Thanks for your reply. Your advice and an earlier thread on the subject of hoses and fittings prompted me to look at my existing plumbing in more detail.
flexible-pvc-and-smooth-fittings-avoid-at-all-costs-t38246.html?hilit=flexible%20hose%20fittings%20AGP
My pool and gear was 'inherited' from a relative. Fortunately I managed to find someone (ex pool company contractor) to install it, as none of pool stores would touch anything second-hand. Basically though, he re-used most of the original hosing and attached fittings (all clamped), replacing only the return line - and that was only because the original hose wasn't long enough to meet the new municipal regulations requiring the filter to be minimum 1.5m from the pool wall (apparently to avoid kids climbing into the pool off the filter). I wish now he'd been upfront and advised that all the plumbing really needed changing. Whilst I didn't have any leaks, when it came to disconnecting for the winter, it was apparent that some of the fittings were in a sorry state (explaining the copious silicone around the joints) as was some of the original hosing.
Whilst it is difficult to distinguish the type of hosing used solely on appearance (yes, it is that old and faded), it is just possible to make out the brand specification markings. I cant be sure about the main drain plumbing under the pool (I seem to recall solid PVC pipe when it was lying the garage), but TigerFlex F42MCR 1-1/2" hose (the normally opaque/beige ribbed hose - or is it flexi-pipe - some refer to it as 'spa hose') was used for the external part of that line to the under-skimmer 4-way valve. Don't want to touch that. I can imagine the havoc in attempting to disconnect the old and connect new hose to the buried elbow joint with pool water pouring out. Maybe a pro can do it fast.
The other lines (4-way valve to pump and pump to filter) are 1 1/2" TigerFlex CMH-41M, which I cant find listed as such, but it appears to have been originally translucent with white ribbing. The replaced return line is Eaton Arrow Flo H9 Type 9P - translucent with dark-ribbing. If I understand correctly, this type of flexible hose is intended to be used with 1 1/2" non-barbed fittings (double/reverse-clamped) , but 1-1/2" barbed (i.e. effective 1-5/8") connects with single clamps were used throughout and I can see no evidence of anything having been glued. Clearly the pro who installed it was more adept at getting 1-1/2 hose over 1 5/8" barbs. I'll maybe see how I get on with the hair-dryer/hot water trick.
I guess I could resort to using the more expensive TigerFlex F42MCR (or equivalent) throughout. I know (now) it is designed for S40 solvent-weld connections, but I don't really want to start gluing and, by all accounts, the barbed fittings/unions work OK. I don't even think the local pool store has solvent-weld versions of the quick-connect and stop-valve unions that I want to put in.
Edit: Just found a link for the Arrow-Flo hose:
http://www.jgbhose.com/Data_Returns/det ... d_id=14303
Says also to use with glue. This is confusing. Phoned a local pool store and they said, nah, clamps are OK. What type of fittings? Use smooth tail unions usually for that type of 'pool hose'. For the TigerFlex F42MCR 1-1/2" ('spa hose') use 1-1/2" (1-5/8") barbed fittings as the smooth-tail 1-1/2" fittings are too loose.
Cheers again.
Edit: Aaaaagrh.....after checking the hose I have in the store with the available fittings, turns out that both the TigerFlex CMH-41M and Arrow Flo H9 Type 9P hose are (although translucent) effectively the same as the (beige) TigerFlex F42MCR hose, in that smooth-tail fittings are too loose. Explains why all the original plumbing and changed return line were barb-clamped. The standard 1-1/2" (translucent-black ribbed) 'pool hose' (not sure of the brand), looks similar, but is much more flexible, has a narrower bore, and requires the smooth-tail fittings. Boy, you really need to be careful when choosing this stuff.
Guess I need to make a decision:
TigerFlex F42MCR 1-1/2" (or equivalent) - more expensive, less flexible - clamped/barbed fittings or glued (fittings/unions/valves?)
'Standard' 1-1/2" pool hose - cheaper, more flexible - clamped/smooth-tail fitting connections - but are they as secure ??