Gate valves on cylinder coil

[plumb_know]

Hello everyone, I was just wondering if it is ok to put gate valves on flow and return of heating coil going into hot water cylinder. I have seen it on a couple of houses and was thinking of freezing feeds to coil and quickly putting on 2 gate valves to save draining some of heating system down. I was just wondering if there is any problem to this?

comments much appreciated

 

[happyflyer]

Why on earth would anyone want to put two valves on a cylinder heating coil unless it was leaking, usually only one valve on the return out to balance the coil since the primary coil has the lowest resistance of any part of a heating system it must have one balancing gate valve, you question is rather confusing.

Tony

System below shows the minimum amount of valves the only two valves you could add in would be either side of the 3 port valve left and right this would in fact give you two valves on the coil, you would then be able to take out the 3 port valve without draining the system, how you would physically get the valve out would be another matter, usually there isn't enough room to push the 3 pipes out of the way.

 

[secret squirrel]

I asked this question a long time ago and it was explained to me like this:

if a lot of houses are being built at the same time a lot of plumbers are told to install the pipe work, they put gate valves on because cylinders are not fitted because of the worry of theft. The system can be tested for leaks and cylinders fitted at a latter date.

 

[happyflyer]

No cannot hack that, in most cylinder cupboards the cylinder need to go in first, pipework first with or without valves you would not get the cylinder in, hell put as many valves as you want anywhere on the system it won't harm, but why would you want to freeze a coil to put a GV on it, me puzzled, me easily puzzled these days, need to go back in th'ome now, they are coming for me, see you. Take a look at this image could you get the cylinder in after the pipe???

 

[plumb_know]

I was just thinking about doing this to save draining down heating system below the coil when replacing cylinder, as in past when draining down and refilling it has dragged sludge into the system and caused problems. This way I would not need to drain f+e cistern and any pipework or rads above cylinder. I have not long qualified so still learning a lot and this idea just came to mind and wanted experienced plumbers suggestions if it was ok to do this and better ways to isolate coil when replacing cylinder. Cheers for comments

 

[secret squirrel]

No cannot hack that, in most cylinder cupboards the cylinder need to go in first, pipework first with or without valves you would not get the cylinder in, hell put as many valves as you want anywhere on the system it won't harm, but why would you want to freeze a coil to put a GV on it, me puzzled, me easily puzzled these days, need to go back in th'ome now, they are coming for me, see you. Take a look at this image could you get the cylinder in after the pipe???

You obviously haven't heard of a squirrels magical powers......

Don't worry I'll be in the straight jacket next to you...

 

[Best]

It is the proper way IMO to fit a cylinder coil with 2 gate valves. As long as they are not fitted on gravity primaries from a solid fuel boiler for example & only used on a fully pumped gas or oil system, then very handy to be able to isolate the coil if changing cylinder or if there was a blockage in coil or pipes.
Often one gate valve will be used for balancing or/and a thermostatic valve, so it may only need one extra inexpensive gate valve.

 

[lame plumber]

It is the proper way IMO to fit a cylinder coil with 2 gate valves. As long as they are not fitted on gravity primaries from a solid fuel boiler for example & only used on a fully pumped gas or oil system, then very handy to be able to isolate the coil if changing cylinder or if there was a blockage in coil or pipes.
Often one gate valve will be used for balancing or/and a thermostatic valve, so it may only need one extra inexpensive gate valve.

by the time you come to use them theyll have siezed up anyhow so why waste money on something that isnt needed?

 

[Best]

The gate valves should be in good order inside, as they are on a heating system & therefore not on ever changing water. If the spindle seizes at the packing nut, that can be freed up in seconds. If you were wanting quality, then a lever valve would be better obviously, though perhaps OTT.
I find gate valves last well on heating systems & if the customer isn't worried about a couple of pounds then the extra valve will make it an easy job to work on in the future. I see a copper cylinder just like a circulating pump or radiator - they need isolated eventually.

 

[leethegasman]

I was just thinking about doing this to save draining down heating system below the coil when replacing cylinder, as in past when draining down and refilling it has dragged sludge into the system and caused problems. This way I would not need to drain f+e cistern and any pipework or rads above cylinder. I have not long qualified so still learning a lot and this idea just came to mind and wanted experienced plumbers suggestions if it was ok to do this and better ways to isolate coil when replacing cylinder. Cheers for comments

Clean out you F E tank before you drain down to prevent dirt going in to system pipework especially if small bore.

 

[kimbo]

Cant imagine why you would need to do it the cylinder will last years and when it comes to being changed the system would probably need flushing through by then anyway.