Recent content by D4dog

Didnt realise this was so controversial. Balancing ensures efficiency and uniformity. Assume a 22mm supply and return, with rads coming off in 15mm, occasionally supporting up to 3 rads. You have a varispeed pump. These are desinged to maintain a constant head as rads open and close. You then...

In a mixed source heating system TRVs are useful for reducing the use of the radiators where you have eg a wood burner. In theory (but rarely in practice), if the radiators are balanced AND CORRECTLY SIZED FOR EACH ROOM, then the TRV should not really be needed...all the rads will have the same...

Working on a guess...it looks like the supply side splits just after the pump. Do you know what these split into? Upstairs and downstairs rads, or is one to hw tank and one to rads? These look like 28mm...where do they change to old cast iron?

Got to say, I agree with your engineers. Ideally, you want a 2 zone heating system (supply goes to two valves, one for upstair and one for down. You then need the upstairs return and downstairs returns to join back as close to boiler as possible), with three way control for HW, CH or both...

The HW tank coil is part of your "system", the return from that will join the ch system return at some point; this has nothing to do with the HW itself. Hw is simply gravity supply to tank.

Ok, so CH control is boiler on or off? Then the valve turns hw on or off. So you have ch or ch+HW.. You could switch to a thre port diverter...but that is pretty serious pipework from the boiler....this a very large older house I assume?

So HW is gravity fed. Cannot see why you xannot swap out the valve...I assume it is relatively easy to get to?

Looks like a one pipe system, but you dont show a vent or header tank, so assume it is closed...there should be an expansion vessel as part of the boiler or on the supply side close to the boiler. Also a pressure release valve and a pressure meter so you can check it, plus a filling loop. Your...

Thanks for all replies. Job turned into a disaster...decided to change valve in entirety, olive puller got stuck with olive on very end of pipe...which then twisted as I applied too much torque. However, i did discover after the event that you can get a replacement caleffi spindle seal (The...

Might work..there is only one vent on the heat store, and i can isolate the header tank supply to the heat store. . Had considered the insert replacement tool...excelkent idea but not at that price. Out of interest, took the trv insert apart..simple spring holding thr valve open, but no...

I have a leaking caleffi trv, around the actuator pin. I have a couple of old valves, which were not leaking, and inserts came out without any problem. I cannot source new inserts from caleffi in uk (why not is a good question) and freezing pipe is diificult. Draing gravity fed system very long...

Thanks...wasnt aware of the 3m guidance, which explains perhaps why me setup only has an isolator, not a fused one. I will advise him accordingly!

Hi all, quick question. A friend is doing up his house, and was advised by his sparky that they couldnt do any work on the electrics until a fused isolator switch was fitted between meter and CU. I suggested it simply needed to be an isolator switch, as tge fuse would serve no purpose (I have...

Thanks all for responses, although sarcasm not entirely helpful...I took guidance, whether it was out of date or not! Plan is to move the boiler onto the same phase as the remainder of the heating system, which has the added benefit of it being supported by the battery back up in the event of...

thanks all...so something like this should do the job? https://uk.rs-online.com/web/p/non-latching-relays/3863220/