm a real novice, here, but it looks like the boiler is maintaining temp, period. The circulators run when the thermostats call for heat. I always thought there was some communication from the thermostats to the boiler control, but there isn't. So "economy mode" is impossible. Looks like the WMCR control recommended by my installer would be a good idea.
icesailor, sorry for the dumb question, but what do you mean by boiler protection?
Thanks for your comments.
Oh, yes, I do plan to call him back every year for maintenance.

billtwocase

You can set the up that way with the current switching relays. Use X-X treminals

bobk

Interesting. That would certainly be cheaper. Thanks!

billtwocase

I see 3 zones, is there one tied into the aquastat also?

bobk

no.
the boiler (and aqua stat) are new. The wiring in the photos is old.

billtwocase

is T-T jumped in the new control?

icesailor

billtwocase said:

It only works if you maintain temp. The old boiler probably had a sidearm or tankless coil.

That's true, but if you have two 006-A's and a 006B, to break the power to the 832's, the circulators stop while the burner runs. A common problem for Sparky back in the day.

With the R832, it had the two low voltage "X-X" terminals that should have gone to the first 006A and was the low voltage operator. and the other 006A became the high limit. The first 006A went into the tankless, the other (high limit) went at the top of the boiler. The other 006B stopped the circulators as boiler protection when the return water got too cold.

At least, that's how we did them until the triple acting controls came along. A no brainer for some Sparky's.

With R845's, you used the 5&6 as the low voltage switch. Dry contacts. No power.

billtwocase

I wire the 845's line voltage with 1/3/5 line, 4 to circ, 6 to z-r

bobk

You guys are over my head. Yes, T-T is jumped in the aquastat control

icesailor

billtwocase said:

I wire the 845's line voltage with 1/3/5 line, 4 to circ, 6 to z-r

Jumping #3 to #5 makes #5& #6 a live contact. Not a dry contact. On the 832, X-X was a low voltage switching contact. If you didn't power #5, #5 & #6 would be the dry contact. 845's let you go both ways. 832's didn't.

All solved by the Taco SR501. The best control ever to be put on the market.

I'll still bet it is wired improperly to make it do what was expected. It might work.

How many old oil boilers did I see with multiple zones, using 832's or 845's, with low voltage to the tankless well, that only one zone kicked the burner to high limit, and ran for years making hot water on the operating 006A control.

TNTC. (or remember all)

bobk

Just to be clear, my old system worked fine. The 3 circulators all operated when called by their respective thermostats, and the boiler kept the water hot. My big complaint was that the boiler was always hot, whether the thermostats were calling for heat or not. It kept my basement much too warm when outside temps were mild, and it always seemed like such a waste of oil. I assumed with the new boiler I would get better control, but apparently I need some more work to get that. By the way, there is no domestic hot water involved. It's heating only.

billtwocase

Ice, 4 and 6 are not live until the relay pulls in. Wiring my Dad taught me 30 some odd years ago, as he started out with sleeve/pot kero burners on up. If the unit a tankless coil, you could also use Z-C to #3 instead. Low limit breaks power to #4 the circ

icesailor

billtwocase said:

Ice, 4 and 6 are not live until the relay pulls in. Wiring my Dad taught me 30 some odd years ago, as he started out with sleeve/pot kero burners on up. If the unit a tankless coil, you could also use Z-C to #3 instead. Low limit breaks power to #4 the circ

That was a given. If you had no HW coil, it became a cold start with only one 006A for a high limit to switch the high limit safety. It looked to me with all the jumping of the low voltage that there might be the second 006A's.

Where I worked, the Sparkies hadn't a clue with what ZC and ZR did. They all ran RA117 Protectorelay's. And you know what happens to them if they get out of step.

billtwocase

He can use X-X in place of the jumped out T-T inside the Hydrostat, if all the relays are RA832's. All X-X same wire combo into the aquastat, and turn the low limit down. X-X from any relay will bring on the burner

bobk

I have one RA832 and two RA89A's. The 89's have X-X labels but no actual terminals. I guess I could wire the one RA832 X-X to T-T in the Hydrostat -- if I picked the zone intelligently.

icesailor

That works. None of us know what was there. I was going on the age. The paper covered Romex wiring. I haven't seen any of that since the mid 60's went by.

The Sparky that was around doing some of our wiring, used to complain that wiring 832's was a hoe'ers dream. He couldn't explain why.

Once I learned how they were supposed to be wired, it was easy.

billtwocase

I would say a this point to invest in a panel relay, and have an electrician wire it up. If all the relays were the same, it would work. I wouldn't try to choose 2 zones that don't need much heat in order to use what you have now.

bobk

Thanks for all the good information. I've decided to throw money at it, and have a professional fix it up for me. At least now, I understand what I'm getting.

icesailor

I wasn't saying that it was wrong for the reasons you might think.

Whatever is there, if it is an oil boiler without a Tankless Coil for hot water, it is PROBABLY wired wrong. If there is no coil, and those relays just run circulators, unless the thermostat and relay starts the burner as soon as the thermostat calls, it is wrong. It doesn't mean that you need a new panel relay to correct it, just that some wires need to be moved around.

Without seeing the whole boiler and the controls, its only speculation. Just because its old, doesn't mean it is wrong.

IMO, panel controls are something designed and sold to make electrical wiring idiot proof. And unless someone can explain "ZC & ZR" to Sparky, and Sparky understands what it is intended to do, panel controllers will still be wired improperly.

If whenever you turn up a thermostat, and you hear the burner start almost immediately after, its OK. Save the money. IMO.

bobk

My goal is to get some adaptive behavior from the new boiler. Theoretically, if it's really cold outside, the boiler would keep the water hotter than if it's warm outside -- and theoretically, that would save money. You could have an outside sensor, or you could infer the outside temp from the behavior of the inside thermostats. I'm pretty sure I can't get that behavior now, since I don't have an outside sensor, and there is no communication currently between the thermostats and the boiler.
To answer your question, Ice, when a thermostat calls for heat, the circulator for that zone starts. The boiler will not fire until the water temperature hits the low limit. The only input to the Hydrostat on the boiler is water temperature. The Hydrostat has the smarts to do what I want, but it doesn't have the information it needs. This is why I'm opting for the new panel.

billtwocase

That would be the best thing to do, rather than maintaining high unneeded water temps