Should opening a zone valve manually normally start the boiler and pump?

[DavidSWP]

Hi,

Should opening a zone valve manually normally start the boiler and pump or just open the valve so water can pass?

 

[Dan Robinson]

Depends on the valve.

Honeywell no.

Sunvic yes.

Danfoss - I think so but can't remember.

 

[DavidSWP]

Depends on the valve.

Honeywell no.

Sunvic yes.

Danfoss - I think so but can't remember.

Ok, that explains it thanks m8. I thought it was a physical relay so thought it would connect the pump and boiler circuit. But its a Honeywell.

 

[FiremanT]

OP: Why did you want to? Has a motor failed?

 

[DavidSWP]

OP: Why did you want to? Has a motor failed?

Don't think so (well maybe pump motor). The system 3A fuse if blowing soon after there is any demand and I'm not getting enough time to see what's happening in the cabinet with the pump and the valves so I was hoping to manually operate one of the valves to see what happens with the pump. I used a helper in the end turning on the demand while I watched what happened. Valve seemed to work fine and the pump had power but wasn't moving and previously I noticed it was getting red hot so going to get the pump replaced . Suppose I could have used the programmer instead of a helper too

Pretty weird that the Honeywells don't activate the relay circuit, I thought it was a physical connection made when the valve was open so expected the relay circuit to kick in.

 

[Dan Robinson]

The valve motor opens the water way and in turn moves and arm across. When it reaches a certain point the arm pushes the microswitch. However the hook on the outer case is way before the switch point.

You can push the manual lever over harder and it will hit the switch, but only for a split second. Usually not long enough to do anything.

 

[DavidSWP]

The valve motor opens the water way and in turn moves and arm across. When it reaches a certain point the arm pushes the microswitch. However the hook on the outer case is way before the switch point.

You can push the manual lever over harder and it will hit the switch, but only for a split second. Usually not long enough to do anything.

Makes perfect sense, thanks for the explanation. I can't decide if what the Honeywell does is good or bad but it was certainly bad for my diagnostic efforts in this case.

 

[Dan Robinson]

If you want to check the controls downstream of the valve, take the lid off and use an insulated screw driver to push the switch in.

Or of course use a multi meter to test.

Remember these are not meant as consumer serviceable items. The makers assume the diagnoser will follow the industry norm procedures.

 

[Agile]

The valves are designed so that the latching lever will open the valve but not to go as far as operating the switch. Sometimes they will be able to operate the switch when they are worn but that's not intentional.

Also the latch is only to latch when the valve motor is not powered.

If the motor opens a latched valve then when the motor is depowered the lever will be taken out of the latched position and return to the normal position.