Will a electrically operated Solenoid do the job of a 2 port Zone Valve?

[Hobartian]

I am in the process of connecting my hydronic heating system to my hot water service as a backup means of heating water for baths etc.

I have a stainless steel plate heat exchanger installed inside the hot water cylinder which is connected to a pump to circulate water through it.

The other side of the heat exchanger will be connected to the hot water supply line from the hydronic heating system.

I wish to be able to stop and start the flow of hydronically heated water through the heat exchanger and wondered whether an electrically operated solenoid would do the job or whether I should install a two port zone valve.

I am aware that solenoids work best when there is a substantial differential in pressure between the inlet and outlet of the solenoid and for that reason may not work very effectively in a hydronic circuit.

I would be pleased to find out what would work satisfactorily.

 

[quality]

A solenoid would probably be better but water hammer would probably be an issue

 

[SimonJohns]

I vote for the solenoid

2 port will allow some flow. Solenoid will close fully

 

[Hobartian]

Thanks for your responses.

It is good news that the solenoid will work satisfactorily as I already have one and thus will not need to spend more money.

 

[Hobartian]

Because of my reservations about whether solenoid valves will work properly in a hydronic circuit I performed some rough tests.

I connected a garden hose to the inlet of a solenoid valve and applied power to the solenoid. With the water tap fully turned on the solenoid stops and starts the flow of water when power is applied to the coil. However, if the pressure of the water coming into the valve is reduced to assimilate the volume of water you would expect in a hydronic circuit the flow was not shut off when power was cut to the solenoid. The flow of water continued through the valve and showed no signs of stopping until full water pressure was restored to the inlet of the valve which caused the flow of water to immediately stop.

I would like to know more about how zone valves work. The other valve which would likely work for me is a motorised ball valve. However, whilst they are made in China , there price is still fairly high.

 

[quality]

What sort of solenoid have you got ? Direct or pilot operated ?

 

[Hobartian]

I assume my solenoid is direct acting . I have attached a picture.

 

[quality]

I would agree it direct acting. Its possible that it requires a minimum inlet pressure

 

[ecowarm]

A 2 port zone valve is designed for this task

 

[Hobartian]

Hi Ecowarm,

I read your signature. 'The trouble with doing something right the first time is that nobody appreciates how difficult it is. '

When I was working I would tell juniors I liked to take short cuts. They would respond enthusiastically. I would then ask them to guess what my short cut may be. Mostly they would respond they didn't know. I would then tell them that my short cut was to do the job the right way in the first place. Look at the time and money wasted in having to make repeated service calls or having to do the job over and over again. I am also reminded of the old saying 'The poor man always pays twice.'

So what I am saying is that doing something right the first time is actually the easy way.

 

[ecowarm]

Hi Ecowarm,

I read your signature. 'The trouble with doing something right the first time is that nobody appreciates how difficult it is. '

When I was working I would tell juniors I liked to take short cuts. They would respond enthusiastically. I would then ask them to guess what my short cut may be. Mostly they would respond they didn't know. I would then tell them that my short cut was to do the job the right way in the first place. Look at the time and money wasted in having to make repeated service calls or having to do the job over and over again. I am also reminded of the old saying 'The poor man always pays twice.'

So what I am saying is that doing something right the first time is actually the easy way.

If you're good at your job, you make it look easy. Others may think it's easy until they try.