FAQs about fixing zone valves on hot water heating systems - set #4.
This article series explains what zone valves are, how they work, where they're installed, and how to troubleshoot and repair them.
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These hot water heating zone valve questions & answers were posted originally at ZONE VALVES, HEATING - you will enjoy reviewing the advice given there.
On 2019-11-12 by (mod) - Honeywell V8043 Zone Valve Assembly, Parts, Separatin
Neil
It sounds as if the actual valve body of your Honeywell zone valve is separating from the control head?
That's not a problem I've encountered except where someone or something was loosening the connection of control head to valve body. Vibration? Freezing?
Can you post a photo so we have a clear idea what we're discussing?
Below is an excerpt from ZONE VALVE MANUALS & WIRING
from the manual one of the Honeywell zone valve manuals at the link I gave above - the V8043
On 2019-11-12 by neil - what causes Honeywell zone valve to separate were the o ring sits
why do or what causes Honeywell zone valve to separate were the o ring sits there are four screws holding it in place and one bolt lets go pushing the o ring out are these bolt acting like a shear pin
On 2019-11-04 by (mod) -
Hank
If this problem has always been the case, since installation, then yeah I suspect the units are not wired properly; you can find some zone valve wiring examples in articles in this series;
If the problem is new I suspect shorted thermostat wires or zone control wire or a failed zone relay.
On 2019-11-04 by Hank
I have a WM boiler with 4 zone valves and W/R 1311 zone valves, they all open correctly when they call for heat but 2 do not shut off when they reach desired temperature and none of the units turn off the circulator pump. I can manually close the valves and they remain so until the next call for heat, but the circulator still does not shut off. I think it is a wiring problem from the transformer into the valves but I am not sure. Any ideas ?
On 2019-09-12 by (mod) -
Spencer
2 common causes for a zone valve refusing to open unless another zone is active are
1. Zone valve is not wired correctly
2. Zone valve is controlling a subordinate Zone that is actually fed off of one of the other zones' hot water line
It would be diagnostic to know if this problem has always existed or if it is new. If it's do then we need to ask what has changed or been modified in the system.
On 2019-09-12 1 by spencer
the zone valve for my hot water heating system does not provide heat unless one of the other four valves are on.
On 2019-06-11 by (mod) - method of putting in only one zone valve in a 3 story, 6 unit apt building
That sounds like a highly questionable idea. You can't take a generic statement like that in as soon as going to work in every building.
Furthermore in Europe where you are expert comes from that installation would be illegal. Either you're going to give each tenant control over their level of heat or you're not. And most buildings we nearest one zone and multiple apartments on multiple floors some of the people are going to always be unhappy and are going to complain of either being too hot or too cold.
There are other options discussed in this article series such as using thermostatic radiator valves that can make each radiator its own little Zone. The idea of having one zone valve doesn't seem sensible to me in the first place if there's only one zone you wouldn't need a zone valve.
On 2019-06-09 by Kay
I have been told of a method of putting in only one zone valve in a 3 story, 6 unit apt building with baseboard heaters and an oil-burning boiler. The plumber is originally from Europe and he says all I have to do is set a thermostat on the bottom of the first floor (coldest spot) and set the zone valve to the mandatory 68 degrees.
There are technically 3 zones because the heaters on each floor are all connected. But to avoid the expense of installing 3 zone valves, this guy said that if I put the thermostat on the 1st floor, when any apt calls for heat it will open and run through the baseboard heaters of all - up to 68 degrees. Then the valve shuts off and the upper apts rely on the heat rising from the lower floors. Does anyone know about this method, and does it work?
On 2019-05-21 by Anonymous
Thanks for your reply. My suspicion is that the zone valve on the hot side is stuck open.
Cool water comes in, but mixed with the hot water, it doesn't allow the circulating air to get cool. If I wanted to manually shut off the hot water, would it be done by closing the spigot on the hot line or by closing the lever valve? Or doesn't it matter?
On 2019-05-19 by (mod) -
Mike
Typically the service tech will pull the zone valve head so that we can figure out if the problem is in the actuator motor, wiring, or other head problems, or if the problem is a corroded or jammed valve itself.
With the zone valve head removed, if the zone valve stem (exposed when the control head is removed) can be rotated easily with a small pair of pliers then the issue is the control head or wiring or a zone valve controller relay.
If the zone valve will turn then you can manually rotate it to the OPEN position.
And as you'll read in this article series on heating zone valves, some models such as many of the Honeywell zone valves have a manual over-ride lever that can be latched into the OPEN position.
On 2019-05-09 by Mike
In my high-rise condo there are several 45-year-old McQuay/Daikin fan coil heat exchangers each with hot and cold water feed. One unit has stopped blowing cool air. It's unclear to me whether the hot side is stuck open or the cool side stuck closed. Each side has a Honeywell line-voltage zone valve on one side of which is a "spigot"-type water valve and on the other a lever-type valve.
We are scheduled to have these HVAC units replaced in the next few years and, based on prior repairs to other of my units, I know this repair will require cutting open my drywall and run about $800. I don't want to do that again knowing how short-term it is. I'd like some advice on how I can manually override the zone valves. I can reach down through the exhaust duct and reach everything. Thanks.
On 2019-03-25 by (mod) - type of plumbing valves for use on hot water heating zones
Art:
The suitability of a ball valve for use on hot water heating systems depends on just where it's to be used.
In particular, ball valves are intended to be used in the fully-open or fully-closed position and may not perform well or may jam or develop leaks if left partly-open or partly closed for a long time.
In comparison, stop valves and gate valves work perfectly well in a partly-open or partly-closed position.
So if the valve you are installing is to serve only as a shut-off it can be a ball valve.
But if the valve you are installing is to be used to regulate hot water flow by partly-closing the valve, such as balancing flow between two zones or sub zones, then use a gate valve.
See details at PLUMBING CONTROLS & VALVES
On 2019-03-25 by Art
Are Ball valves suitable for Hot water heating systems?
On 2019-02-02 by (mod) - zone valve gears are slipping, valve doesn't open
I suspect that the actual mechanical valve is jammed and needs replacement.
On 2019-02-02 by Alex
@Alex,
Here is a picture showing the lever not pressing on the black button but the manual switch is all the way open.
On 2019-02-02 by Alex
When I turn the zone valve manually to on, should
(1) the gears slip?
(2) the lever be pressed against the black button for the end switch?
I am wondering whether I have a defective zone valve (but it is new) as the gears feel like stripped gears when I slowly push to manual open and the lever wasn’t pressing against the black button so didn’t call for the boiler.
On 2018-12-12 by (mod) - Sources of wireless heating zone valves and zone controllers
George:
Sources of wireless heating zone valves and zone controllers
Honeywell provides heating zone control systems that can work wirelessly, including controls that can work with a smartphone app as well as a wireless thermostat.
Honeywell REDLINK
Honeywell Aquatrol
Also there's
Honeywell Wireless Zoning Adapter kit - YTH5320R1025 that includes Wireless FocusPRo Non-Programmable Thermostat and Wireless Adapter,
Also see HBX Control Systems' ZON-0550 is the first Wi-Fi enabled zoning control to the hydronic industry and can be used in many different applications from radiant heating to forced air delivery systems or a combination of both applications.
The ZON-0550 module has the capability to control up to four (4) THM-0300 or THM-0500 thermostats per controller and can operate pumps, valves or motorized dampers to provide heating and/or cooling to your HVAC system.
The control can be expandable up to a maximum of 20 zones that utilize wireless pairing communication.
The zone controller provides outputs (R-W-Y-G-X) for air delivery systems to control fancoils, furnaces, and air conditioning units. The zone outputs also allow for humidity control.
HBX Control Systems Inc.
Address:4516 112 Avenue SE
Calgary, AB, Canada
T2C 2K2
Website: http://www.hbxcontrols.com
Toll Free: +1 (855) 410 2341
Fax: +1 (403) 720 0054
Email:info@hbxcontrols.com
Support:support@hbxcontrols.com
© 2018 - HBX Control Systems Inc. Privacy/Legal Feedback youtube
Also Home Automation by JUNG includes wireless zone controls of which I've read mixed reviews.
On 2018-12-06 by (mod) - I want to move a radiator
Assuming that we are talking about a hot water and not a steam system, lowering the temperature or simply turning off off the boiler or allow your system to cool.
However you will discover if you open any pipe that you'll have a flood.
In other words you need to drain the water from the system in order to cut a pipe to move a radiator. In restoring the system to service you need to bleed all of the air from that piping or the system will be air bound and you won't have heat.
You can use the search box on any of these pages to search for
Airbound heating system
Three details of how to do that.
On 2018-12-05 by TOM
I want to move a radiator tied to one of my zones. Can I just lower the temperature on thermostat for that zone and then move the pipes to the new location. By lowering the temperature, will that prevent the water from circulating.
On 2018-12-04 by George Stone
I have z-one zone valves and the weirs going to thermostat are broken, is there wireless thermostats i could install to control them?
On 2018-06-30 by (mod) - plumber says electrician wires the zone, electrician says plumber wires the zone
Judy
I prefer to stay out of what my mother called "a lot of who-struck-john" arguments where people stand in a circle and point blame on the next person to their right.
But in my OPINION, I would prefer to have a licensed electrician do electrical wiring and a plumber do plumbing.
You need to find a different electrician, one who is familiar with wiring radiant heating systems, thermostats, zones, controllers, or who will at least read the instructions in the installation and operation manual for your heating system and each of its controls - be sure that your installer left those with you - and talk to the heating company directly if needed.
On 2018-06-30 by Judy
We're building a small house with 3 zone radiant heat. The plumber said it is all ready to go except for the wiring and to call the electrician.
The electrician says they don't do that wiring anymore...the plumber should do it. Who do I believe?
On 2018-11-03 by (mod) - zone valves don't work when on backup generator
George:
When you switch power from the main electrical panel to a backup generator it's likely that not ALL of your electrical circuits are receiving power.
So you may be powering the circuit that runs your heating boiler but the zone valves or circulator pump (s) may be on a different circuit.
On 2018-11-03 by George
Valves work fine--except when I switch the ac power to a generator--then they don't wotk at all. Power form generator is perfect sine wave and at 110 volts
Help!!
On 2018-02-18 by (mod) - Honeywell v8043 zone valves stutters or gives off a "burping" sound when it closes
I suspect you need to replace the zone valve - the valve is jamming.
But first check for air in that heating zone.
See AIR-BOUND HEATING SYSTEMS - home
On 2018-02-16 by Len F
I have a 4 zone system. One of my Honeywell v8043 zone valves stutters or gives off a "burping" sound when it closes. Other than the noise the valve functions properly. Is it possible to stop this noise?
On 2018-01-02 by Mike A
yes i saw that its by itself. Any ideas on why that 1 zone shuts the others that are already on off ?
On 2018-01-02 by (mod) - zone valve for indirect fired water heater
To be clear
Some zone controllers use one specific connection point for the water heater. Do not connect a regular heating zone thermostat there.
On 2018-01-02 by Mike A
yes mine has that plus water tank has its own circulator pump when dominating stat is disconnected all others work. also the dominating zone valve is a newer honeywell others are older.
no one was using the hot water i noticed this issue at 4am today i'm puzzled not sure if the motor became stuck open preventing others to open seems odd.
Dan also hwh was on and did not prioritize over heat but once i turned on dominating stat with others on already it shut off all other demands except water demand ? puzzled..
, just tried this turned on other stats waited 30 sec then turned on dominant stat once i did that the others stopped calling for heat?
yes mine has that plus water tank has its own circulator pump when dominating stat is disconnected all others work.
also the dominating zone valve is a newer honeywell others are older. no one was using the hot water i noticed this issue at 4am today i'm puzzled not sure if the motor became stuck open preventing others to open seems odd.
On 2018-01-02 by (mod) - if you disconnect the bad or dominating thermostat at the control box
What happens if you disconnect the bad or dominating thermostat at the control box? If all of the other's work properly that I would look at the connection points in the control box.
Some control boxes have a connection for the a tankless water heater which will automatically switch off companion heating zones when there's a call for domestic hot water.
On 2018-01-02 by Mike A
sorry dan that last comment was from me.
Dan the pump works fine problem is when heat is calling from the one stat no others turn on with temps it those zones fall but the stats are calling for heat in the falling temp zones
. the control box in basement near boiler only shows the one stat calling for heat none of the others are but all stats in the rooms are calling for heat.
On 2018-01-02 by (mod) - 4 honeywell V8043E1012 zone valve dunkirk helix boiler
Mike
if your heat used to work correctly and no one has made any changes in the wiring then I have to rule out a wiring error. However that was my first guess. My second guess is a problem with a wiring connection or a bad relay that is not turning on your circulator pump.
In general, in normal wiring no thermostat should affect the operation of the other thermostats. You might if this is an old problem follow the wiring connections
On 2018-01-02 by Mike A
sorry i meant lower the stat
@Mike A, once i lower that stat a few degrees.
on my hwbb system one of the stats calling for heats is preventing others to cycle once i raise that stat a few degrees others begin to cycle is this a bad motor in the one? 4 honeywell V8043E1012 zone valve dunkirk helix boiler
On 2017-12-28 by Stevec
I have a boiler that is down and want to know if the circulation pump (multi zone) should be turned off of left on while the system is fixed (2 days)? Any harm either way?
On 2017-12-17 0 by (mod) -
Bob
A partial air blockage or a zone valve that doesn't open fully or a damaged circulator pump impeller could cause that zone to be slow to heat up.
On 2017-12-17 by (mod) -
Joy
That sounds like either there is a wiring error or perhaps the zone 1 circulator isn't running so that zone won't get heat unless both zone valves are open and zone 2 circulator is running (perhaps abetted by the pipe arrangement of your system so that circ 2 will push water through both zones)
On 2017-12-12 by Joy
I have 2 zone water baseboard heating.
Recently we found 1st floor (zone 1) can't turn on by the thermostat unless the 2nd floor (zone 2) is on
On 2017-11-09 by Bob
I have 3 zones. 2nd floor and basement heat normally but 1st floor is incredibly slow getting up to temp.
Pipes getting hot as are baseboards. Bled the system. Replaced Taco powerhead. Any ogther thoughts?
On 2017-07-15 by (mod) -
Denys,
Thank you for asking - I've done more research on dissolved oxygen issues for heating systems - please see a detailed reply to your question, now found at
DISSOLVED OXYGEN DAMAGE CONTROL
I've asked Honeywell if the company specifically recommends any particular zone valve models as resistant to dissolved oxygen as I haven't found such products.
Meanwhile at the article I cite you'll see how industry experts suggest avoiding damage from dissolved oxgyen in residential boilers.
On 2017-07-15 by (mod) -
Re-posting a question I accidentally deleted
Question: are there zone valves that resist damage from dissolved oxygen in hydronic heating system boiler water
Denys Picard said:
Honeywell warns that makeup water feed to a boiler may damage the rubber plug of Zone Valves 8043 and make them fail.
Are they zone valves resistant to dissolved oxygen from makeup water feed? Thank you.
On 2017-07-15 by Anonymous
Thank you for the answer and reference research, as I am not familiar with these equipements, I tend to read all instructions carefully.
And yes, I have an open loop system that feeds on my softened and filtered well water, but my heating system is well equiped with many automated gas purging devices...
I hope it will be enough to ensure good performance for a reasonable time. I guess that all other brands also do put this caution then.
...
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ELECTRIC MOTOR DIAGNOSTIC GUIDE to test zone valve motors themselves
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